## MCQ Questions for Class 9 Science Chapter 3 Atoms and Molecules with Answers

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## Online Education for Atoms and Molecules Class 9 MCQs Questions with Answers

Atoms And Molecules Class 9 MCQ Question 1.
The chemical symbol for nitrogen gas is
(a) Ni
(b) N2
(c) N+
(d) N

Atoms And Molecules Class 9 MCQ With Answers Question 2.
The chemical symbol for sodium is
(a) So
(b) Sd
(c) NA
(d) Na

Converting grams to moles is super easy if you use mass to moles calculator above.

Class 9 Science Chapter 3 MCQ Question 3.
Which of the following would weigh the highest?
(a) 0.2 mole of sucrose (C12H22O11)
(b) 2 moles of CO2
(c) 2 moles of CaCO3
(d) 10 moles of H2O

Answer: (c) 2 moles of CaCO3

Class 9 Atoms And Molecules MCQ Question 4.
Which of the following has maximum number of atoms?
(a) 18 g of H2O
(b) 18 g of O2
(c) 18 g of CO2
(d) 18 g of CO4

Answer: (d) 18 g of CO4

Atom And Molecules Class 9 MCQ Question 5.
Which of the following correctly represents 360 g of water?
(i) 2 moles of H2O
(ii) 20 moles of water
(iii) 6.022 × 1023 molecules of water
(iv) 1.2044 × 1025 molecules of water
(a) (i)
(b) (i) and (iv)
(c) (ii) and (iii)
(d) (ii) and (iv)

Heat & Mass Transfer MCQ with detailed explanation for interview, entrance and competitive exams.

MCQ On Atoms And Molecules Class 9 Question 6.
3.42 g of sucrose are dissolved in 18 g of water in a beaker. The number of oxygen atoms in the solution are
(a) 6.68 × 1023
(b) 6.09 × 1022
(c) 6.022 × 1023
(d) 6.022 × 102321

MCQ Of Atoms And Molecules Of Class 9 Question 7.
A change in the physical state can be brought about
(a) only when energy is given to the system
(b) only when energy is taken out from the system
(c) when energy is either given to, or taken out from the system
(d) without any energy change

Answer: (c) when energy is either given to, or taken out from the system

Class 9 Science Ch 3 MCQ Question 8.
The relative molecular mass of Na2S2O3.5H2O is
(a) 250 amu
(b) 250 g
(c) 248 amu
(d) 248 g

MCQ Atoms And Molecules Class 9 Question 9.
Which of the following has maximum number of atom?
(a) 18 g H2O
(b) 18 g of O2
(c) 18 g of CO2
(d) 18 g of CH4

Answer: (d) 18 g of CH4

Ch 3 Science Class 9 MCQ Question 10.
Percentage of calcium in calcium carbonate is
(a) 40
(b) 30
(c) 48
(d) 36

Atoms And Molecules MCQ Class 9 Question 11.
Which has maximum number of molecules?
(a) 1 g of CO2
(b) 1 g of N2
(c) 1 g of H2
(d 1 g of CH4

Answer: (c) 1 g of H2

Class 9 Chemistry Chapter 3 MCQ Question 12.
What mass of carbon dioxide (CO2) will contain 3.011 × 1023 molecules?
(a) 11.0 g
(b) 22.0 g
(c) 4.4 g
(d) 44.0 g

Class 9 Chapter 3 Science MCQ Question 13.
The value of Avogadro’s constant is:
(a) 6.0 × 1024
(b) 6.01 × 1022
(c) 6.022 × 1023
(d) 6.022 × 10-23

Class 9 Science Chapter 3 MCQ With Answers Question 14.
How many times an atom of sulphur is heavier than an atom of carbon?
(a) 32 times
(b) 12 times
(c) 8/3 times
(d) 12/32 times

Chapter 3 Science Class 9 MCQ Question 15.
The number of oxygen atoms in 4.4 g of CO2 is approx.
(a) 6 × 1022
(b) 6
(c) 12 × 1023
(d) 1.2 × 1023

Question 16.
Which of the following represents 12 u?
(a) Mass of 1 hydrogen atom
(b) Mass of C-12 atom
(c) Mass of 0-16 atom
(d) 1/12th of mass of C-12 atom.

Answer: (d) 1/12th of mass of C-12 atom.

Question 17.
Which of the following would weigh the highest?
(a) 0.2 mole of sucrose (C12H22O11)
(b) 2 moles of CO2
(c) 2 moles of CaCO3
(d) 10 moles of H2O

Answer: (c) 2 moles of CaCO3

Question 18.
The molecule having an atomicity of 4 is:
(a) Sulphate molecule
(b) Ozone molecule
(c) Phosphorus molecule
(d) Methane molecule

Fill in the blanks

1. In a chemical reaction, the sum of the masses of the reactants and products remain unchanged. This is called ……………

Answer: Law of Conservation of Mass

2. A group of atoms carrying a fixed charge on them is called …………..

3. The formula unit mass of Ca3(PO4)2 is ……………

Answer: (3 × atomic mass of calcium) + (2 × atomic mass of phosphorus) + (8 × atomic mass of oxygen) = 310

4. Formula of sodium carbonate is ………….. and that of ammonium sulphate is ……………

5. Elements are represented by symbols and molecules by …………….

6. The combining power of an element is known as its …………….

7. An atom or a group of atoms which carries positive or negative charge is called an ……………..

8. The volume occupied by one mole of a gas under standard conditions of temperature and pressure is called ……………..

9. The number of atoms present in one molecule of the substance is called its ……………

10. Atomicity of H2SO4 is …………….

Match the following columns
1.

 Column I Column II (a) 28 g of He (i) 58.54 (b) 0.5 mole of O2 (ii) 7 mol (c) Molecular mass of common salt (iii) 60 g (d) 1.5 mole of Ca (iv) 16 g

 Column I Column II (a) 28 g of He (ii) 7 mol (b) 0.5 mole of O2 (iv) 16 g (c) Molecular mass of common salt (i) 58.54 (d) 1.5 mole of Ca (iii) 60 g

2.

 Column I Column II (a) Sodium carbonate (i) NaHCO3 (b) Sodium bicarbonate (ii) Na3PO4 (c) Sodium sulphate (iii) Na2CO3 (d) Sodium phosphate (iv) Na2SO4

 Column I Column II (a) Sodium carbonate (iii) Na2CO3 (b) Sodium bicarbonate (i) NaHCO3 (c) Sodium sulphate (iv) Na2SO4 (d) Sodium phosphate (ii) Na3PO4

3.

 Column I Column II (a) Silver (i) Na (b) Sodium (ii) Ag (c) Gold (iii) K (d) Potassium (iv) Au

 Column I Column II (a) Silver (ii) Ag (b) Sodium (i) Na (c) Gold (iv) Au (d) Potassium (iii) K

Answer the questions in one word:

1. Smallest particle which cannot be divided into simpler parts.

2. Which experiment led to the discovery of the atomic nucleus?

Answer: Rutherford’s alpha particle scattering experiment

3. What is the mass of a proton and a neutron?

4. What do the species $$_{1}^{3}$$A and $$_{2}^{3}$$B represent?

5. What is the formula of hydrogen carbonate?

6. What is the chemical formula of aluminium sulphate?

7. What is the formula unit mass of CaCl2?

8. What is the mass of 5 moles H2O?

1. Complete the following crossword puzzle by using the name of the chemical elements. Use the data given in table mentioned below.

Down:
2. Gold
3. Iron
5. Phosphorus
7. Hydrogen

Across:
1. Silver
4. Copper
6. Mercury

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## Periodic Classification of Elements Class 10 MCQs Questions with Answers

Periodic Classification Of Elements Class 10 MCQ Question 1.
Which of the following statements) about the modern periodic table are incorrect?
(I) The elements in the modern periodic table are arranged on the basis of their decreasing atomic numbers.
(II) The elements in the modern periodic table are arranged on the basis of their increasing atomic masses.
(III) Isotopes are placed in adjoining group(s) in the periodic table.
(IV) The elements in the modern periodic table are arranged on the basis of their increasing atomic number.
(a) Only (I)
(b) (I), (II), and (III)
(c) (I), (II), and (IV)
(d) Only (IV)
(b) (I), (II), and (III)

Explanation: The modern periodic table is a tabular arrangement of elements in increasing order of their atomic number, which is why isotopes are placed at the same position. Hence, only (III) is correct.

Periodic Table Class 10 Icse MCQ Question 2.
Which of the following statements about the modern periodic table is correct?
(a) It has 18 horizontal rows known as periods.
(b) It has 7 vertical columns rows known as periods.
(c) It has 18 vertical columns known as groups.
(d) It has 7 horizontal rows known as groups.

MCQ On Periodic Classification Of Elements Question 3.
An element X is forming the acidic oxide. Its most probable position in the modern periodic table is:
(a) Group 1 and Period 3
(b) Group 16 and Period 3
(c) Group 17 and Period 3
(d) Group 2 and Period 3

Class 10 Science Chapter 5 MCQ Question 4.
Which of the given elements A, B, C, D and E with atomic numbers 2, 3, 7,10 and 30 respectively belong to the same period?
(a) A, B, C
(b) B, C, D
(c) A, D, E
(d) B, D, E

MCQ On Periodic Classification Of Elements Class 10 Pdf With Answers Question 5.
On the basis of the electronic configuration of x|, the group number and period of the element ‘X is:
(a) Group 15 period 2
(b) Group 13 period 2
(c) Group 9 period 5
(d) Group 13 period 5
(b) Group 13 period 2

Explanation: From X95, we can have the information as:
X — element
5 — Atomic number
9 — Mass number
The electronic configuration of X is 2, 3.

Group number is found out on the basis of valance electrons. Valence electrons are 3 so group number is 10 + 3 = 13.

The period can be found out by knowing the number of shells. Since the number of shells is 2 so it belongs to period 2.

Valence Electron Calculator – This free calculator provides you with free information about Valence Electron.

Periodic Classification Of Elements MCQ Question 6.
The elements A, B, C, D and E have atomic number 9, 11, 17, 12 and 13 respectively.
Which pair of elements belongs to the same group?
(a) A and B
(b) B and D
(c) A and C
(d) D and E

MCQ Of Periodic Classification Of Elements Question 7.
An element ‘X‘ with atomic number 11 forms a compound with element ‘V with atomic number 8. The formula of the compound formed is:
(a) XY
(b) X2Y
(c) XY2
(d) X2Y3
(b) X2Y

Element X can lose one electron and has a configuration like that of Neon.
X → X+ + e
Element Y can gain two electrons to acquire noble gas configuration like that of Neon:
Y + 2e → Y2
Or we can write

Periodic Table MCQ Questions And Answers Question 8.
The positions of four elements A, B, C, and D in the modern periodic table are shown below.

Which element is most likely to form an acidic oxide?
(a) A
(b) B
(c) C
(d) D

Chapter 5 Science Class 10 MCQ Question 9.
In Mendeleev’s periodic table, gaps were left for the elements to be discovered later. Which of the following element found a place in the periodic table later?
(a) Germanium
(b) Chlorine
(c) Oxygen
(d) Silicon

Class 10 Science Ch 5 MCQ Question 10.
Elements P, Q, R, and S have atomic numbers 11,15,17 and 18 respectively. Which of them are reactive non-metals?
(a) P and Q
(b) P and R
(c) Q and R
(d) R and S
(c) Q and R

Chapter 5 Class 10 Science MCQ Question 11.
An element which is an essential constituent of all organic compounds belongs to:
(a) Group 1
(b) Group 14
(c) Group 15
(d) Group 16

MCQs Of Periodic Classification Of Elements Question 12.
According to Mendeleev’s periodic law, the elements were arranged in the periodic table in the order of:
(a) Increasing atomic number
(b) Decreasing atomic number
(c) Increasing atomic masses
(d) Decreasing atomic masses
(c) Increasing atomic masses

Explanation: Mendeleev’s periodic law is an arrangement of elements in increasing order of their atomic masses as Mendeleev’s periodic law states that, the physical and chemical properties of elements are a periodic function of their atomic masses.

Class 10 Chapter 5 Science MCQ Question 13.
Which of the following is the outermost shell for elements of period 2?
(a) K shell
(b) L shell
(c) M shell
(d) N shell

MCQ Periodic Classification Of Elements Question 14.
Which of the following gives the correct increasing order of the atomic radii of O, F, and N?
(a) O, F, N
(b) N, F, O
(c) O, N, F
(d) F, O, N

Periodic Table Class 10 MCQ Question 15.
Arrange the following elements in the order of their decreasing metallic character Na, Si, Cl, Mg, Al:
(a) Cl > Si > Al > Mg > Na
(b) Na > Mg > Al > Si > Cl
(c) Na > Al > Mg > Cl > Si
(d) Al > Na > Si > Ca > Mg

Question 16.
Which among the following elements has the largest atomic radii?
(a) Na
(b) Mg
(c) K
(d) Ca
(c) K

Explanation: Na and Mg belong to the same period, whereas Na and K are in the same group. In a group from top to bottom, the atomic radius increases, whereas it decreases in a period from left to right. Hence, the order would be K > Na > Mg and K > Ca > Mg.

Related Theory:
Atomic radius represents the distance from the nucleus to the outer shell of an element.
The trend of the atomic radius in the periodic table:

1. decreases going from left to right of a period
2. increases going down a group.

Question 17.
The electronic configurations of three elements X, Y and Z are:
X : 2 Y: 2, 8, 7 Z : 2, 8, 2
Which of the following is correct regarding these elements?
(a) X is a metal
(b) Y is a metal
(c) Z is a non-metal
(d) Y is a non-metal and Z is a metal
(d) Y is a non-metal and Z is a metal.

Explanation: Element Y has 1 less electron to complete its octet which is a property of non-metals. On the other hand, element Z has 2 extra electrons to become stable which is a property of metals..

Question 18.
Which of the following elements would lose an electron easily?
(a) Mg
(b) Na
(c) K
(d) Ca

Question 19.
Which of the following elements does not lose an electron easily?
(a) Na
(b) F
(c) Mg
(d) Al
(b) F

Explanation: Flourine has 7 electrons in the outermost orbit. Its atom size is the smallest too. Since it is the most electronegative element, it does not lose an electron easily. Sodium has one valence electron, magnesium has 2 valence electrons, and aluminium has 3 valence electrons. All these metals lose electrons easily.

Related Theory
Metals can easily lose electrons and exhibit electropositive nature, whereas non-metals have a tendency to accept electrons and exhibit electronegative nature. Na, Al, and Mg are metals, whereas F is non-metal.

Question 20.
What type of oxide would Eka-aluminium form?
(a) EO3
(b) E3O2
(c) E2O3
(d) EO

Question 21.
The element with atomic number 14 is hard and forms acidic oxide and a covalent halide. To which of the following categories does the element belong?
(a) Metal
(b) Metalloid
(c) Non-metal
(d) Left-hand side element
(b) Metalloid

Explanation: Atomic number 14 (electronic configuration of 2,8,4) is for silicon element, which is a metalloid and exhibits properties of both metal and non-metal. It has 4 electrons in its valence shell, so it tends to form covalent acidic oxide.

Question 22.
Which one of the following depicts the correct representation of atomic radius (r) of an atom?

(a) (I) and (II)
(b) (II) and (III)
(c) (III) and (IV)
(d) (I) and (IV)
(b) (II) and (III)

Explanation: The distance between the center of the nucleus and the outermost shell is known as atomic radius.

Question 23.
Which one of the following does not increase while moving down the group of the periodic table?
(b) Metallic character
(c) Valence
(d) Number of shells in an element

Question 24.
On moving from left to right in a period in the periodic table, the size of the atom:
(a) increases
(b) decreases
(c) does not change appreciably
(d) first decreases and then increases
(b) decreases

Explanation: As we move from left to right in the period of periodic table, the number of shell remains same but atomic number increases. So, the increase in nuclear charge which tends to pull electrons closer to the nuclers and reduces the size of the atoms.

Related Theory
The size of atom of an inert gas is bigger than that of the preceding halogen atom. The greater size of the inert gas atom in a period is due to the structural stability of its outermost shell consisting of an octet of electrons.

Question 25.
Which of the following set of elements is written in order of their increasing metallic character?
(a) Be, Mg, Ca
(b) Na, Li, K
(c) Mg, Al, Si
(d) C, O, N
(a) Be, Mg, Ca.

Explanation: As we move down in a group, the metallic nature of elements increases. Be, Mg, and Ca are present in the same group (group 2 of the modern periodic table). Thus, Ca has the highest metallic character.

Question 26.
An element X makes an oxide with the formula X2O3. This element will be in the same group as:
(a) Na
(b) Mg
(c) Al
(d) Cl [Diksha]
(c) Al

Explanation: The answer is Al (aluminium). The element Al is in group II! of Mendeleev’s periodic table, in which the general formula of the oxides of elements is X2O3.

Question 27.
The two pairs of elements placed by Newlands in one slot are:
(a) Co, Ni and Ce, La
(b) Be, Mg and Co, Ni
(c) F, Cl, and Ce, La
(d) Zn, Sr, and Be, Mg

Question 28.
The order of metallic character of some elements is: N < P < As < Sb < Bi. Identify the most electronegative among these elements,
(a) N
(b) P
(c) Sb
(d) Bi
(a) N

Explanation: The less metallic an element, the more electro-negative it will be. Since electronegativity is the ability of an atom to gain electrons, whereas metallic character is related to the ability of atoms to lose electrons. As N is the least metallic of the given elements, it will be the most electronegative.

Question 29.
Four elements P, Q, R and S have number of valence electrons 2,3,5 and 7 respectively. A student noted down the Group number in Modern Periodic Table and their valency as:

Select the row containing the correct group number and valency.

Question 30.
Consider the elements Li, Be, B, C, N, O and F.
(I) The most electropositive element is F.
(II) The most electronegative element is F.
(III) The only metalloid is B.
(IV) The smallest atomic size is Li.
Read the statements given above and select the incorrect statements:
(a) Both (I) and (III)
(b) Both (I) and (IV)
(c) Both (II) and (III)
(d) Both (II) and (IV)
(b) Both (I) and (IV)

Explanation: Let us arrange the given elements according to their atomic number:
Li < Be < B < C < N < 0 < F.

All the above elements have two occupied shells and are therefore placed in the second group of the periodic table.

The most electropositive element is Li and the most electronegative element is F. This is because the tendency to lose electrons decreases as we go from left to right along a period. Also, as we go from left to right along a period, the atomic radius and hence the atomic size decreases because of the increase in effective nuclear charge experienced by the valence electrons. The only metalloid is B.

Question 31.
Out of the elements F, Cl, Br and I, which is the most electronegative element?
(a) F
(b) Cl
(c) Br
(d) I
(a) F

Explanation: The electronegativity decreases as we move down a group because the ability to gain electrons decreases down a group. This is because of the decrease in the effective nuclear charge experienced by the valence electrons since a new shell is added in each group.

Since F, Cl, Br and I have 2, 3, 4 and 5 shells respectively, F is the most electronegative of these elements.

### Assertion Reasoning questions Class 10 Science Chapter 5

For the following questions, two statements are given-one labeled Assertion (A) and the other labeled Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given below:
(a) Both (A) and (R) are true and (R) is the correct explanation of the assertion.
(b) Both (A) and (R) are true but (R) is not the correct explanation of the assertion.
(c) (A) is true but (R) is false.
(d) (A) is false but (R) is true.

Question 32.
Assertion (A): Potassium has a bigger atomic radius than lithium.
Reason (R): Atomic radius decreases along a period.

Question 33.
Assertion (A): Chemical properties of the elements belonging to the same group are the same.
Reason (R): Elements belonging to the same group possess the same number of valence electrons.
(a) Both (A) and (R) are true and (R) is the correct explanation of A.

Question 34.
Assertion (A): Nitrogen is a non-metal.
Reason (R): Nitrogen has 5 valence electrons.
(a) Both (A) and (R) are true and (R) is the correct explanation of (A)

Explanation: Non-metals are the elements that form negative ions by gaining electrons.

Electronic configuration of N = 2 5
k = 2
L = 5
It needs 3 electrons to complete its octet and achieve the same configuration as that of the inert gas neon.
N + 3e→ N3-

Question 35.
Assertion (A): Newland’s law of Octaves worked well with lighter elements only.
Reason (R): Newland assumed that only 56 elements existed in nature.

Question 36.
Assertion (A): A correct position could not be assigned to hydrogen in Mendeleev’s periodic table.
Reason (R): Mendeleev Periodic Law states that ‘the properties of elements are the periodic function of their atomic numbers.
(c) (A) is true but (R) is false

Explanation: A correct position could not be assigned to hydrogen in the periodic table. The electronic configuration of hydrogen resembles that of alkali metals. Like alkali metals, hydrogen combines with halogens, oxygen and sulfur to form compounds having similar formulae.

On the other hand, just like halogens, hydrogen also exists as diatomic molecules and it combines with metals and non-metals to form covalent compounds.

Moreover, Mendeleev’s Periodic Law states that ‘the properties of elements are the periodic function of their atomic masses’.

Question 37.
Assertion (A): The elements Sodium (Na), Magnesium (Mg), Aluminium (Al) belong to the same group in Modern Periodic Table.
Reason (R): Atoms of different elements with the same number of occupied shells are placed in the same period.

Question 38.
Assertion (A): Calcium (Atomic No. 20) is more metallic than Potassium (Atomic No. 19).
Reason (R): The tendency to lose electrons decreases as we move from left to right in a period.
(c) (A) is false but (R) is true.

Explanation: Potassium (Atomic No. 19) is more metallic than Calcium (Atomic No. 20) as the tendency to lose electrons decreases as we move from left to right in a period.

The electronic configuration of Potassium is 2, 8, 8, 1 and that of Calcium is 2, 8, 8, 2. Therefore, the effective nuclear charge acting on the valence electrons of Calcium will be more than that of Potassium.

(Competency Based Questions (CBQs))

Question 1.
Sulphur is a multivalent non-metal, abundant, tasteless and and odorless. In its native form sulphur is a yellow crystalline solid. In nature it occurs as the pure element or as sulphide and sulphate minerals.Sulphur dioxide or sulphur dioxide is the chemical compound with the

formula SO2. It is a toxic gas responsible for the smell of burnt matches. It is released naturally by volcanic activity and is produced as a by product of copper extraction and the burning of fossil fuels contaminated with sulphur compounds.
Identify the group and period of the Modern Periodic Table to which Sulphur belongs. Write any two properties exhibited by sulphur.
The atomic number of sulphur is 16. It’s electronic configuration is (2, 8, 6). It belongs to group 16 and period 3 of the Modern Periodic Table.

Two properties exhibited by sulphur are allotropy and catenation.

Question 2.
Around the year 1800, only 30 elements were known. Dobereiner in 1817 and Newlands in 1866 tried to arrange the then known elements and framed laws which were rejected by the scientists. Even after the rejection of the proposed laws, many scientists continued to search for a pattern that correlated the properties of elements with their atomic masses.

The main credit for classifying elements goes to Mendeleev for his most important contribution to the early development of a Periodic table of elements wherein he arranged the elements on the basis of their fundamental property, the atomic mass and also on the similarity of chemical properties. The formulae of their hydrides and oxides were treated as basic criteria for the classification of the elements. However, Mendeleev’s classification also had some limitations as it could not assign the position to isotopes. He also left some gaps in the periodic table.
(A) State Mendeleev’s Periodic Law.
Mendeleev’s Periodic Law: It states that the properties of elements are the periodic function of their atomic masses.

Related Theory
Mendeleev concluded that when elements are arranged in order of increasing atomic masses, similar properties of element repented after a definite gap of atomic masses. This repetition of similar properties after a definite gap of atomic masses is also called periodicity in properties.

(B) Why did Mendeleev leave some gaps in the Periodic table?

(C) If the letter ‘R‘ was used to represent any of the elements in the group, then the hydride and oxide of carbon would respectively be represented as:
(a) RH4, RO
(b) RH4, RO2
(c) RH2, RO2
(d) RH2, RO

(D) Isotopes are:
(a) Atoms of an element with similar chemical properties but different atomic masses.
(b) Atoms of different elements with similar chemical properties but different atomic masses.
(c) Atoms of an element with different chemical properties but same atomic masses.
(d) Atoms of different elements with different chemical properties but same atomic masses.
(a) Atoms of an element with similar chemical properties but different atomic masses.

Explanation: Isotopes are the atoms of some element which have same atomic number but different mass number. They have same atomic number, same number of protons, same number of electrons and, same number of valence electrons. Valence electrons are responsible for the chemical properties of an element. Since isotopes of an element have same number of valence electrons. So they will have similar chemical properties.

Related Theory
Isotopes of chlorine are Cl-35 and Cl-37:

Hence, isotopes of chlorine Cl-35 and Cl-37 will have similar chemical properties.

Question 3.
Recently, two persons died in a major ammonia gas leakage at the Indian Farmers Fertilizer Cooperative Limited (IFFCO) unit at Prayagraj. The experts point out that ammonia is stored for industrial use in liquid form under high pressure or in gaseous form at low temperature, as was the case in the IFFCO unit where the accident took place. Ammonia is critical in the manufacturing of fertilizers, and is one of the largest-volume synthetic chemicals produced in the world.

What type of bond is present ammonia molecule? Wilt a solution of ammonia be a good conductor or poor conductor of electricity?
Ammonia molecule NH3 is formed by the sharing of electrons between nitrogen and hydrogen atoms as shown below:

As electron pairs are shared between the three hydrogen atoms and the nitrogen atom, a solution of ammonia in water will be a poor conductor of electricity as there are no charged particles present in an ammonia molecule.

Question 4.
The following table shows a part of the periodic table in which the elements are arranged according to their atomic numbers. (The letters given here are not the chemical symbols of the elements):

(A) Which element has a bigger atom, a or f?
a (size decreases from left to right in a period).

(B) Which element has a higher valency, k or o?

(C) Which element is more metallic, i or k?
i (metallic character decreases from left to right in a period).

Explanation:

it has to lose only one electron to acquire metallic character whereas k has to lose 3 electrons which requires a lot of energy as compared to element so element i is more metallic.

(D) Select a letter which represents a non-metal of valency 2.

Question 5.
When Sam was walking along the street, he saw several beautiful and colourful signages. In the signage industry, neon signs are electric signs lighted by long luminous gas-discharge tubes that contain rarefied neon or other gases. They are the most common use for neon lighting, which was first demonstrated in a modern form in December 1910 by Georges Claude at the Paris Motor Show.

Where would you locate the element with electronic configuration 2, 8 in the modern periodic table?
(a) Group 8
(b) Group 2
(c) Group 18
(d) Group 10
(c) Group 18
Explanation: The element with electronic configuration 2, 8 has an octet configuration, so it must be an inert gas, i.e., neon, which is placed in group 18.

Related Theory
Group 18 in the modern periodic table has noble gases (inert gases). Helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe) and radon (Rn) are present in group 18. The members of the group have eight electrons in their outermost orbit (except helium which has two electrons). Thus, they have a stable electronic configuration. These gases are chemically un-reactive, i.e., they don’t react with other elements to form compounds.

Question 6.
Atoms of eight elements A, B, C, D, E, F, G and H have the same number of electron shells but different number of electrons in their outermost shells. It was found that elements A and G combine to form an ionic compound. This ionic compound is added in a small amount to almost all vegetables and dishes during cooking. Oxides of elements A and B are basic in nature while those of elements E and F are acidic. The oxide of element D is, however, almost neutral.
Based on the above information, answer the following questions:
(A) To which group or period of the periodic table do these elements belong?

(B) What would be the nature of compound formed by a combination of elements B and F?
The compound between B and F will be ionic in nature.

(C) Which two of these elements could definitely be metals and which would be non metals?

(D) Which one of the eight elements is most likely to be found in gaseous state at room temperature?
Element H will be found in gaseous state at room temperature as it is the 8th element of the group so it would have 8 electrons in its outermost shell which is the electronic configuration of a nobel gas.

Related Theory:
Sodium chloride is used in almost all vegetables and dishes during cooking. It means A is sodium and G is chlorine.
Metals are one present on the left hand side of modern periodic table and non-metals on the right hand side. As we know oxides of metals are basic in nature and oxides of non-metals form acidic oxide. The elements given one.

Question 7.
Analyse the following table given below and answer the questions that follow:
Given alongside is a part of the periodic table. As we move vertically downward from Li to Fr:

 Li Be Na K Rb Cs Fr Ra

(A) Which among the following has larger size of atoms?
(a) Li
(b) Na
(c) Cs
(d) Fr
(d) Fr

Explanation: Fr has greater atomic size as the atomic size increases gradually from lithium to francium.

(B) Which one of the following does not increase while moving down in group of the periodic table?
(b) Metallic character
(c) Valence
(d) Number of shells in an element

(C) Name two properties of elements whose magnitude change while going from top to bottom in a group of the periodic table. In what manner do they change?

(D) Rewrite the following statement after correction, if necessary:
“Groups have elements with consecutive atomic numbers”
Periods have elements with consecutive atomic numbers.

Question 8.
In addition to its applications in electronic devices, germanium is used as a component of alloys and in phosphors for fluorescent lamps. Because germanium is transparent to infrared radiation, it is employed in equipment used for detecting and measuring such radiation, such as windows and lenses. Silicon is used in building and construction, able to bond materials such as concrete, glass, granite, steel and plastics, enabling them to work better and last longer. Solar cells made out of silicon currently provide a combination of high effciency, low cost, and long lifetime.

Three elements B, Si and Ge are:
(a) Metals
(b) Non-metals
(c) Metalloids
(d) Metal, non-metal and metalloid respectively
(c) Metalloids

Explanation: The elements boron (B), silicon (Si) and germanium (Ge) exhibit intermediate properties of metals and non-metals, therefore, they are called as metalloids. These elements are placed in between metals and non-metals diagonally as a zigzag line to separate them.

Related Theory
A few other elements are arsenic (As), antimony (Sb), tellurium (Te), polonium (Po) and astatine (At).

Question 9.
Analyse the following table given below and answer the questions that follow:
The atomic radii of the element of the second period are given below:

(A) Arrange these elements in decreasing order of their atomic radii.
Elements in decreasing order of their atomic radii

(B) Why does atomic radius decreases as we move from left to right in a period?

(C) Which is not true about the noble gases?
(a) They are non-metallic in nature
(b) They exist in atomic form
(c) They are radioactive in nature
(d) Xenon is the most reactive among these
(c) They are radioactive in nature.
Explanation: Noble gases are inert and are not radioactive in nature.

Related Theory
Noble gases cannot lose or gain or shore electrons as their outermost shell is complete.
He has 2 electrons in its K shell, which is completely filled as K shell can accommodate maximum of 2 electrons whereas Ne has 8 electrons in its L shell and its octet is complete so they exist in atomic form.

(D) Which of the following is the outermost shell for elements of period 2?
(a) K shell
(b) L shell
(c) M shell
(d) N shell

Question 10.
A student tried to assign a correct position to hydrogen in Mendeleev’s Periodic Table by looking at its resemblance to alkali metals and the halogen family.
Another student wondered where she would place the isotopes of chlorine, Cl-35 and Cl-37 as they were atoms of the same element.

(A) No fixed position could be given to hydrogen in the Mendeleev’s Periodic Table as:
(I) Electronic configuration of hydrogen resembles that of alkali metals.
(II) Hydrogen combines with metals and non-metals to form ionic compounds.
(III) Hydrogen exists as diatomic molecules just like alkali metals.
(IV) Hydrogen combines with halogens, oxygen and sulphur to form compounds having similar formulae as alkali metals.
(a) Both (I) and (II)
(b) Both (II) and (III)
(c) Both (I) and (IV)
(d) Both (III) and (IV)
(c) Both (I) and (IV)

Explanation: As Mendeleev’s periodic table was based on atomic mass, no fixed position could be assigned to hydrogen. However, it has one valence electron just like alkali metals Li, Na, K etc. Moreover, hydrogen combines with haLogens, oxygen and sulphur just like alkali metals do. However, hydrogen combines with metals and non-metals to form covalent bonds by sharing of electrons and exists as diatomic molecules like halogens.

(B) The formula of hydrides of elements belonging to a Group of Mendeelev’s Periodic Table is RH2. The Group Number to which the element belongs is:
(a) Group IV
(b) Group V
(c) Group VI
(d) Group VII

(C) The formula of oxides and hydrides of elements belonging to different Groups of the Mendeleev’s Periodic Table is given below:

The letter ‘R’ is used to represent any of the elements in the group.
Select the row containing incorrect information.
(a) Croup No.: 1, Formula of oxides; RO, Formula of Hydrides; RH Explanation: The formula of hydrides and oxides of elements belonging to group I of Mendeleev’s table is R2O and RH respectively. For example, formula of oxide and hydride of element Li will be Li2O and LiH respectively.

(D) Select the correct statement regarding position of isotopes in Mendeleev’s Periodic Table:
(a) Mendeleev left some gaps in his periodic table for the isotopes.
(b) Isotopes were discovered after Mendeleev had proposed his periodic classification of elements.
(c) Mendeleev placed both the isotopes of chlorine (Cl-35 and Cl-37) under the same slot as they had same chemical properties.
(d) Mendeleev placed both the isotopes of chlorine (Cl-35 and Cl-37) in different slots as they had different masses.

(E) Mendeleev left some gaps in his Periodic Table as he predicted the existence of some elements that had not been discovered at that time. Which of the following elements discovered later, have properties similar to Eka-boron?
(a) Gallium
(b) Germanium
(c) Caesium
(d) Scandium

Question 11.
We all have heard about the damage being done to the Taj Mahal and our environment due to high levels of oxides of certain elements in the atmosphere. Acid rain is caused by a chemical reaction that begins when these oxides are released into the air. These substances can rise very high into the atmosphere, where they mix and react with water, oxygen, and other chemicals to form more acidic pollutants, known as acid rain.

Which of the following elements will form an acidic oxide?
(a) An element with atomic number 7
(b) An element with atomic number 3
(c) An element with atomic number 12
(d) An element with atomic number 19
(a) An element with atomic number 7

Explanation: Non-metals form acidic oxides. The element with atomic number 7 is a non-metal (nitrogen). Rest three elements with atomic numbers, 3 (Li), 12 (Mg) andl9 (K) are metals and hence, form basic oxides.

Question 12.
Atomic radii of the elements of the second period are given below:
Period II elements: B Be O N Li C
Atomic radius (pm): 88 111 66 74 152 77
Atomic radii of first group elements are given below and arrange them in an increasing order.
Group 1 Elements 6: Na Li Rb Cs K
Atomic Radius (pm): 186 152 244 262 231
(A) Select the incorrect statements:
(I) The atomic radius decreases in moving from left to right along a period.
(II) The atomic radius increases in moving from left to right along a period
(III) As we move from left to right along a period, there is an increase in nuclear charge which tends to pull the electrons closer to the nucleus.
(IV) As we move from left to right along a period, there is a decrease in nuclear charge which tends to pull the electrons away from the nucleus.
(a) Both (I) and (III)
(b) Both (II) and (III)
(c) Both (I) and (IV)
(d) Both (II) and (IV)
(d) Both (II) and (IV)

Explanation: As we move from left to right along a period we see that the atomic radius decreases. This is due to an increase in nuclear charge which tends to pull the electrons closer to the nucleus and reduces the size of the atom.

(B) Two students recorded their observations on variation of atomic radii of first group elements as given below:

 First Student Second Student (a) Li has the smallest atomic radii Na has the smallest atomic radii (b) Atomic radius of Rb > Cs Atomic radius of Cs > Rb (c) Cs has the biggest atomic radius Li has the smallest atomic radius (d) Atomic radius of K > Na The atomic radius of Na > K

Select the row containing the correct observation by both students.
(c) First student: Cs has the biggest atomic radius, Second student: Li has the smallest atomic radius.

Explanation: The atomic radius and hence the atomic size increases as we move down a group. This is because a new shell is added as we move down the group. This increases the distance between the nucleus and the valence shell.

As Cs lies at the bottom of group 1, and Li lies at the top, Cs has the biggest atomic radius among Group 1 elements.

(C) The atomic size of Na is greater than Li because:
(a) Na has three shells, whereas Li has two shells in its atom
(b) The atomic number of Na is greater than Li
(c) As we go down a group, distance between outermost electrons and nucleus decreases.
(d) The mass of Na atom is greater than Li atom

(D) The graph of variation of atomic radius with atomic number for alkali metals and halogens is shown below:

Select the correct observation:
(a) Na has a bigger atomic radius than Li due to decrease in nuclear charge
(b) F has a smaller atomic radius than Li due to increase in nuclear charge
(c) Na and Cl belong to the third period of Modern Periodic Table and have identical electronic configuration.
(d) Elements of Group 17 have the biggest atomic size in their respective periods.
(b) F has a smaller atomic radius than Li due to increase in nuclear charge

Explanation: Both F and Li lie in the second period as they have two occupied shells. However, as the effective nuclear charge is more in the case of F as compared to Li, F has a smaller atomic radius than Li.

The atomic radius decreases in moving from left to right along a period and it increases in going from top to bottom along a group.

(E) The correct increasing order of the atomic radii of the elements Mg, Si and Cl is:
(a) Mg > Si > Cl
(b) Si < Cl < Mg
(c) Cl < Si < Mg
(d) Cl < Mg < Si

Question 13.
Chemists have always looked for ways of arranging the elements to reflect the similarities between their properties. The earliest attempt to classify the elements was in 1789, when Antoine Lavoisier grouped the elements based on their properties into gases, non-metals, metals and earths. Several other attempts were made to group elements together over the coming decades. In 1829, Johann Dobereiner recognised triads of elements with chemically similar properties, such as lithium, sodium and potassium, and showed that the properties of the middle element could be predicted from the properties of the other two. It was not until a more accurate list of the atomic mass of the elements became available at a conference in Karlsruhe, Germany in 1860 that real progress was made towards the discovery of the modern periodic table.
(A) Which of the following elements form Dobereiner’s triads?
(a) Li, Na, K
(b) Ca, Sr, Ba
(c) F, Cl, Br
(d) Cl, Br, I

(B) Given below are four statements on Dobereiner’s triads:
(I) One triad identified by Dobereiner was (Ca, Na, Ba)
(III) The atomic mass of the middle element was roughly equal to the atomic masses of the other two elements.
(IV) Dobereiner could identify only three triads from the elements known at that time.
Identify the incorrect statements.
(a) Both (I) and (III)
(b) Both (II) and (III)
(c) Both (I) and (IV)
(d) Both (II) and (IV)
(a) Both (I) and (III)

Explanation: Dobereiner’s triods consisted of three elements having simiLar properties. He coutd identifij onLy three triads out of the elements discovered at that time. They were (Li, Na, K), (Ca. Sr. Ba) and (Cl, Br, I). The atomic mass of the middle element was roughly equal to the average of the atomic masses of the other two elements.

(C) A & B are two elements having similar properties which obey the law of octaves. How many elements are there in between A and B?
(a) 5
(b) 6
(c) 7
(d) 8

(D) Which of the following is not a limitation of Newland’s law of octaves:
(a) The elements fluorine, chlorine and bromine are placed in the same column (musical note).
(b) Newlands’ Law of Octaves worked well with lighter elements only.
(c) Newlands assumed that only 56 elements existed in nature and no more elements would be discovered in the future.
(d) In order to fit elements into his Table, Newlands adjusted cobalt and nickel in the same slot.
(a) The elements fluorine, chlorine and bromine are placed in the same column (musical note).

Explanation: The elements fluorine, chlorine and bromine are placed in the some column (musicol note) as they have similar properties and are known as halogens. Even in the modern periodic table, they are placed in the same group, group 17.

(E)Given below are few observations on properties of eLements.

Select the option containing the correct observation.
(d) Observation: Properties of Li and Na were found to be similar, Doberimer’s Triods: Yes, NewLands’ Law Yes.

Explanation: Both Be and Mg were placed under the same note in Newland’s law, but were not part of Döbereiner’s triads. Dobereiners Triads

Question 14.
Valency of an element is the combining capacity of an atom of the element. The volency of an element is related to how many electrons are in the outer shell. The chemical formula for a substance shows how many atoms of each element are present in a molecule, or the proportion of atoms of each element. The formula can be worked out using the volency.

The molecular formula of a compound can be predicted knowing the valency of the constituting atoms. Knowledge of valency is useful in calculating equivalent weight of elements, writing down chemical equations and in checking the structures of molecules. Some elements show variable valency and the valency determines the properties of elements. The table below gives atomic number of five elements written as P, Q, R, S and T, which are not their real chemical symbols.

 Element Atomic Number P 4 Q 9 R 14 S 18 T 20

(A) The valency and group number in Modern Periodic Table of four elements are given below:

Select the option containing the correct valency and group number.

(B) The electronic configuration of the element T is:

(C) The valency of eLements:
(a) Decreases as we go down a group
(b) Remons same in a group
(c) Increases as we go down a group
(d) First increases and then decreases as we go down a group
(b) Remains same in a group

Explanation: The valency of elements is equal to the number of valence electrons in case of metals and (8 – valence electrons) for non-metals. Moreover, all elements belonging to the same group have same outer shell electronic configuration. Therefore, valency of elements remains same in a group.

(D) As per the table given above, the element(s) which wilL form only covaLent bonds ¡s:
(I) P
(II) R
(III) S
(IV) Q
(a) Only (I)
(b) Only (II)
(c) Both (I) and (IV)
(d) Both (II) and (III)

(E) Select the incorrect statement:
(a) Valency of elements of second period is 2.
(b) Valency of an element is determined by the number of valence electrons present in the outermost shell of its atom.
(c) Valency of metals is equal to the number of valence electrons.
(d) Valency of elements of Group 18 of Modern Periodic Table is 0.

Question 15.
The elements can be classified as metals, nonmetals, or metalloids. In the Modern Periodic Table, a zig-zag line separates metals from non-metals.

The metals are to the Left of the line (except for hydrogen, which is a nonmetaL), the nonmetals are to the right of the Line, and the elements immediately adjacent to the line are the metalioids.
Ionization energy is the minimum amount of energy required to remove the most loosely bound electron of an isolated neutral gaseous atom or molecule. It is expressed as
X(g) + energy → X+(g) + e

where X is any atom or molecule, X+ is the ion with one electron removed, and e- is the removed electron.
Since the metals are further to the left on the periodic table, they have low ionization energies.
(A) Which of the following elements is not a metalloid?
(a) Si
(b) Ge
(c) As
(d) Ar
(d)Ar

Explanation: The metalloids are B, Si. Ge, As, Te and Po. Ar (Argon) is a noble gas having atomic number 18.

(B) An element A (atomic number 17) reacts with an element B (atomic number 14) to form a tetravalent halide.
Select the option which gives the correct nature of elements A and B:

 Element A Element B (a) Metal Non-metal (b) Non-metal Non-metal (c) Non-metal Metalloid (d) Metalloid Metalloid

(C) Four statements are given below.
(I) The metalloids are placed in Groups 13 – 16 in the Modern Periodic Table
(II) Boron is the only metalloid in group 13 of the Modern Periodic Table.
(III) Group 14 of the Modern Periodic Table contains only metalloids.
(IV) Group 17 of the Modern Periodic Table contains both metalloids and non-metals
Select the correct statement(s):
(a) Both (I) and (II)
(b) Both (I) and (III)
(c) Both (II) and (IV)
(d) (I), (II) and (IV)

(D) Variation of the ionization energy of elements with atomic number upto atomic number 20 is given below:
From the graph we can conclude that the tendency to lose electrons:
(a) Increases as we go down the group
(b) Decreases as we go down the group
(c) Remains constant in a group
(d) No definite conclusion can be made

(E) The metalloid which is the second most abundant element on earth’s crust after oxygen and is widely used in electronics is:
(a) B (b) Ge
(c) Si (d) As

Question 1.
State the common characteristic of the following elements: Boron, Silicon, Germanium and Arsenic

Question 2.
State the Periodic Law on which the Modern Periodic Table is based.
Periodic Law on which the Modern Periodic Table is based is termed as Modern Periodic Law. According to Modern Periodic Law – The properties of elements are a periodic function of their atomic numbers.

Related Theory
Modern Periodic Table or Long form of Periodic table was prepared by Henry Moseley and is based on electronic configuration of elements. The elements are arranged in increasing order of their atomic numbers. Modern Periodic Table consists of 18 vertical columns called 7 horizontal rows called periods.

Question 3.
How many metals are present in second period of periodic table?

Question 4.
The atomic radii of three elements A, B and C of a periodic table are 186 pm, 104 pm and 143 pm respectively. Giving a reason, arrange these elements in the increasing order of atomic numbers in the period.
Since atomic size decreases along a period and the atomic number increases. So, the element with smaller radii, has the highest atomic number.

Hence, B has the highest atomic number followed by C and A i.e. A < C < B

Explanation: The atomic size is the distance between the centre of the nucleus and the outermost shell of an isolated atom. The atomic radius is measured in picometre, (1 pm = 10-12 m).

The atomic radius decreases in moving from left to right along a period. This is due to:
As the atomic number increases, the nuclear charge increases. Increase in nuclear charge tends to pull the electrons closer to the nucleur and reduce the size of the atom.

Question 5.
Consider the following :
20Ca, 8O,16S, 4Be
Which of the above elements would you expect to. be in group 2 of the Modern Periodic table?
Consider the electronic configuration of elements:
Ca: 2, 8, 8, 2 O: 2, 6 S: 2, 8, 6 Be: 2, 2
As Ca and Be all have the same number of valence electrons (2), they belong to group 2 of the Modern Periodic Table.

Question 6.
Define electropositivity.
Electropositivity is the ability metals to lose electron to form positive ions.
Explanation: Metals have 1, 2, 3 valence electrons and have a strong tendency to lose these to form positive ions, so metal are called electropositive elements.
For example:

as we move down in a group in the periodic table, atomic size increases. As a result, force of attraction between the nucleus and valence electrons decreases.

Question 7.
Write two reasons responsible for the late discovery of noble gases
The two reasons for the late discovery of noble gases are:

1. Their low concentration in the atmosphere.
2. Their chemical inertness or very less reactivity.

Question 8.
What were the criteria used by Mendeleev in creating has periodic table
The criteria used by Mendeleev in creating his periodic table were the relationship between the atomic masses of the elements and their physical and chemical properties and formulae of the hydrides and oxides formed by an element.

## MCQ Questions for Class 10 Science Chapter 1 Chemical Reactions and Equations with Answers

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## Online Education for Chemical Reactions and Equations Class 10 MCQs Questions with Answers

Chemical Reaction And Equation Class 10 MCQ Question 1.
Which of the following is not a physical change?
(a) Boiling of water to give water vapour.
(b) Melting of ice to give water.
(c) Dissolution of salt in water.
(d) Combustion of Liquefied Petroleum Gas (LPG).
(d) Combustion of Liquefied Petroleum Gas (LPG).

Explanation: Since the combustion of Liquefied Petroleum Gas (LPG) produces new substances, a lot of heat is produced along with carbon dioxide and water vapour. It is also irreversible in nature. So it is a chemical change.

However, boiling of water to give water vapour, melting of ice to give water and dissolution of salt in water are physical changes, as here no new substance is formed, only the physical state of the substance changes.

A physical change does not produce a new substance although the initial and final substances appear different and it is reversible.

During a chemical change, the chemical composition of the substance changes and new substances with new properties are formed. Energy is either released or absorbed during a chemical change and it is irreversible.

Top free images & vectors for Compound chemical formula calculator in png, vector, file, black and white, logo, clipart, cartoon and transparent.

Chemical Reactions And Equations Class 10 MCQ Question 2.
Which of the following is (are) an endothermic process(es)?
(I) Dilution of sulphuric acid
(II) Sublimation of dry ice
(III) Condensation of water vapours
(IV) Evaporation of water
(a) (I) and (III)
(b) Only (II)
(c) Only (III)
(d) (II) and (IV)

Class 10 Science Chapter 1 MCQ Question 3.
Strong heating of ferrous sulphate leads to the formation of a brown solid and two gases. This reaction can be categorised as:
(a) displacement and redox.
(b) decomposition and redox.
(c) displacement and endothermic.
(d) decomposition and exothermic.
(b) decomposition and redox reaction.

Explanation: When FeSO4 is heated strong, it decomposes to form a brown solid ferric oxide, sulphur dioxide and sulphur trioxide.

In this reaction, FeSO4 decomposes and forms new products so it is a decomposition reaction. Here FeSO4 is oxidised to Fe2O3 by loss of electrons. So this part of the reaction is oxidation reaction FeSO4 is also reduced to SO2 and SO3 by a gain of electrons.

Hence, the Heating of FeSO4 is both decomposition and Redox reaction.

Related Theory:
A reaction is called redox when both oxidation and reduction are taking place simultaneously.
The oxidation process involves:

1. Gain of oxygen
2. Loss of hydrogen
3. Loss of electrons

Reduction process involves:

1. Loss of oxygen,
2. Gain of hydrogen
3. Gain of electrons

The substance which loses electrons i.e. gets oxidised, acts as a reducing agent and the substance which gains electrons, i.e. it gets reduced and acts as an oxidising agent.

Class 10 Chemical Reactions And Equations MCQ Question 4.
Which among the following is (are) double displacement reaction(s)?
(I) Pb + CuCl2 → PbCl2 + Cu
(II) Na2SO4 + BaCl2 → BaSO4 + 2NaCl
(III) C + O2 → CO2
(IV) CH4 + 2O2 → CO2 + 2H2O
(a) (I) and (IV)
(b) Only (II)
(c) (I) and (II)
(d) (III) and (IV)
(b) only (II)
Explanation: A double displacement reaction involves the displacement of two ions of two different compounds that results in the formation of new compounds. Here, only in reaction (II), ions of both reactants are exchanged and two entirely different compounds are formed. For example.
Na2SO4 + BaCl2 → BaSO4(s) (White ppt) + 2NaCl(aq)

In a double displacement reaction, exchange of ions takes place i.e., SO42- exchange place with Cl ion. It is also called a precipitation reaction as BaSO4 is precipitated as insoluble salt in the solution.

Ch 1 Science Class 10 MCQ Question 5.
Barium chloride on reacting with ammonium sulphate forms barium sulphate and ammonium chloride. Which of the following correctly represents the type of reaction involved?
(I) Displacement reaction
(II) Precipitation reaction
(III) Combination reaction
(IV) Double displacement reaction
(a) Only (I)
(b) Only (II)
(c) Only (IV)
(d) (II) and (IV)

Class 10 Chemistry Chapter 1 MCQ Question 6.
When copper turnings are added to silver nitrate solution, a blue coloured solution is formed after some time. It is because copper:
(I) Displaces silver from the solution
(II) forms a blue coloured complex with AgNO3
(III) Is oxidized to Cu2+
(IV) ls reduced to Cu2+
(a) (I) and (II)
(b) (II) and (III)
(c) (I) and (III)
(d) (II) and (IV)
(c) (I) and (III)
Explanation: Copper is placed above silver in electrochemical series and thus reaction occurs
Cu + 2Ag+ → Cu2+ + 2Ag

Chemical Reaction And Equation MCQ Question 7.
One of the following does not happen during a chemical reaction. This is:
(a) Breaking of old bonds and formation of new bonds
(b) Formation of new substances with entirely different properties
(c) Atoms of one element change into those of another element to form new products
(d) A rearrangement of atoms takes place to form new products
(c) atoms of one element change into those of another element to form new products. Explanation: It is not atoms but the bonds between these atoms break and form during chemical reactions. Atoms of elements can rearrange but cannot change into other elements.

Chemical Reactions And Equations MCQ Question 8.
You are given the solution of lead nitrate. In order to obtain a yellow precipitate, you should mix with it a solution of:
(a) potassium chloride
(b) potassium nitride
(c) potassium sulphide
(d) potassium iodide
(d) potassium iodide
Explanation: Potassium iodide on reacting with lead nitrate gives yellow precipitate of Lead iodide.
2KI + Pb(NO3)2 → Pbl2 + 2KNO3

MCQ On Chemical Reactions And Equations Question 9.
In which of the following chemical equations do the abbreviations represent the correct states of the reactants and products involved at reaction temperature?
(a) 2H2(l) + O2(l) → 2H2O(g)
(b) 2H2(g) + O2(l) → 2H2O(g)
(c) 2H2(g) + O2(g) → 2H2O(l)
(d) 2H2(g) + O2(g) → 2H2O(g)

Chapter 1 Science Class 10 MCQ Question 10.
Dilute hydrochloric acid is added to granulated zinc taken in a test tube. The following observations are recorded. Point out the correct observation:
(a) The surface of metal becomes shiny.
(b) The reaction mixture turns milky.
(c) Odour of a pungent-smelling gas is recorded.
(d) A colourless and odourless gas is evolved. [Diksha]
(d) A colourless and odourless gas is evolved. Explanation: The chemical reaction between dilute hydrochloric acid and granulated zinc is represented as follows:
Zn + 2HCl → ZnCl2 + H2
The product, zinc chloride, does not turn the reaction milky. Hydrogen gas evolved is colourless and odourless and released by the formation of bubbles. Hence, option (d) is correct.

MCQ Of Chemical Reaction And Equation Question 11.
On heating, a blue coloured powder of copper (II) nitrate in a boiling tube, a black substance X, oxygen gas and a brown gas Y was formed. Select the option which identifies the products correctly:

(c) X is Copper Oxide and Y is Nitrogen Dioxide Explanation: When blue coloured powder of copper (II) nitrate is heated, it decomposes to form black coloured substance which is copper oxide, oxygen gas and brown gas nitrogen dioxide.

The chemical equation for the reaction taking place is:

Class 10 Science Ch 1 MCQ Question 12.
In the equation:
Cu + XHNO3 → CU(NO3)2 + yNO2 + 2H2O
The values of x and y are:
(a) 3 and 5
(b) 8 and 6
(c) 4 and 2
(c) 7 and 1
(c) Cu + 4HNO3 → Cu(NO3)2 + 2NO2 + 2H2O
Explanation: In order to find the values of x and y, we need to balance the chemical equation by equating the number of atoms of each element on both sides in the given equation.
Cu + XHNO3 → CU(NO3)2 + yNO2 + 2H2O

Equating the number of H atoms on both sides as per the law of conservation of mass, x = 4.
Putting this value in either the no. of atoms of N or O,
x = y + 2 means y = x – 2 = 4 – 2 = 2.
Therefore, x = 4 & y = 2 is the correct answer

Chemical equation balance the equation calculator finds the stoichiometric coefficients to balance chemical equations incl.

MCQ Questions For Class 10 Science Chapter 1 Question 13.
In which of the following chemical equations, the abbreviations represent the correct states of the reactants and products involved at reaction temperature?
(a) AlCl3(aq) + 3NH4OH(aq) → Al(OH)3(s) + 3NH4Cl(aq)
(b) AlCl3(aq) + 3NH4OH(l) → Al(OH)3(aq) + 3NH4Cl(s)
(c) AlCl3(aq) + 3NH4OH(aq) → Al(OH)3(s) + 3NH4Cl(aq)
(d) AlCl3(aq) + 3NH4OH(aq) → Al(OH)3(aq) + 3NH4Cl(s)
(a) AlCl3(aq) + 3NH4OH(aq) → Al(OH)3(s) + 3NH4CL(aq)

Explanation: When ammonium hydroxide solution is added to aluminium chloride solution, a white precipitate of aluminium hydroxide is formed alongwith ammonium chloride solution.

Chemical Equations And Reactions Class 10 MCQ Question 14.
The reaction 2HNO3 + Ca(OH)2 → Ca(NO3)2 + 2H2O is an example of:
(I) displacement reaction.
(II) double displacement reaction.
(III) neutralisation reaction.
(IV) combination reaction.
(a) (I) and (II)
(b) (II) and (III)
(c) (III) and (IV)
(d) (I) and (IV)

Chemical Equation And Reaction Class 10 MCQ Question 15.
Consider the following chemical equation:
X(aq) + sodium chloride(aq) → Y(white ppt) + Sodium nitrate(aq)

### Assertion Reasoning questions Class 10 Science Chapter 1

For the following questions, two statements are given: one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given below:
(a) Both (A) and (R) are true and (R) is the correct explanation of the assertion.
(b) Both (A) and (R) are true, but (R) is not the correct explanation of the assertion.
(c) (A) is true, but (R) is false.
(d) (A) is false, but (R) is true.

Question 16.
Assertion (A): Following is a balanced chemical equation for the action of steam on iron:
4Fe + 4H2O(g) → Fe3O4 + 4H2
Reason (R): The law of conservation of mass holds good for a chemical equation.
(b) Both (A) and (R) are true but (R) is not the correct explanation of (A).

Explanation: Iron (Fe) metal does not react with cold or hot water but it reacts with steam to form a metal oxide and hydrogen.

The law of conservation of mass holds good for a chemical reaction. The statement is true but it does not explain the equation given in the Assertion.

Question 17.
Assertion (A): Magnesium ribbon burns with a dazzling white flame.
Reason (R): Magnesium ribbon undergoes physical change on burning and melts.

Question 18.
Assertion (A): While equalizing the number of atoms to balance a chemical equation, we alter the formula of the compounds or elements involved in the reaction.
Reason (R): Chemical equation is balanced by making the number of atoms of each element equal on both sides of the arrow.
(d) (A) is false, but (R) is true.
Explanation: A chemical equation is balanced by making the number of atoms of each element equal on both sides of the arrow without altering the formula of the compounds or elements involved in the reaction. It is balanced by putting coefficients in front of the compounds or elements.

Question 19.
Assertion (A): The reaction of calcium oxide with water to produce slaked lime releasing a large amount of heat is a combination reaction.
Reason (R): Double displacement reactions are the reactions in which there is an exchange of ions between the reactants.
(b) Both (A) and (R) are true but (R) is not the correct explanation of (A).

Explanation: The reaction of calcium oxide with water to produce sLaked lime releasing a large amount of heat is a combination reaction as the two reactants combine to form a single product.

Whereas, in a double displacement reaction, there will be two reactants and two products which are formed by the exchange of ions between the reactants.

Question 20.
Assertion (A): The decomposition reaction of silver chloride into silver and chlorine is an exothermic process.
Reason (R): Reactions in which energy is absorbed are known as endothermic reactions.

Question 21.
Assertion (A): Zinc and lead displace copper from their compounds.
Reason (R): Zinc and lead are more reactive than copper.

Competency-Based Questions (CBQs)

Question 1.

During a chemical reaction atoms of one element do not change into those of another element. Nor do atoms disappear from the mixture or appear from elsewhere. Actually, chemical reactions involve the breaking and making of bonds between atoms to produce new substances.

To demonstrate a reaction, 2 g of silver chloride is taken in a china dish and placed in sunlight.
(A) What will you observe after some time?
(B) What is this reaction known as?
(C) Write the balanced chemical equation for this reaction.
(D) Give reasons for the observations.

Question 2.
Whitewash is a very low-cost type of paint made from slaked lime (calcium hydroxide) and chalk (whiting). Chalk is calcium carbonate. Slaked lime turns into chalk by reacting with carbon dioxide in the air over several days. This causes crystallization, which binds and strengthens the coating. Various other additives can be used.

Solid calcium oxide reacts vigorously with water to form calcium hydroxide, accompanied by liberation of heat. This process is called slaking of lime. Calcium hydroxide dissolves in water to form a solution called lime water. Which among the following is (are) true about slaking of lime and the solution formed?
(I) It is an endothermic reaction.
(II) It is an exothermic reaction.
(III) The pH of the resulting solution will be more than seven.
(IV) The pH of the resulting solution will be less than seven.
(a) (I) and (II)
(b) (II) and (III)
(c) (I) and (IV)
(d) (III) and (IV)
(b) (II) and (III)

Explanation: Slaking of lime is an exothermic reaction because a large amount of heat is produced during the reaction. The heat can be felt by touching the beaker from the outside. The resulting compound Ca(OH)2, which is also called slaked lime, turns red litmus solution to blue and hence, proves it to be a basic solution. Thus, the pH of this solution will be more than seven.

Question 3.
Shalini was quite interested in observing the changes that take place during chemical reactions but was always afraid of entering the chemistry lab. When she spoke to her chemistry teacher regarding this, the teacher suggested that she should perform a simple experiment under her guidance to overcome her fear and at the same time she could observe the changes that take place during a chemical reaction.

She took about 2 g of ferrous sulphate crystals in a dry boiling tube and heated it over the
flame of a burner. She noticed change of colour of the ferrous sulphate crystals and could also smell the characteristic odour of burning sulphur.
(A) What change in colour did Shalini observe?
Shalini observed that the green colour of ferrous sulphate crystals changed to white as it loses water when heated.
FeSO4.7H2O → FeSO4 + 7H2O

(B) Why did Shalini get the characteristic odour of burning sulphur?

(C) What type of reaction takes place when ferrous sulphate is heated?
The type of reaction taking place is the thermal decomposition reaction. The chemical equation for the reaction taking place is:

(D) Give another example of such type of reactions.

Question 4.
The production of hydrogen from water via electrolysis is a clean process, resulting in only oxygen being produced as a by-product. If the electricity required to split the water into hydrogen and oxygen is supplied via a renewable energy source then the process is environmentally benign.The water electrolysis hydrogen (oxygen) plant is equipment that electrolyzes water to produce hydrogen and oxygen by using lye as an electrolyte.

Electrolysis of water is a decomposition reaction. The mole ratio of hydrogenand oxygen gases liberated during the electrolysis of water is:
(a) 1:1
(b) 2:1
(c) 4:1
(d) 1:2
(b) 2:1

Explanation: The balanced chemical equation for the electrolysis of water is:

The mole ratio of hydrogen and oxygen gases Liberated during electrolysis of water is 2:1 by volume.

In a decomposition reaction, a compound is broken down into its simpler forms. During electrolysis, water is broken down into oxygen gas and hydrogen gas due to the passage of electric current through it.

Question 5.
Redox reactions are an important class of reactions. The oxidation and reduction reactions always occur simultaneously, such class of chemical reactions is named as the redox reaction or Oxidation-Reduction reaction.

The substance getting reduced in a chemical reaction is known as the oxidizing agent, while a substance that is getting oxidized is known as the reducing agent. The activity in which copper powder is taken in a china dish and heated helps in understanding redox reactions.
(A) What happens when copper powder is heated in a china dish? Explain your observation.
When copper powder is heated in a china dish, the surface of copper powder is coated with black copper oxide as oxidation of copper takes place by addition of oxygen to copper.
2Cu + O2 → 2CuO

(B) What will you observe if hydrogen gas is passed over the heated material obtained in (A) above?
When hydrogen gas is passed over heated material CuO, the black coating on the surface turns brown as the reverse reaction takes place and copper is formed.
CuO + H2 → Cu + H2O

(C) Identify the substance oxidized and substance reduced in the reaction at (B) above.

(D) Identify the correct statement:
In the reaction between lead sulphide and hydrogen peroxide shown by the equation below,
PbS + 2H2O2 → PbSO4 + 4H2O,
(a) Lead sulphide Is reduced and Hydrogen peroxide is oxidized.
(b) Lead sulphide is oxidized and Hydrogen peroxide is reduced.
(c) Lead sulphate is oxidized and water is reduced.
(d) Lead sulphate is reduced and water is oxidized.

Question 6.
Rancidification is the process of complete or incomplete oxidation or hydrolysis of fats and oils when exposed to air, light, or moisture or by bacterial action, resulting in unpleasant taste and odor. Specifically, it is the hydrolysis or autoxidation of fats into short-chain aldehydes and ketones, which are objectionable in taste and odor. When these processes occur in food, undesirable odors and flavors can result.

Which of the following gases can be used for the storage of fresh sample of an oil for a long time?
(a) Carbon dioxide or oxygen
(b) Nitrogen or oxygen
(c) Carbon dioxide or helium
(d) Helium or nitrogen
(d) Helium or nitrogen

Explanation: Inert gases like helium or nitrogen both can be used for the storage of fresh sample of oil for a Long time, as they do not react with most elements, including oxygen. Thus these gases create an inert environment for the oil and prevent its reaction (oxidation) with any element in the environment. Hence, stopping it from becoming rancid.

Question 7.
A student takes two test tubes. In the first test tube, he takes lead nitrate solution and in the second he takes a few zinc granules. He adds potassium iodide solution to lead nitrate solution in the first test tube. He adds dilute sulphuric acid in the second test tube containing zinc granules.
(A) What is observed in the first test tube on adding potassium iodide solution?

(c) Both (II) and (III)

Explanation: When potassium iodide solution is added to lead nitrate solution in a test tube, a yellow precipitate of Lead iodide is formed. The equation of the reaction taking place is:

Pb(NO3)2(aq) + 2KI(aq) → PbI2(s) + 2KNO3(aq)

(B) Select the correct observations:
When dilute sulphuric acid is added to a few zinc granules in the second test tube,
(I) Bubbles of hydrogen gas can be seen around the zinc granules.
(II) Bubbles of carbon dioxide can be seen around zinc granules.
(IV) Colour of solution changes to blue,
(a) Only (I)
(b) Both (I) and (III)
(c) Both (II) and (III)
(d) (I), (III) and (IV)
(b) Both (I) and (III)

Explanation: When diluting sulphuric acid is added to zinc granules in a conical flask, the equation of the reaction taking place is:
Zn(s) + H2SO4(aq) → ZnSO4(aq)+ H2(g)

(C) Select the incorrect statement(s):
(I) Both the reactions are accompanied by a change in colour.
(II) A precipitate is formed in the first test tube only.
(III) Gas is evolved in the second test tube only.
(IV) Both the reactions are examples of double displacement reactions.
(a) Both (I) and (III)
(b) Both (I) and (IV)
(c) Both (II) and (III)
(d) Both (I) and (II)

(D) Suppose we add dil hydrochloric acid in place of sulphuric acid in the second test tube. Select the correct observation:
(a) Chlorine gas will be evolved.
(b) The test tube will become cold as heat is absorbed during this reaction.
(c) Hydrogen gas will be evolved.
(d) A precipitate of zinc chloride will be formed

(E) The type of reaction taking place when water is added slowly to a small amount of calcium oxide in a beaker is:
(I) Combination Reaction
(II) Displacement reaction
(III) Exothermic reaction
(IV) Endothermic reaction
(a) Both (I) and (III)
(b) Both (II) and (III)
(c) Both (I) and (IV)
(d) Both (II) and (IV)

Question 8.
You must have seen that your mother stores fried food items such as boondi raita, chips, mixture, banana chips and other such items properly. This is because their smell and taste change due to the oxidation of fried food items and food becomes unfit for human consumption.

Why are anti-oxidants added to fat and oil-containing food items?
Anti-oxidants are added to fat and oil-containing food items to prevent their oxidation which is known as rancidity which makes food smell bad and changes its taste.

Question 9.
Chemical reaction, a process in which one or more substances, the reactants, are converted to one or more different substances, the products. Substances are either chemical elements or compounds. A chemical reaction rearranges the constituent atoms of the reactants to create different substances as products.

Chemical reactions must be distinguished from physical changes. Physical changes include changes of state, such as ice melting to water and water evaporating to vapour. If a physical change occurs, the physical properties of a substance will change, but its chemical identity will remain the same. However, if water, as ice, liquid, or vapour, encounters sodium metal (Na), the atoms will be redistributed to give the new substances molecular hydrogen (H2) and sodium hydroxide (NaOH). By this, we know that a chemical change or reaction has occurred.
(A) Which of the following are physical changes?
(I) Melting of wax
(II) Burning of wax
(III) Rusting of iron
(IV) Evaporation of water
(a) Both (I) and (III)
(b) Both (II) and (III)
(c) Both (I) and (IV)
(d) Both (II) and (IV)
(c) Both (I) and (IV)

Explanation: Melting of wax and evaporation of water are physical change as they undergo only change in their physical states without any change in their chemical composition. Whereas, burning of wax is a chemical change as carbon dioxide and water are formed when wax is burned. Rusting of iron is also a chemical change as iron undergoes oxidation in the presence of moisture to form rust or iron oxide.

(B) A chemical reaction does not involve:
(a) Formation of new substances having entirely different properties than that of the reactants
(b) Breaking of old chemical bonds and formation of new chemical bonds
(c) Rearrangement of the atoms of reactants to form new products
(d) Changing of the atoms of one element into those of another element to form new products

(C) Quick lime is used in whitewashing because
(a) It is cheap
(b) It forms limestone with water which has a nice color.
(c) It forms slaked lime with water which reacts with atmospheric carbon dioxide to form limestone.
(d) It is easy to use

(D) Which of the following are endothermic processes?
(I) Burning of natural gas
(II) Dilution of an acid
(III) Evaporation of water
(IV) Sublimation of camphor (crystals)
(a) (I) and (II)
(b) (II) and (III)
(c) (IV) and (IV)
(d) (III) and (IV)

(E) The following reaction is used for the preparation of oxygen gas in the laboratory

Which of the following statement about the reaction is correct?
(a) It is a displacement reaction and endothermic in nature.
(b) it is a decomposition reaction and exothermic in nature.
(c) It is a decomposition reaction and endothermic in nature.
(d) It is a photochemical decomposition reaction and exothermic in nature.
((c) It is a decomposition reaction and endothermic in nature.

Explanation: It is a decomposition reaction as a single reactant splits up into two products, namely, KCl and O2, by absorbing energy in the form of heat.

It is an endothermic reaction as heat is absorbed in this reaction.

Question 10.
Many materials over time can be prone to corrosion and wear Iron is one such metal. Having a protective later and proper preparation can certainly help materials last longer and have other properties integrated into it.

A substance X used for coating iron articles is added to a blue solution of a reddish-brown metal Y. the colour of the solution gets discharged. Identify X and Y and also the type of reaction.
We are given that the metal Y is reddish brown in colour. This metal is copper and the blue solution of Y is copper sulphate. Also, zinc is used in protecting iron articles and this process is called galvanisation. As Zinc is more reactive than copper it displaces copper from its salt solution, copper sulphate.
Zn + CUSO4 → ZnSCO4 + Cu
So, X is zinc, while Y is copper.

Question 11.
Double displacement reactions may be defined as the chemical reactions in which one component each of both the reacting molecules is exchanged to form the products. During this reaction, the cations and anions of two different compounds switch places, forming two entirely different compounds.

Double displacement reactions generally take place in aqueous solutions in which the ions precipitate and there is an exchange of ions.

Double displacement reactions can be further classified as neutralization and precipitation reactions.
(A) What is the precipitate formed on mixing the solution of barium chloride and sodium sulphate?
(a) Barium sulphate
(b) Sodium chloride
(c) Barium sulphite
(d) Sodium sulphite
(a) Barium Sulphate

Explanation: When a solution of barium chloride is mixed with a solution of sodium sulphate, a precipitate of barium sulphate is formed along with sodium chloride.
BaCl2(aq) + Na2SO4(aq) → BaSO4(s) + NaCl(aq)

(I) lead (II) iodide precipitates out of the solution as a yellow solid
(II) Potassium nitrate precipitates out of the solution as a yellow solid
(IV) Exchange of lead and potassium ions takes place
(a) Both (I) and (III)
(b) Both (II) and (III)
(c) Both (I) and (IV)
(d) Both (II) and (IV)

(C) Identify the precipitate obtained by the reaction between lead nitrate and sodium sulphate.
(a) PbS
(b) Pb(SO4)2
(c) PbSO4
(d) NaNO2
(c) PbSO4
Explanation: Lead nitrate reacts with sodium sulphate solution to form a precipitate of lead sulphate and sodium nitrate.
Pb(NO3)2(aq)+ Na2SO4(aq) → PbSO4(s) + 2NaNO3(aq)

This is a double displacement reaction as the exchange of lead and sodium ions is taking place.

(D) Which one of the following is true about a double displacement reaction?
(I) Electrolysis of water is an example of this reaction.
(II) Two compounds exchange ions to form new compounds.
(III) Only a single product is formed.
(IV) Reaction between magnesium oxide and dilute hydrochloric acid is an example for this reaction.
(a) Both (I) and (II)
(b) Both (I) and (III)
(c) Both (II) and (III)
(d) Both (II) and (IV)

(E) Identify the incorrect statement regarding double displacement reactions:
(a) All double displacement reactions are precipitation reactions.
(b) All neutralization reactions between acids and bases are double displacement reactions
(c) The reaction between vinegar and baking soda is an example of a double displacement reaction.
(d) Reaction between silver nitrate solution and sodium chloride solution is an example of a double displacement reaction.

Question 12.
Thermite is a pyrotechnic composition of metal powder fuel and metal oxide. When ignited by heat, thermite undergoes an exothermic oxidation-reduction reaction. Most varieties are not explosive but can create brief bursts of high temperature in a small area. Its form of action is similar to that of other fuel-oxidizer mixtures, such as black powder. Thermites have diverse compositions. Fuels include aluminium, magnesium, titanium, zinc, silicon, and boron. Aluminium is common because of its high boiling point. Oxidizers include boron(III) oxide, silicon(IV) oxide, chromium(III) oxide, manganese(IV) oxide, iron(III) oxide, iron(II, III) oxide, copper(II) oxide, and lead(ll,IV) oxide.

In this reaction mention the substance getting oxidized and the substance getting reduced.
Fe2O3 + 2Al → Al2O3 + 2Fe
Oil and fat containing food items are flushed with nitrogen while packing them as nitrogen is an inert gas and prevents fried food materials from getting rancid.

Question 13.
A synthesis or combination reaction is a reaction in which simple compounds combine to make a more complex one. The opposite of a combination reaction is a decomposition reaction in which a single substance splits into two or more substances. We also have a single displacement reaction (in which a more reactive element displaces a less reactive element from its compound) and a double displacement reaction (in which the exchange of ions takes place between two compounds). Having a thorough understanding of the types of reactions will be useful for predicting the products of an unknown reaction.
(A) A student performed several experiments and then noted down his observations in a tabular form as given below:

 S.No. Observation Conclusion Regarding the type of Reaction Taking Place (I) When copper powder is heated in a china dish, the surface of the copper powder turns black Combination Reaction (II) Hydrogen gas is . evolved when Iron reacts with dil. HCl. Decomposition Reaction (III) A black precipitate is formed along with sulphuric acid solution when hydrogen sulphide gas is passed through copper sulphate solution Double Displacement Reaction (IV) When electricity is passed through molten aluminium chloride aluminium metal is formed along with a gas. Displacement Reaction

Select the option that correctly describes the conclusions made by the student regarding type of reaction taking place:
(a) Both (I) and (II)
(b) Both (I) and (III)
(c) Both (II) and (III)
(d) (I), (III) and (IV)
(d) Both (III) and (IV)

Explanation : When barium chloride solution is added to copper sulphate soLution, a white precipitate of barium sulphate is formed alongwith copper chloride solution.

This is an example of precipitation reaction as a precipitate of barium sulphate is formed. It is also a double displacement reaction as the Ba2+ and Cu2+ ions form new compounds by exchanging their ions. The equation of the reaction talcing place is:
BaCl2(aq) + CuSO4(aq) → BaSO4(s) + CuCl2(aq)

(B) When a metal X, which is used for coating iron articles, is added to a blue solution of a reddish brown metal Y, the color of the solution gets discharged.
Select the option which correctly identifies the metals X and Y and the type of reaction taking place.

(C) The type of reaction taking place when barium chloride solution is added to copper sulphate solution is:
(I) Combination reaction
(II) Displacement reaction
(III) Double Displacement reaction
(IV) Precipitation reaction
(a) Only (I)
(b) Only (II)
(c) Both (II) and (IV)
(d) Both (III) and (IV)

(D) Identify the incorrect statement:
(a) Burning of natural gas is a decomposition reaction.
(b) Burning of hydrogen gas in air is a combination reaction
(c) Reaction between most metals and dilute hydrochloric acid is a displacement reaction.
(d) Reaction between an acid and a base is an example of double displacement reaction.

(E) Which of the following statement(s) are correct?
(I) The precipitation reactions produce insoluble salts.
(II) Neutralization reactions are single displacement reactions.
(III) Decomposition reactions can be carried out only in presence of heat or light.
(IV) Displacement reactions are opposite of combination reactions.
(a) Only (I)
(b) Only (II)
(c) Both (I) and (III)
(d) Both (II) and (IV)
(a) Only (I)

Explanation: Precipitation reactions are the reactions in which an insoluble substance or precipitate is formed. Neutralization reactions are the reactions between an acid and a base and are double displacement reactions. Decomposition reactions require energy in the form of heat, light or electricity. Decomposition reactions are the opposite of combination reactions.

Question 1.
What happens when sodium sulphate solution is added to barium chloride solution?
When sodium sulphate solution is added to barium chloride solution, a white precipitate of barium sulphate is formed.
The equation of the reaction taking place is:
Na2SO4((aq) + BaCl2(aq) →BaSO4(s) + 2NaCl(aq)

Question 2.
An aqueous solution of metal nitrate P reacts with sodium bromide solution to form yellow ppt of compound Q which is used in photography. Q on exposure to sunlight undergoes decomposition reaction to form metal present in P along with reddish-brown gas. Identify P & Q.
As the compound Q is formed by the reaction between P (metal nitrate solution) and sodium bromide solution, Q is silver bromide which is used in photography.

Further, Q undergoes decomposition in the presence of sunlight to form silver and bromine gas. As silver is formed above, the metal nitrate is silver nitrate.

P – silver nitrate (AgNO3)
Q – silver bromide (AgBr).

Question 3.
What can be seen when a strip of copper metal is placed in a solution of silver nitrate?
When a strip of copper metals is placed in a solution of silver nitrate, copper displaces silver from silver nitrate solution as copper is a more reactive metal than silver. Copper nitrate is formed with a shiny greyish-white deposit of silver on the copper strip.
2AgNO3 + Cu → Cu(NCO3)2 + 2Ag

Question 4.
Name and state the law which is kept in mind when we balance chemical equations.
The law which is kept in mind when we balance chemical equations is the law of conservation of mass which states that “Matter can neither be created nor be destroyed”. It means that the total mass of atoms of reactants = the total mass of atoms of products, as atoms can neither be created nor be destroyed.

Question 5.
Hydrogen being a highly inflammable gas and oxygen being a supporter of combustion, yet water, a compound made up of hydrogen and oxygen is used to extinguish fire. Why?
The compound made up of hydrogen and oxygen is water (H20) which has properties that are different from properties of H2 and O2 as it is formed by the chemical reaction between hydrogen and oxygen gases. While hydrogen and oxygen are gases at room temperature, water is a liquid at room temperature.

Question 6.
If copper metal is heated over a flame, it develops a coating. What is the colour and composition of the coating?

Question 7.
Write a balanced chemical equation to represent the following reaction: carbon monoxide reacts with hydrogen gas at 340 atm to form methyl alcohol.

Question 8.
Write a balanced chemical equation for the reaction between sodium chloride and silver nitrate indicating the physical state of the reactants and the products.
When silver nitrate solution is added to sodium chloride solution, a white precipitate of silver chloride is formed along with sodium nitrate solution.
AgNO3(aq) + NaCl(aq) → AgCl(s) + NaNO3(aq)

Question 9.
Complete and balance the following:
Fe2O3 + Al →

## MCQ Questions for Class 11 Chemistry Chapter 7 Equilibrium with Answers

Check the below NCERT MCQ Questions for Class 11 Chemistry Chapter 7 Equilibrium with Answers Pdf free download. MCQ Questions for Class 11 Chemistry with Answers were prepared based on the latest exam pattern. We have provided Equilibrium Class 11 Chemistry MCQs Questions with Answers to help students understand the concept very well.

## Equilibrium Class 11 MCQs Questions with Answers

MCQ On Equilibrium Class 11 Question 1.
The solubility of Ca3​(PO4​​)2​ in water is y mol/L. Its solubility product is:
(a) 6y²
(b) 36 y4
(c) 64 y5
(d) 108 y5

Explanation:

= (3y)³ × (2y)²
= 27 y³ × 4y²
= 108 y5

Buffer pH Calculator makes it easy for you to determine the theoretical yield value of the chemical reaction in fraction of seconds with steps.

Equilibrium Class 11 MCQ Question 2.
A physician wishes to prepare a buffer solution at pH = 3.85 that efficiently resists changes in pH yet contains only small concentration of the buffering agents. Which of the following weak acids together with its sodium salt would be best to use?
(a) 2, 5-Dihydroxy benzoic acid (pKa = 2.97)
(b) Acetoacetic acid (pKa = 3.58)
(c) m-Chlorobenzoic acid (pKa = 3.98)
(d) p-Chlorocinnamic acid (pKa = 4.41)

Answer: (b) Acetoacetic acid (pKa = 3.58)
Explanation:
For small concentration of buffering agent and for maximum buffer capacity
[Salt]/ [Acid] ≈ 1
i.e., pH = pKa

MCQ On Chemical Equilibrium Class 11 Question 3.
Which of the following aqueous solutions will have highest pH?
(a) NaCl
(b) CH3COONa
(c) Na2CO3
(d) NH4Cl

Explanation:
NaCl is salt of strong acid and strong base so it has pH of about 7.
NH4Cl is salt of strong acid and weak base so it has pH is much less than 7.
CH3​COONH4 is salt of weak acid and weak base so it has pH of about 7.
Na2​CO3 is salt of weak acid and strong base so it has pH is much greater than 7.

Equilibrium MCQ Class 11 Question 4.
What is the pH of a 0.10 M solution of barium hydroxide, Ba (OH)2?
(a) 11.31
(b) 11.7
(c) 13.30
(d) None of these

Explanation:
pH = 13.30
Barium hydroxide is a strong base for both stages of dissociation:
Ba (OH)2(s) → Ba2+ + 2OH
So the solution will have 0.20 M hydroxide ions. Now use the auto dissociation product for water:
[H+][OH] = 1.0 × 10-14M
[OH] = 2.0 × 10-1M
[H+] = 5.0 × 10-14M
And then pH = −log10 ([H+] = 5.0 × 10-14)
= 13.30.

MCQ Of Equilibrium Class 11 Question 5.
Which of the following oxides is not expected to react with sodium hydroxide?
(a) CaO
(b) SiO2
(c) BeO
(d) B2O3

Explanation:
CaO being a basic oxide does not react with NaOH, however SiO2 (acidic oxide), BeO (amphoteric oxide) and Br2O3 (acidic oxide) react with NaOH.

Class 11 Chemistry Chapter 7 MCQ Question 6.
The pH of a 10-10 M NaOH solution is nearest to
(a) 10
(b) 7
(c) 4
(d) -10

Explanation:
pOH= −log [OH]
= −log 10-10
= 10 log 10
= 10pH + pOH
= 14pH
= 14−pOH
= 14−10
= 4

Chemical Equilibrium MCQs Class 11 Question 7.
A weak acid HX has the dissociation constant 1 × 10-5 M. It forms a salt NaX on reaction with alkali. The degree of hydrolysis of 0.1 M solution of NaX is
(a) 0.0001%
(b) 0.01%
(c) 0.1%
(d) 0.15%

Explanation:
NaX: Salt of weak acid, strong base.
⇒ α = (√Kh/c)
= √ (Kw)/ (KaC)
= (10-14)/(10-5×0.1)
= 10-4
⇒ % hydrolysis = 0.01%

MCQ On Chemical Equilibrium With Answers Question 8.
When equal volumes of 0.1 M NaOH and 0.01 M HCl are mixed, the hydroxide ion concentration is
(a) 7.0
(b) 1.04
(c) 12.65
(d) 2.0

Explanation:
When equal volumes of 0.1 M NaOH and 0.01 M HCl are mixed, the hydroxide ion concentration is
(0.1 – 0.01)/(2)
​= 0.045 M
The pOH of the solution is pOH = −log [OH]
= −log 0.045
= 1.35
The pH of the solution is pH = 14 − pOH
= 14 − 1.35
= 12.65

MCQ Questions For Class 11 Chemistry Chapter 7 Question 9.
Concentration of the Ag+ ions in a saturated solution of Ag2C2O4 is 2.2 x 10-4 mol L-1. Solubility product of Ag2C2O42 is
(a) 2.66 × 10-12
(b) 4.5 × 10-11
(c) 5.3 × 10-12
(d) 2.42 × 10-8

Explanation:
[Ag+] = 2.2 × 10-4 mol L-1
[C2​O42-] = 0.5[Ag+] = 0.5 × 2.2 × 10-4 mol L-1 = 1.1 × 10-4 mol L-1
Ksp ​=[Ag+]² [C2O42-​]Ksp
= (2.2 × 10-4 mol L-1)² × 1.1 × 10-4 mol L-1
Ksp = 5.3 × 10-12

Chemical Equilibrium Class 11 MCQ Question 10.
In a reversible chemical reaction at equilibrium, if the concentration of any one of the reactants is doubled, then the equilibrium constant will
(a) Also be Doubled
(b) Be Halved
(c) Remain the Same
(d) Become One-Fourth

Explanation:
Equilibrium constants are not changed if you change the concentrations of things present in the equilibrium. The only thing that changes an equilibrium constant is a change of temperature.

The position of equilibrium is changed if you change the concentration of something present in the mixture. According to Le Chateliers Principle, the position of equilibrium moves in such a way as to tend to undo the change that you have made.

According to Le Chateliers Principle, if you increase the concentration of Reactant, for example, the position of equilibrium will move to the right to decrease the concentration of reactant again.

Chapter 7 Chemistry Class 11 MCQs Question 11.
When a neutral atom undergoes oxidation, the atoms oxidation state
(a) Decreases as it gains electrons
(b) Decreases as it loses electrons
(c) Increases as it gains electrons
(d) Increases as it loses electrons

Answer: (d) Increases as it loses electrons
Explanation:
The acronym “OILRIG” can be used to remember this: Oxidation is Losing electrons, Reduction is Gaining electrons. Therefore, when an atom undergoes oxidation, it loses electrons. This makes its net charge more positive, so its oxidation state increases.

Class 11 Chemistry Chapter 7 MCQ With Answers Question 12.
Concentration of the Ag-4 ions in a saturated solution of Ag2C2O4 is 2.2 × (a) 10-4 mol L-1. Solubility product of Ag2C2O4 is
(b) 2.66 × 10-12
(c) 4.5 × 10-11
(d) 5.3 × 10-12
2.42 × 10-8

Explanation:
[Ag+] = 2.2 × 10-4 mol L-1
[C2​O42-] = 0.5[Ag+] = 0.5 × 2.2 × 10-4 mol L-1 =1.1×10-4 mol L-1
Ksp ​= [Ag+]² [C2​O42-​] Ksp
= (2.2 × 10-4 mol L-1)² × 1.1 × 10-4 mol L-1
Ksp = 5.3 × 10-12

Class 11 Chemistry Equilibrium MCQ Question 13.
Among the following the weakest Bronsted base is
(a) F
(b) Cl
(c) Br
(d) I

Explanation:
According to this theory, an acid is a proton donor and a base is a proton acceptor. Every strong Bronsted acid has a weak conjugate base and every strong base has a weak conjugate acid. The acidity increases in halogen group atoms,
HF < HCl < HBr < HI.
So, HI is highly acidic and their conjugate bases decrease in order F > Cl > Br > I.

Chemical Equilibrium Class 11 MCQ Questions Question 14.
A certain buffer solution contains equal concentration of X and HX. The ka for HX is 10-8. The pH of the buffer is
(a) 3
(b) 8
(c) 11
(d) 14

Explanation:
ka kb = kw
kb = 10-8
ka × 10-8 = 10-14
ka = 10-6 = [H+]
pH = −log [H+]
pH = −log 10-6
= 6pH + pOH
= 14 pOH
= 14−6
= 8

Class 11 Equilibrium MCQ Question 15.
What is the pH of a 0.10 M solution of barium hydroxide, Ba (OH)2?
(a) 11.31
(b) 11.7
(c) 13.30
(d) None of these

Explanation:
pH =13.30
Barium hydroxide is a strong base for both stages of dissociation:
Ba (OH)2(s) → Ba2+ + 2OH
So the solution will have 0.20 M hydroxide ions. Now use the auto dissociation product for water:
[H+][OH] = 1.0×10-14M
[OH] = 2.0 × 10-1M
[H+] = 5.0 × 10-14M
And then pH = −log10 ([H+] = 5.0 × 10-14)
= 13.30.

Chemical Equilibrium MCQs Question 16.
Solubility of M2S salt is 3.5 × 10-6 then find out solubility product.
(a) 1.7 × 10-6
(b) 1.7 × 10-16
(c) 1.7 × 10-18
(d) 1.7 × 10-12

Explanation:
Let ”s“ be the solubility of salt M2​S which undergoes dissociation as follows :-
M2​S ⇌ 2M+ +S-2
Initial concentration 1 0 0
Concentration at equilibrium 1-s 2s s
Hence, the solubility product (Ksp) = (s) × (2s)²
Therefore, Ksp = 4 × s³
Or Ksp​​ = 4× (3.5×10-6
⇒ Ksp
= 1.7 × 10-16

Ch 7 Chemistry Class 11 MCQ Question 17.
Among the following hydroxides, the one which has the lowest value of Ksp at ordinary temperature (about 25°C ) is
(a) Mg (OH)2
(b) Ca(OH)2
(c) Ba(OH)2
(d) Be(OH)2

Explanation:
Be(OH)2 ​has the lowest value of Ksp at ordinary temperature because Be2+ ion is smaller than the other metal ions in the group, which results in a tighter bond with the 0H ions, thus much lower solubility.

The solubility of a hydroxide of group 2 elements increases down the group because as you go down the group size of metal increases thereby increasing the bond length and decreasing bond energy.

Chemical Equilibrium MCQ Class 11 Question 18.
Which of the following mixtures in aqueous solution of equimolar concentration acts as a buffer solution?
(a) HNO3 and NaOH
(b) H2SO4 and KOH
(c) NH4OH(excess) + HCl
(d) CH3COOH and NaOH(excess)

Explanation:
A mixture of ammonium hydroxide and HCl react to form ammonium chloride. This also contains unreacted ammonium hydroxide.
NH4​ OH + HCl → NH4Cl + H2O
Thus, the resulting mixture of (NH4OH+NH4Cl) is a basic buffer solution. It contains a mixture of weak base ammonium hydroxide and its salt (ammonium chloride) with strong acid (HCl).
It is used in a qualitative analysis of group III radicals.
A mixture of HNO3 and NaOH is a mixture of strong acid and strong base similarly a mixture of
H2​SO4 and KOH is also a mixture of strong acid and strong base, thus they do not form buffer solution.
Similarly, in option 4 mixture will form a strong base and salt of strong base weak acid hence it will not form a buffer solution.

Chemical Equilibrium MCQ With Answers Question 19.
Which of the following aqueous solutions will have highest pH?
(a) NaCl
(b) CH3COONa
(c) Na2CO3
(d) NH4Cl

Explanation:
NaCl is salt of strong acid and strong base so it has pH of about 7.
NH4​Cl is salt of strong acid and weak base so it has pH is much less than 7.
CH3COONH4 is salt of weak acid and weak base so it has pH of about 7.
Na2​CO3 is salt of weak acid and strong base so it has pH is much greater than 7.

Question 20.
Amines behave as
(a) Lewis Acids
(b) Lewis Base
(c) Aprotic Acid
(d) Neutral Compound

Explanation:
R−NH2 (Amines) behaves as a Lewis base because it is capable of donating a lone pair of electron.

We hope the given NCERT MCQ Questions for Class 11 Chemistry Chapter 7 Equilibrium with Answers Pdf free download will help you. If you have any queries regarding CBSE Class 11 Chemistry Equilibrium MCQs Multiple Choice Questions with Answers, drop a comment below and we will get back to you soon.

## MCQ Questions for Class 12 Chemistry Chapter 4 Chemical Kinetics with Answers

Check the below NCERT MCQ Questions for Class 12 Chemistry Chapter 4 Chemical Kinetics with Answers Pdf free download. MCQ Questions for Class 12 Chemistry with Answers were prepared based on the latest exam pattern. We have provided Chemical Kinetics Class 12 Chemistry MCQs Questions with Answers to help students understand the concept very well.

## Chemical Kinetics Class 12 MCQs Questions with Answers

Chemical Kinetics Class 12 MCQ Question 1.
In chemical equation H2 (g) + I2 (g) $$\rightleftharpoons$$ 2HI (g) the equilibrium constant Kp depends on
(a) total pressure
(b) catalyst used
(c) amount of H2 and I2
(d) temperature

Class 12 Chemistry Chapter 4 MCQ Question 2.
If the rate of a reaction is expressed by, rate = A [A]² [B], the order of reaction will be
(a) 2
(b) 3
(c) 1
(d) 0

Percent concentration and molarity are the most commonly used solution.

MCQ On Chemical Kinetics Question 3.
In a reaction, 2X → Y, the concentration of X decreases from 0.50 M to 0.38 M in 10 min. What is the rate of reaction in Ms-1 during this interval ?
(a) 2 × 10-4
(b) 4 × 10-2
(c) 2 × 10-2
(d) 1 × 10-2

MCQ On Chemical Kinetics Class 12 Question 4.
The decomposition of dimethyl ether is a fractional order reaction. The rate is given by rate =k(PCH3OCH3)3/2. If the pressure is measured in bar and time in minutes, then what are the units of rate and rate constant?
(a) bar min-1, bar2 min-1
(b) bar min-1, bar1/2 min-1
(c) bar1/2 min-1, bar2 min-1
(d) bar min-1, bar1/2 min-1

Answer: (b) bar min-1, bar1/2 min-1

Chemical Kinetics Class 12 MCQ Questions Question 5.
A reaction in which reactants (R) are converted into products (P) follows second order kinetics. If concentration of R is increased by four times, what will be the increase in the rate of formation of P?
(a) 9 times
(b) 4 times
(c) 16 times
(d) 8 times

MCQ Of Chemical Kinetics Class 12 Question 6.
Which of the following, is an example of a fractional order reaction?
(a) NH4NO2 → N2 + 2H2O
(b) NO + O3 → NO2 + O2
(c) 2NO + Br2 → 2NOBr
(d) CH3CHO → CH4 + CO

Answer: (d) CH3CHO → CH4 + CO

Chemical Kinetics MCQ Questions And Answers Question 7.
The unit of rate constant for the reaction
2H2 + 2NO → 2H2O + N2
which has rate = K|H2||NO|², is
(a) mol L-1 s-1
(b) s-1
(c) mol-2 L² s-1
(d)mol L-1

MCQ On Chemical Kinetics Class 12 Pdf Question 8.
Fora reaction x + y → z, rate ∝ |X|. What is (i) moleculariiy and (ii) order of reaction?
(a) (i)2, (ii) 1
(b) (i)2,(ii) 2
(c) (i) 1, (ii) 1
(d) (i) 1, (ii) 2

Chemical Kinetics MCQ Questions Question 9.
For a reaction nx – y → z the rate of reaction becomes twenty seven times when the concentration of X is increased three times. What is the order of the reaction?
(a) 2
(b) 1
(c) 3
(d) 0

MCQ Of Chapter 4 Chemistry Class 12 Question 10.
The rate constant of a reaction depends upon
(a) temperature of the reaction
(b) extent of the reaction
(c) initial concentration of the reactants
(d) the time of completion of reaction

Answer: (d) the time of completion of reaction

Chemical Kinetics MCQ With Answers Pdf Question 11.
The chemical reaction, 2O3 → 3O2 proceeds as
O3 $$\rightleftharpoons$$ O2 + |O| (fast)
|O| + O3 → 2O2 (slow)
The rate law expression will be
(a) Rate = k [O] [O3]
(b) Rate = k [O3]² [O2]-1
(c) Rate = k [O3
(d) Rate = k [O2] [O]

Answer: (b) Rate = k [O3]² [O2]-1

Class 12 Chemical Kinetics MCQ Question 12.
The unit of rate and rate constant are same fora
(a) zero order reaction
(b) first order reaction
(c) second order reaction
(d) third order reaction

Chapter 4 Chemistry Class 12 MCQs Question 13.
The number of molecules of the reactants taking part in a single step of the reaction is indicative of
(a) order of a reaction
(b) molecuiarity of a reaction
(c) fast step of the mechanism of a reaction
(d) half-life of the reaction

Answer: (b) molecuiarity of a reaction

MCQ Chemical Kinetics Class 12 Question 14.
Fora unimolecular reaction
(a) the order and molecuiarity of the slowest step are equal to one
(b) molecuiarity of the reaction can be zero, one or two
(c) molecuiarity of the reaction can be determined only experimentally
(d) more than one reacting species are involved in one step

Answer: (a) the order and molecuiarity of the slowest step are equal to one

MCQ Questions For Class 12 Chemistry Chapter 4 Question 15.
The overall rate of a reaction is governed by
(a) the rate of fastest intermediate’step
(b) the sum total of the rates of all intermediate steps
(c) the average of the rates of all the intermediate steps
(d) the rate of slowest intermediate step

Answer: (d) the rate of slowest intermediate step

Question 16.
The order of reaction is decided by
(a) temperature
(b) mechanism of reaction as well as relative concentration of reactants
(c) molecularity
(d) pressure

Answer: (b) mechanism of reaction as well as relative concentration of reactants

Question 17.
Rate constant in case of first order reaction is
(a) inversely proportional to the concentration units
(b) independent of concentration units
(c) directly proportional to concentration units
(d) inversely proportional to the square of concentration units

Answer: (b) independent of concentration units

Question 18.
Half life period of a first order reaction is 10 min. What percentage of the reaction will be completed in 100 min?
(a) 25%
(b) 50%
(c) 99.9%
(d) 75%

Question 19.
In pseudo unimolecular reactions
(a) both the reactants are present in low concentration
(b) both the reactants are present in same concentration
(c) one of the reactant is present in excess
(d) one of the reactant is non-reactive

Answer: (c) one of the reactant is present in excess

Question 20.
A first order reaction takes 40 min for 30% decomposition. What will be t12?
(a) 77.7 min
(b) 52.5 min
(c) 46.2 min
(d) 22.7 min

Question 21.
A first order reaction has a rate constant 1.15 × 10-3s-1. How long time will 5 g of this reactant take to reduce to 3 g?
(a) 444 s
(b) 400 s
(c) 528 s
(d) 669 s

Question 22.
Radioactive disintegration is an example of
(a) zero order reaction
(b) first order reaction
(c) second order reaction
(d) third order reaction

Question 23.
A plot of log (a – x) against time t is a straight line. This indicates that the reaction is of
(a) zero order
(b) first order
(c) second order
(d) third order

Question 24.
Rate of which reaction increases with temperature?
(a) Exothermic reaction
(b) Endothermic reaction
(c) (a) and (b) both
(d) None of the above

Answer: (c) (a) and (b) both

Question 25.
The activation energy in a chemical reaction is defined as
(a) the difference in energies of reactants and products
(b) the sum of energies of reactants and products
(c) the difference in energy of intermediate complex with the average energy of reactants and products
(d) the difference in energy of intermediate complex and the average energy of reactants

Answer: (d) the difference in energy of intermediate complex and the average energy of reactants

We hope the given NCERT MCQ Questions for Class 12 Chemistry Chapter 4 Chemical Kinetics with Answers Pdf free download will help you. If you have any queries regarding Chemical Kinetics CBSE Class 12 Chemistry MCQs Multiple Choice Questions with Answers, drop a comment below and we will get back to you soon.

## MCQ Questions for Class 11 Chemistry Chapter 4 Chemical Bonding and Molecular Structure with Answers

Check the below NCERT MCQ Questions for Class 11 Chemistry Chapter 4 Chemical Bonding and Molecular Structure with Answers Pdf free download. MCQ Questions for Class 11 Chemistry with Answers were prepared based on the latest exam pattern. We have provided Chemical Bonding and Molecular Structure Class 11 Chemistry MCQs Questions with Answers to help students understand the concept very well.

## Chemical Bonding and Molecular Structure Class 11 MCQs Questions with Answers

Chemical Bonding Class 11 MCQ Question 1.
The bond length between hybridised carbon atom and other carbon atom is minimum in
(a) Propane
(b) Butane
(c) Propene
(d) Propyne

Explanation:
The C – C bond length = 1.54 Å, C = C bond length = 1.34 Å and C ≡ C bond length = 1.20 Å.
Since propyne has a triple bond, therefore it has minimum bond length.

Chemical Bonding And Molecular Structure MCQ Question 2.
The number of nodal planes present in s × s antibonding orbitals is
(a) 1
(b) 2
(c) 0
(d) 3

Explanation:
In an antibonding molecular orbital, most of the electron density is located away from the space between the nuclei, as a result of which there is a nodal plane (i.e, a plane at which the electron density is zero) between the nuclei.

Class 11 Chemistry Chapter 4 MCQ With Answers Question 3.
The hybrid state of sulphur in SO2 molecule is :
(a) sp²
(b) sp³
(c) sp
(d) sp³d

Explanation:
The hybridisation of sulphur in SO2 is sp². Sulphur atom has one lone pair of electrons and two bonding domains. Bond angle is <120° and molecular geometry is V-shape, bent or angular

Class 11 Chemistry Chapter 4 MCQ Question 4.
Which one of the following does not have sp² hybridised carbon?
(a) Acetone
(b) Acetic acid
(c) Acetonitrile
(d) Acetamide

Explanation:
Acetonitrile does not contain sp² hybridized carbon.

MCQ Questions For Class 11 Chemistry Chapter 4 Question 5.
Which of the following will have the lowest boiling point?
(a) 2-MethylButane
(b) 2-MethylPropane
(c) 2,2-Dimethylpropane
(d) n-Pentane

Explanation:
Boiling point increases with increase in molecular mass. For the compounds with the same molecular mass, boiling point decreases with an increase in branching.
The molecular mass of 2-Methylbutane: 72 g mol-1
The molecular mass of 2-Methylpropane: 58 g mol-1
The molecular mass of 2, 2-Dimethylpropane: 72 g mol-1
The molecular mass of 2-Methylbutane: 72 g mol-1
2-Methylpropane has the lowest molecular mass among all of the given compounds.
Thus, 2-Methylpropane has the lowest boiling point among the given options.

My question is that how to calculate bond order for open and closed sheel.

Chemical Bonding And Molecular Structure Class 11 MCQ Question 6.
Among the following the maximum covalent character is shown by the compound
(a) MgCl2
(b) FeCl2
(c) SnCl2
(d) AlCl3

Explanation:
We know that, extent of polarisation ∝ covalent character in ionic bond. Fajans rule states that the polarising power of cation increases, with increase in magnitude of positive charge on the cation Therefore, polarising power ∝ charge of cation.

The polarising power of cation increases with the decrease in the size of a cation. Therefore, polarising (power) ∝ (1)/ (size of cation)
Here the AlCl3 is satisfying the above two conditions i.e., Al is in +3 oxidation state and also has small size. So it has more covalent character.

MCQ Of Chemical Bonding Class 11 Question 7.
Among the following mixtures, dipole-dipole as the major interaction, is present in
(a) benzene and ethanol
(b) acetonitrile and acetone
(c) KCl and water
(d) benzene and carbon tetrachloride

Explanation:
Dipole-dipole interactions occur among the polar molecules. Polar molecules have permanent dipoles. The positive pole of one molecule is thus attracted by the negative pole of the other molecule. The magnitude of dipole-dipole forces in different polar molecules is predicted on the basis of the polarity of the molecules, which in turn depends upon the electro negativities of the atoms present in the molecule and the geometry of the molecule (in case of polyatomic molecules, containing more than two atoms in a molecule).

Ch 4 Chemistry Class 11 MCQ Question 8.
The value of n in the molecular formula BenAl2Si6O18 is
(a) 3
(b) 5
(c) 7
(d) 9

Explanation:
BenAl2Si6O18
The oxidation states of each element
Be = +2
Al = +3
Si = +4
O = -2
(2n) + (3 × 2) + (4 + 6) + (−2 × 18) = 0
or 2n + 30 − 36 = 0
or 2n = 6
or n = 3

MCQ On Chemical Bonding Class 11 Pdf Question 9.
Which of the following types of hybridisation leads to three dimensional geometry of bonds around the carbon atom?
(a) sp
(b) sp²
(c) sp³
(d) None of these

Explanation:
sp² hybrid structures have trigonal planar geometry, which is two dimensional.

Chemical Bonding MCQ Class 11 Question 10.
An atom of an element A has three electrons in its outermost orbit and that of B has six electrons in its outermost orbit. The formula of the compound between these two will be
(a) A3B6
(b) A2B3
(c) A3B2
(d) A2B

Explanation:
A has 3 electrons in outermost orbit and B has 6 electrons in its outermost orbits. So A can give three electrons to complete its octet and B needs 2 electrons to complete its octet. So 2 atoms of A will release 6 electrons and 3 atoms of B will need six electrons to complete their octet
So, the formula will be A2​B3

Class 11 Chemistry Ch 4 MCQ Question 11.
The maximum number of hydrogen bonds that a molecule of water can have is
(a) 1
(b) 2
(c) 3
(d) 4

Explanation:
Each water molecule can form a maximum of four hydrogen bonds with neighboring water molecules. The two hydrogens of the water molecule can form hydrogen bonds with other oxygens in ice, and the two lone pair of electrons on oxygen of the water molecule can attract other hydrogens in ice. Hence, 4 possible hydrogen bonds.

MCQ Questions On Chemical Bonding Class 11 Question 12.
The number of types of bonds between two carbon atoms in calcium carbide is
(a) Two sigma, two pi
(b) One sigma, two pi
(c) One sigma, one pi
(d) Two sigma, one pi

Answer: (b) One sigma, two pi
Explanation:
A single bond between two atoms is always considered as sigma bond.
A double bond between two atoms is always considered as one sigma and one pi bond
A triple bond between two atoms is always considered as one sigma bond and two pi bonds.
So according to the given structure CaC2 (Calcium carbide) has 1 sigma and 2 pi bonds

Class 11 Chemical Bonding MCQ Question 13.
Based on lattice enthalpy and other considerations which one the following alkali metals chlorides is expected to have the higher melting point?
(a) RbCl
(b) KCl
(c) NaCl
(d) LiCl

Explanation:
The highest melting point will be NaCl, it is because, the lattice energy decreases as the size of alkali metal increases so going down the group the melting point decreases, but due to the covalent bonding in LiCl, its melting point is lower than NaCl and so NaCl is expected to have maximum melting point in the alkali chlorides.​

MCQ Of Chapter 4 Chemistry Class 11 Question 14.
Dipole-induced dipole interactions are present in which of the following pairs?
(a) H2O and alcohol
(b) Cl2 and CCl4
(c) HCl and He atoms
(d) SiF4 and He atoms

Answer: (c) HCl and He atoms
Explanation:
HCl is polar (μ ≠ 0) and He is non-polar (μ = 0) gives dipole-induced dipole interaction.

Chemistry Class 11 Chapter 4 MCQ Question 15.
Among the following mixtures, dipole-dipole as the major interaction, is present in
(a) benzene and ethanol
(b) acetonitrile and acetone
(c) KCl and water
(d) benzene and carbon tetrachloride

Explanation:
Dipole-dipole interactions occur among the polar molecules. Polar molecules have permanent dipoles. The positive pole of one molecule is thus attracted by the negative pole of the other molecule. The magnitude of dipole-dipole forces in different polar molecules is predicted on the basis of the polarity of the molecules, which in turn depends upon the electro negativities of the atoms present in the molecule and the geometry of the molecule (in case of polyatomic molecules, containing more than two atoms in a molecule).

Chapter 4 Chemistry Class 11 MCQ Question 16.
The charge/size ratio of a cation determines its polarizing power. Which one of the following sequences represents the increasing order of the polarizing order of the polarizing power of the cationic species, K+, Ca++, Mg2+, Be2+?
(a) Ca2+ < Mg2+ < Be+ < K+
(b) Mg2+ < Be2+ < K+ < Ca2+
(c) Be2+ < K+ < Ca2+ < Mg2+
(d) K+ < Ca2+ < Mg2+ < Be2+

Answer: (d) K+ < Ca2+ < Mg2+ < Be2+
Explanation:
High charge and small size of the cations increases polarisation.
As the size of the given cations decreases as
K+ > Ca2+ > Mg2+ > Be2+
Hence, polarising power decreases as K+ < Ca2+ < Mg2+ < Be2+

Chapter 4 Chemistry Class 11 MCQs Question 17.
The species having pyramidal shape is
(a) SO3
(b) BrF3
(c) SiO32-
(d) OSF2

Explanation:
The species having a pyramidal shape according to VSEPR theory is OSF2. The central S atom has 3 bonding domains (one S = O double bond and two S−F single bonds) and one lone pair of electrons.

The electron pair geometry is tetrahedral and molecular geometry is pyramidal. This is similar to the ammonia molecule.

MCQ Chemical Bonding Class 11 Question 18.
The structure of IF7 is
(a) Pentagonal bipyramid
(b) Square pyramid
(c) Trigonal bipyramid
(d) Octahedral

Explanation:
IF7 Hybridization is sp³d³
Structure is Pentagonal bipyramidal.

MCQ On Chemical Bonding Class 11 Question 19.
The outer orbitals of C in ethene molecule can be considered to be hybridized to give three equivalent sp² orbitals. The total number of sigma (s) and pi (p) bonds in ethene molecule is
(a) 1 sigma (s) and 2 pi (p) bonds
(b) 3 sigma (s) and 2 pi (p) bonds
(c) 4 sigma (s) and 1 pi (p) bonds
(d) 5 sigma (s) and 1 pi (p) bonds

Answer: (d) 5 sigma (s) and 1 pi (p) bonds
Explanation:
According to valence bond theory, two atoms form a covalent bond through the overlap of individual half-filled valence atomic orbitals, each containing one unpaired electron. In ethene, each hydrogen atom has one unpaired electron and each carbon is sp² hybridized with one electron each sp² orbital. The fourth electron is in the p orbital that will form the pi bond. The bond order for ethene is simply the number of bonds between each atom: the carbon-carbon bond has a bond order of two, and each carbon-hydrogen bond has a bond order of one.

MCQ On Chemical Bonding With Answers Pdf Question 20.
Which of the following is a linear molecule?
(a) ClO2
(b) CO2
(c) NO2
(d) SO2

Explanation:
The steric number of central atom of a linear molecule is two. It has two bonded atoms and zero lone pair. All the molecules have two bonded atoms. Thus, we need to work out the number of lone pairs.
In ClO2, the central atom Cl has 7 valence electrons. Four are used up to form 4 bonds with O atoms. Three are non-bonding electrons. Thus, along with an odd electron, it has a lone pair.
In CO2, the central C atom has 4 valence electrons. All are used up to form four bonds with O atoms. Thus, it has zero lone pair.
In NO2, the central N atom has 5 valence electrons. Four are used up to form bonds with oxygen atoms. Thus, one electron is left as an odd electron.
In SO2, the central S atom has 6 valence electrons. Four are used up to form bonds with oxygen atoms. Two nonbonding electrons form one lone pair.

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## Online Education for Acids, Bases and Salts Class 10 MCQs Questions with Answers

Acid Bases And Salts Class 10 MCQ Question 1.
What happens when the solution of an acid is mixed with the solution of a base in a test tube?
(I) The temperature of the solution increases
(II) The temperature of the solution decreases
(III) The temperature of the solution remains the same
(IV) Salt formation takes place
(a) Only (I)
(b) (I) and (III)
(c) (I) and (III)
(d) (I) and (IV)
(d) (I) and (IV)

Explanation: When an acid reacts with a base, a neutral salt is formed by the neutralisation process. As the neutralisation process is an exothermic reaction, the temperature of the solution increases.
Acid + Base → Salt + Water

Acids Bases And Salts Class 10 MCQ Question 2.
If 10 mL of H2SO4 is mixed with 10 mL of Mg(OH)2 of the same concentration, the resultant solution will give the following colour with a universal indicator:
(a) Red
(b) Yellow
(c) Green
(d) Blue
(c) Green.
Explanation: If 10 mL of H2SO4 is mixed with 10 mL of Mg(OH)2 of the same concentration, the resultant solution be MgS04 which is a neutral salt and universal indicator will give the green colour in this solution:

Related Theory:
When an acid reacts with a base it forms salt and water. As a result, acidic properties disappear The process is called neutralisation. For a neutral solution. pH is 7. The solution having pH 7 wilL turn green in colour in universal indicator.

This online pH calculator is designed to determine the pH of an aqueous solution of a given chemical compound.

Class 10 Science Chapter 2 MCQ Question 3.
Which of the following saLts does not contain water of crystatUsatlon?
(a) Blue vitriol
(b) Baking soda
(c) Washing soda
(d) Gypsum

Acid Base And Salts Class 10 MCQ Question 4.
A visually challenged student has to perform a lab test to detect the presence of acid in a given solution. The acid-base indicator preferred by him will be:
(a) Blue litmus
(b) Clove oil
(c) Red cabbage extract
(d) Hibiscus extract
(b) Clove oil
Explanation: Clove oil is an olfactory indicator. These are the substances that give one type of odour in an acidic medium so a visually challenged student prefers to use clove oil as an acid-base indicator.

As in basic solutions, the smell of clove oil disappears while the smell is retained when mixed with an acid, on the other hand, blue litmus, red cabbage extract and hibiscus extract wouLd not be used as acid-base indicators because in these indicators there will be a change in the colour.

Class 10 Acids Bases And Salts MCQ Question 5.
Baking soda is a mixture of:
(a) Sodium carbonate and acetic acid
(b) Sodium carbonate and tartaric acid
(c) Sodium hydrogen carbonate and tartaric acid
(d) Sodium hydrogen carbonate and acetic acid

MCQ Of Acid Base And Salts Class 10 Question 6.
Which of the following gives the correct increasing order of acid strength?
(a) Water < acetic acid < hydrochloric acid
(b) Water < hydrochloric acid < acetic acid
(c) Acetic acid < water < hydrochloric acid
(d) Hydrochloric acid < water < acetic acid

Ch 2 Science Class 10 MCQ Question 7.
What is observed when we pour a drop of acetic acid first on red and then on blue litmus papers?
(a) Red litmus paper becomes colourless and blue litmus paper remains blue.
(b) Red litmus paper turns blue and blue litmus paper remains blue.
(c) Red litmus paper remains red and blue litmus paper turns red.
(d) Red litmus paper turns blue and blue litmus paper turns red.

Class 10 Science Ch 2 MCQ Question 8.
Sodium hydrogen carbonate when added to acetic acid evolves a gas. Which of the following statements are true about the gas evolved?
(I) It turns lime water milky.
(II) It extinguishes a burning splinter.
(III) It dissolves in a solution of sodium hydroxide.
(IV) It has a pungent odour.
(a) (I) and (II)
(b) (I), (II) and (III)
(c) (II), (III) and (IV)
(d) (I) and (IV)
(b) (I), (II) and (III)

Explanation: Reaction of sodium hydrogen carbonate with acetic acid forms sodium acetate and water with carbon dioxide (CO2) gas.

CO2 does not have a pungent smell but it shows all the other three properties:

1. turns lime water milky,
2. is a non-supporter of combustion and
3. absorbed by strong alkalis such as NaOH.

MCQ Questions For Class 10 Science Chemistry Chapter 2 Question 9.
Common salt besides being used in the kitchen can also be used as the raw material for making:
(I) Washing soda
(II) Bleaching powder
(III) Baking soda
(IV)Slaked Urne
(a) (I) and (II)
(b) (I), (II) and (IV)
(c) (I) and (III)
(d) (I), (III) and (IV)

Acids Bases And Salts MCQ Question 10.
To protect against tooth decay we are advised to brush our teeth regularly. The nature of the toothpaste commonly used is:
(a) Acidic
(b) Neutral
(c) Basic
(d) Corrosive
(c) Basic

Explanation: The toothpaste commonly used is alkaline or basic in nature as they contain mild bases such as sodium fluoride or sodium bicarbonate in their composition.

The base reacts with the acid formed during bacterial action in the mouth and neutralises its bad effects. Thus, preventing tooth decay. So, they can neutralize the effect of extra acids being formed in the mouth cavity which are mainly responsible for tooth decay.

Related Theory
When we eat sweet things, the pH of our mouth falls below 5.5 (moderately acidic) as the oral bacteria release acid while acting on sugars present in our food. The acidic conditions are capable of corroding the enamel which is made up of calcium phosphate. This causes the tooth to decay.

MCQ Questions For Class 10 Science Chapter 2 Question 11.
Match the chemical substances given in Column I with their appropriate application given in Column II:

 Column I Column II (A) Bleaching Powder (1) Preparation of glass (B) Baking Soda (2) Production of H2 and Cl2 (C) Washing Soda (3) Decolourisation (D) Sodium Chloride (4) Antacid

Chapter 2 Science Class 10 MCQ Question 12.
Which of the following phenomena occur, when a small amount of acid is added to water?
(I) Ionisation
(II) Neutralisation
(III) Dilution
(IV)Salt formation
(a) (I) and (II)
(c) (II) and (III)
(b) (I) and (III)
(d) (II) and (IV)

Class 10 Chemistry Chapter 2 MCQ Question 10.
To protect against tooth decay we are advised to brush our teeth regularly. The nature of the toothpaste commonly used is:
(a) Acidic
(b) Neutral
(c) Basic
(d) Corrosive
(c) Basic

Explanation: The toothpaste commonly used is alkaline or basic in nature as they contain

Class 10 Acid Base And Salt MCQ Question 13.
A sample of soil is mixed with water and allowed to settle. The clear supernatant solution turns the pH paper yellowish-orange. Which of the following would change the colour of this pH paper to greenish-blue:
(a) Lemon juice
(b) Vinegar
(c) Common salt
(d) An antacid
(d) An antacid

Explanation: pH paper gives greenish-blue colour in a weak alkaline medium so antacid [Mg(OH)2] which is an alkaline compound will show greenish-blue color on pH paper.

Related Theory
Lemon fruit contains citric acid, vinegar has acetic acid and common salt is the neutral salt the clear super natant solution turns the pH paper yellowish-orange means the given sample of soil is acidic so it can be neutralised by base/alkaline solution.

MCQ On Acids Bases And Salts Class 10 Question 14.
Which of the following is not a mineral acid?
(a) Hydrochloric acid
(b) Citric acid
(c) Sulphuric acid
(d) Nitric acid

Class 10 Chapter 2 Science MCQ Question 15.
Which of the following is/are true when HCl(g) is passed through water?
(I) It does not ionise in the solution as it is a covalent compound.
(II) It ionises in the solution.
(III) It gives both hydrogen and hydroxyl ions in the solution.
(IV) It forms hydronium ion in the solution due to the combination of hydrogen ion with water molecule.
(a) Only (I)
(b) Only (III)
(c) (II) and (IV)
(d) (III) and (IV)
(c) (II) and (IV)

Explanation: HCl, is a polar covalent compound, easily ionises in water to form hydronium (H3O+) and chloride ions (Cl). HCl (a strong acid) ionises completely in water to produce H+ and Cl ions. H+ ion combines with water molecules to produce hydronium ions.

Question 16.
Which among the following is not a base?
(a) NaOH
(b) KOH
(c) NH4OH
(d) C2H5OH
(d) C2HsOH
Explanation: C2H5OH is not a base. C2H5OH is an organic compound with -OH functional group that is known as alcohol. It cannot give OH ions in its solution. It cannot dissociate ions in a solution. Thus, it cannot be a basic compound.

Question 17.
Identify the correct representation of reaction occurring during the chloralkali process.
(a) 2NaCl(l) + 2H2O(l) → 2NaOH(l) + Cl2(g) + H2(g)
(b) 2NaCl(l) + 2H2O(aq) → 2NaOH(aq) + Cl2(g) + H2(aq)
(c) 2NaCl(aq) + 2H2O(l) → 2NaOH(aq) + Cl2(aq) + H2(aq)
(d) 2NaCl(aq) + 2H2O(l) → 2NaOH(aq) + Cl2(g) + H2(g)

Question 18.
Which of the following statements is true for acids?
(a) Bitter and change red litmus to blue.
(b) Sour and change red litmus to blue.
(c) Sour and change blue litmus to red.
(d) Bitter and change blue litmus to red.

Question 19.
Zinc granules on treating with an acid X, form zinc sulphate (ZnSO4) salt along with the evolution of a gas Y, which burns with a pop sound when brought near to a burning candle. Identify acid X and gas evolved Y.
(a) X-sulphuric acid and Y-oxygen gas
(b) X-hydrochloric acid and Y-oxygen gas
(c) X-sulphuric acid and Y-hydrogen gas
(d) X-hydrochloric acid and Y-hydrogen gas [Diksha]
(c) X-sulphuric acid and Y-hydrogen gas

Explanation: When an acid reacts with a metal, hydrogen gas is liberated. In the given reaction, when dilute sulphuric acid reacts with zinc granules, hydrogen gas is liberated and zinc sulphate solution is formed:

The presence of hydrogen gas is tested by bringing a lighted candle near it. When a lighted candle is brought near the test tube containing hydrogen gas, it burns with a ‘pop’ sound making a little explosion.

Hence, acid X is sulphuric acid and gas Y is hydrogen gas.

Question 20.
Which of the following solutions in water does not conduct electricity?
(a) Hydrochloric acid
(b) Sodium chloride
(c) Glucose
(d) Sulphuric acid [Diksha]
(c) Glucose

Explanation: The aqueous solution of an acid conducts electricity because of the presence of charged particles called ‘ions’ in it. When hydrochloric acid (HCl) is dissolved in water, its aqueous solution contains hydrogen ions (H+) and chloride ions (Cl). These ions carry electric currents. So, due to the presence of H+ and Cl ions, a solution of hydrochloric acid conducts electricity.

On the other hand, the hydrogen-containing compound such as glucose is not categorized as acid because it does not produce hydrogen ions or some other ions when dissolved in water and hence does not conduct electricity. Therefore, the answer is glucose.

Question 21.
Which of the following will turn phenolphthalein pink?
(a) NaOH(aq)
(b) HCl(aq)
(c) CH3COOH(aq)
(d) H2O

Question 22.
Which one of the following is not a use of washing soda:
(a) Sodium carbonate (washing soda) is used in glass, soap and paper industries.
(b) It is used in the manufacture of sodium compounds such as borax.
(c) Sodium carbonate can be used as a clean¬ing agent for domestic purposes.
(d) It is used for disinfecting water.
(d) It is used for disinfecting water.

Explanation: The compound that is used for disinfecting water is bleaching powder. How¬ever, washing soda is used for removing the permanent hardness of water.

Question 23.
The approximate pH values of four salts is given below. Select the row(s) containing the correct information.

 Name of Salt PH (I) Potassium Sulphate 10 (II) Ammonium nitrate 5 (III) Sodium acetate 3 (IV) Sodium hydrogen carbonate 8

(a) Both (I) and (II)
(b) Both (II) and (III)
(c) Both (III) and (IV)
(d) Both (II) and (IV)

Question 24.
Zinc granules on treating with a substance X, form a salt sodium zincate along with the evolution of a gas Y which burns with a pop sound when brought near a burning candle. Identify the substance X and gas evolved Y.

 X Y (a) Acetic acid Hydrogen (b) Sodium hydroxide Hydrogen (c) Sodium hydroxide Oxygen (d) Zinc hydroxide Hydrogen

(b) X is Sodium hydroxide and Y is hydrogen.

Explanation: When zinc granules react with sodium hydroxide, salt sodium zincate is formed along with hydrogen gas, which burns with a pop sound.

The equation of the reaction taking place is:
2NaOH(aq) + Zn(s) → Na2ZnO2(aq) + H2(g)

Question 25.
Which of the following salts belong to the same family of salts?
(I) sodium chloride and sodium acetate
(II) calcium sulphate, magnesium sulphate
(III) sodium carbonate and sodium hydrogen -carbonate
(IV) sodium chloride and magnesium sulphate
(a) Both (I) and (II)
(b) Both (I) and (III)
(c) (I), (II) and (III)
(d) (I), (III) and (IV)

Question 26.
A student noted his observations regarding the acidic or basic nature of salts as below:
(I) Sodium chloride is a neutral salt
(II) Ammonium chloride is a basic salt
(III) Sodium carbonate is a neutral salt
(IV) Copper sulphate is an acidic salt Select the incorrect observations:
(a) Both (I) and (III)
(b) Both (II) and (III)
(c) Both (I) and (IV)
(d) Both (II) and (IV)
(b) Both (II) and (III)

Explanation: The salts of strong acids and strong bases give neutral solutions. Therefore, sodium chloride is a neutral salt as it is obtained from sodium hydroxide (a strong base) and hydrochloric acid (a strong acid).

The salts of strong acids and weak bases give acidic solutions. Therefore, ammonium chloride and copper sulphate are acidic salts as ammonium chloride is obtained from ammonium hydroxide (a weak base) and hydrochloric acid (a strong acid), and copper sulphate is obtained from copper hydroxide (a weak base) and sulphuric acid (a strong acid).

The salts of weak acids and strong bases give basic solutions. Therefore, sodium carbonate is a basic salt as it is obtained from carbonic acid (a weak acid) and sodium hydroxide(a strong base).

### Assertion Reasoning questions Class 10 Science Chapter 2

For the following questions, two statements are given – one labelled Assertion (A) and the other labeled Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given below:
(a) Both (A) and (R) are true and (R) is the correct explanation of the (A).
(b) Both (A) and (R) are true, but (R) is not the correct explanation of the (A).
(c) (A) is true, but (R) is false.
(d) (A) is false, but (R) is true.

Question 27.
Assertion,(A): HCl gas does not change the colour of dry blue litmus paper.
Reason (R): Acids always produce hydrogen ions.
(b) Both (A) and (R) are true, but (R) is not the correct explanation of the (A).

Explanation: HCl gas does not change the colour of dry litmus paper but changes colour of moist litmus paper as acids produce hydrogen ions only in solution.

Question 28.
Assertion (A): Generally, the colour of indicators changes in a particular pH range.
Reason (R): Indicators are weak acids or weak base and exhibit different colours in molecular form and ionic form.
(a) (A) and (R) are true and (R) is the correct explanation of the (A).

Explanation: Since indicators are weak acids or weak bases, their percentage of existence in molecular state and in ionized state depends on the strength of acidic/basic/neutral solution to which they are added. Hence their colours change at a particular pH range.

Question 29.
Assertion (A): Zinc reacts with sodium hydroxide solution and hydrogen gas is evolved.
Reason (R): All metals react with bases to evolve hydrogen gas.

Question 30.
Assertion (A): While diluting an acid, water is slowly added to acid with constant stirring.
Reason (R): The process of dissolving an acid in water is a highly exothermic reaction.

Question 31.
Assertion (A): Metal oxides are acidic in nature.
Reason (R): Calcium hydroxide reacts with carbon dioxide to form a salt and water.
(d) (A) is false, but (R) is true.

Explanation: The reaction of calcium hydroxide with carbon dioxide to form a salt and water is similar to the reaction between an acid and a base. Therefore, non-metal oxides are acidic in nature.

Question 32.
Assertion (A): When copper sulphate crystals are heated in a dry boiling tube, they turn white.
Reason (R): Water of crystallization is the number of water molecules present in one formula unit of a salt.
(b) Both (A) and (R) are true but (R) is not the correct explanation of (A).

Explanation: Copper sulphate crystals that seem to be dry contain water of crystallisation. When we heat the crystals, this water is removed and the salt turns white.
CUSO4.5H2O → CuSO4 + 5H2O

Question 33.
Assertion (A): When copper oxide is added to dilute hydrochloric acid, the colour of the solution becomes blue-green.
Reason (R): Copper (II) chloride is formed.
(a) (A) and (R) are true and (R) is the correct explanation of the (A).

Explanation: When copper oxide is added to dilute hydrochloric acid, the colour of the solution becomes blue-green due to the formation of Copper (II) chloride, which is blue-green in colour.

(Competency Based Questions (CBQs))

Question 1.
A chemistry student pLaced a strip of blue litmus paper and a strip of red litmus paper in a glass dish. Then she added a drop of dilute sulphuric acid to each strip of litmus paper. She observed that the blue litmus paper turned red, but the red litmus paper did not change color. Next, she placed a drop of sodium hydroxide (NaOH) on other strips of blue and red litmus paper. This time, the red litmus paper turned blue, but the blue litmus paper did not change. Finally, she put a drop of distilled water on strips of blue and red litmus paper. Neither strip changed color. She repeated the tests several times with the same results. The student concluded that acids turn blue litmus paper red; bases, such as sodium hydroxide, turn red litmus paper blue. As water did not affect either red or blue litmus paper, she reasoned that water was not an acid or a base, but a neutral substance.

Keeping these results in mind, the student poured a little sodium hydroxide into a beaker containing red and blue litmus paper. Then she added hydrochloric acid (HCl) drop by drop until the solution became neutral. She determined that a new, neutral substance had formed in the beaker. The substance was table salt, or sodium chloride (NaCl), which is one of many salts formed from an acid and a base.
(A) If a drop of an unknown substance turns blue litmus paper red, but does not change red litmus paper, what will be the substance – an acid or a base?

(B) When strips of blue and red litmus paper are put in a beaker filled with a clear solution, neither litmus paper changes colour. What can you say about the solution?
The solution must be neutral.

(C) Based on the results of this experiment, when would salt be formed?

(D) What happens when nitric acid is added to egg shell?
Calcium carbonate is main component of egg shell so when we add nitric acid to egg shell, it reacts with calcium carbonate to form soluble calcium nitrate and water with brisk effervescence of carbon dioxide gas.
CaCO3(s) + 2HNO3(aq) → Ca(NO3)2(aq) + CO2(g) + H2O

Question 2.
When we smile, our teeth become visible. So, we should ensure that we have a beautiful set of teeth as it makes our smile even more beautiful! Tooth enamel is the thin outer covering of the tooth. This tough shell is the hardest tissue in the human body. Enamel covers the crown which is the part of the tooth that’s visible outside of the gums.

Calcium phosphate is present in tooth enamel. Its nature is:
(a) Basic
(b) Acidic
(c) Neutral
(d) Amphoteric
(a) Basic

Explanation: Calcium phosphate Ca3(PO4)2 is a basic salt, as it is formed by the combination of a weak acid (phosphoric acid) and a slightly stronger base (calcium hydroxide).

Question 3.
Patrick read about an industrial process for the electrolysis of sodium chloride solutions.
It is the technology used to produce chlorine and sodium hydroxide which are commodity chemicals required by industry. 35 million tons of chlorine were prepared by this process in 1987. Industrial-scale production began in 1892. Usually, the process is conducted on a brine (an aqueous solution of NaCl), in which case NaOH, hydrogen, and chlorine are formed. When using calcium chloride or potassium chloride, the products contain calcium or potassium instead of sodium. Related processes are known that use molten NaCl to give chlorine and sodium metal or condensed hydrogen chloride to give hydrogen and chlorine.
(A) Name the process referred to in the above passage.
The process referred to in the passage is chlor-alkali process because of the products formed – chlor for chlorine and alkali for sodium hydroxide.

(B) Where are the products of the above process produced?

(C) Write the chemical equation for the reaction taking place in the process.
The chemical equation for the reaction taking place is:
2NaCl(aq) + 2H2O → 2NaOH(aq) + Cl2(g) + H2(g)

(D) How is bleaching powder prepared from one of the products formed in this industrial process?

Question 4.
Neetu’s friend suffered a fracture in her foot while riding her bicycle. She had to be admitted to the nursing home and the doctor plastered her foot.

The chemical formula for Plaster of Paris is:
(a) CaSO4.2H2O
(b) CaSO4.H2O
(c) CaSO4.$$\frac{1}{2}$$H2O
(d) 2CaSO4.H2O
(c) CaSO4. $$\frac{1}{2}$$ H2O

Explanation: Chemical name of Plaster of Paris is calcium sulphate hemihydrate. It is written in this form because two formula units of CaSO4 share one molecule of water.

Related Theory
When gypsum is heated at 373K, it loses water molecules.

It is a white powder used by doctors for supporting fractured bones. It is also used for making toys, materials for decoration and for making surfaces smooth.

Question 5.
Sabina studied in history about Mahatma Gandhi’s Dandi March and came to know that sodium chloride was an important symbol in our struggle for freedom. She started exploring from the internet as she was anxious to know what all we can do with this salt other than using it as a table salt to make food tasty. Table salt is also used to preserve food, facilitates transport of nutrients and oxygen and is used as raw material to form various salts.

Based on the understanding of the given passage and the related studied concepts, answer the following questions:
(A) Name two salts of daily use for which common salt (sodium chloride) is the raw material.
(B) Draw a diagram of chloralkali process and write its equation.

Question 6.
While performing experiments in chemistry lab, one should always wear a laboratory coat and be very careful while performing experiments. Some students have the bad habit of creating nuisance for other students which distracts the students and may cause serious accidents such as spilling of acid or can cause burn injuries.

If a few drops of concentrated acid accidentally spills over the hand of a student, what should be done?
(a) Wash the hand with a saline solution
(b) Wash the hand immediately with plenty of water and apply a paste of sodium hydrogen carbonate
(c) After washing with plenty of water, apply a solution of sodium hydroxide on the hand
(d) Neutralise the acid with a strong alkali
(b) Wash the hand immediately with plenty of water and apply a paste of sodium hydrogen carbonate

Explanation: In such an accident, washing the hands with water will dilute the acid and wash it out. Any remaining acid will be neutralized with sodium hydrogen carbonate (baking soda) as it is a base. This will minimize the effect of damage caused by acid to the skin.

Remember, too strong a base (like NaOH) can be corrosive.

Question 7.
Take about 2 mL of dilute NaOH solution in a test tube and a small amount of copper oxide in a beaker. Add two drops of phenolphthalein solution in the test tube. Add dilute HCl solution in both the test tube and the beaker drop by drop while stirring. Now add a few drops of NaOH to the mixture in the test tube.
(A) When two drops of phenolphthalein solution are added to the test tube,
(a) The solution turns pink in colour
(b) The solution turns colourless
(c) The solution turns red
(d) The solution turns yellow
(a) The solution turns pink in colour

Explanation: Phenolphthalein is a colourless reagent which is used as an indicator as it changes the colour to pink in a basic solution. As dilute NaOH is a basic solution, its colour changes to pink on adding a few drops of phenolphthalein solution.

(B) @Four students recorded their observations on adding dilute HCL to the beaker containing copper oxide. Select the correct observation:

 Student Observation-I Observation-II (a) Solution becomes colourless Copper oxide dissolves (b) Solution becomes blue-green in colour Copper oxide dissolves (c) Solution becomes blue green in colour Copper oxide is formed as a precipitate (d) Solution becomes colourless Copper chloride solution is colourless

(C) Select the correct observation(s):
When dilute HCl solution is added to the test tube drop by drop (after adding two drops of phenolphthalein solution) and then a few drops of NaOH solution are added to this mixture:
(I) The solution turns coLourless on adding dilute HCl
(II) The solution turns pink on adding dilute HCl
(III) The solution turns colourless again on adding NaOH to the mixture.
(IV) The solution turns pink again on adding NaOH to the mixture
(a) Both (I) and (III)
(b) Both (II) and (III)
(c) Both (I) and (IV)
(d) Both (II) and (IV)

(D) Identify the option that correctly describes the products formed in the test tube and beaker on adding dilute HCl:

 Test Tube Beaker (a) Sodium chloride + hydrogen Copper chloride + hydrogen (b) Sodium chloride + water Copper chloride + hydrogen (C) Sodium chloride + hydrogen Copper chloride + water (d) Sodium chloride + water Copper chloride + water

(d) Test Tube: Sodium chloride + water; Beaker: Copper chloride + water

Explanation: The products formed in the test is sodium chloride and water and that in beaker is copper chloride and water.

When sodium hydroxide reacts with dilute hydrochloric acid, it forms sodium chloride and water:
When copper oxide reacts with HCl, it forms copper chloride and water:
CuO(s) + 2HCl(aq) → CuCl2(aq) + H2O(l)

(E) Select the incorrect statement(s):
(I) Reaction of sodium hydroxide with dilute hydrochloric acid is a displacement reaction.
(II) Reaction of copper oxide with dilute hydrochloric acid is a double displacement reaction.
(III) Reaction of sodium hydroxide with dilute hydrochloric acid is a neutralization reaction.
(IV) Reaction of copper oxide with dilute hydrochloric acid is a neutralization reaction.
(a) Only (I)
(b) Only (II)
(c) Both (I) and (IV)
(d) Both (II) and (III)
(a) Only (I)

Explanation: Reaction of sodium hydroxide with dilute hydrochloric acid is a neutralization reaction which is also a double displacement reaction as products are formed by the exchange of ions between the reactants.

Similarly, the reaction of copper oxide with dilute hydrochloric acid is also a neutralization reaction which is also a double displacement reaction.

Whereas in a displacement reaction, a more reactive substance displaces a less reactive substance from its compound as in the reaction between a metal such as zinc and dilute hydrochloric acid.

Question 8.
Sumit along with his friend went to a nearby shopping mall. They were standing under a tree when an ant stung his friend on his hands due to which his friend’s hand was painting a lot.

Name the acid along with its chemical formula present in ant sting.
The acid present in ant sting is methanoic acid (formic acid). The chemical formula is HCOOH. Explanation: When an ant stings, it leaves formic acid (Methanoic acid) which causes pain and irritation. To get relief from the sting, mild base like baking soda can be applied on the stung.

Question 9.
Take about 1g solid NaCl in a clean and dry test tube and set up the apparatus as shown in Figure.

Add some concentrated sulphuric acid to the test tube.
(A) The gas produced in the test tube is:
(a) Hydrogen
(b) Hydrogen chloride
(c) Hydrogen sulphide
(d) Sulphur dioxide
(b) Hydrogen chioride
Explanation: When concentrated sulphuric acid is added to sodium chloride, the following reaction takes place:

2NaCl+ H2SO4→ Na2SO4 + 2HCl

(B) A student tested the gas coming out of the delivery tube first with dry blue litmus paper and then with wet litmus paper and noted down the following observations. Select the correct observation:

 Dry Blue Litmus Paper Wet Blue Litmus Paper (a) No change Turns red (b) Turns red No change (c) Turns red Turns red (d) No change No change

(C) If climate is humid, the gas evolved is passed through a guard tube containing:
(a) Calcium hydroxide
(b) Calcium carbonate
(c) Calcium sulphate
(d) Calcium chloride
(d) Calcium chloride

Explanation: During the preparation of hydrogen chloride gas, the gas is usually passed through the guard tube containing calcium chloride during humid climate, as calcium chloride is a good drying agent and absorbs moisture from the gas.

(D) Select the incorrect statement(s):
(I) Hydrogen ions in HCl are produced even in absence of water.
(II) Hydrogen ions can exist alone.
(III) Hydrogen ions exist after combining with water molecules.
(IV) Hydrogen ions in HCl are produced only in presence of water
(a) Only (I)
(b) Both (I) and (II)
(c) Both (I) and (III)
(d) Both (II) and (IV)
(b) Both (I) and (II)
Explanation: The separation of H+ ions from HCl molecules cannot occur in the absence of water.
HCl +H2O → H3O+ + Cl
Hydrogen ions cannot exist alone, but they exist after combining with water molecules. Thus hydrogen ions must always be shown as H+(aq) or hydronium ion (H30+).
H+ + H2O → H3O+

(E) Hydrogen ions must always be shown as H+(aq) or hydronium ion (H30+) as:
(a) Hydrogen ions combine with water to form hydronium ions
(b) Hydrogen gas dissociates into ions.
(c) All acids dissociate into hydrogen ions in presence of a base.
(d) Hydrogen ions separate from acids on passing electricity.

Question 10.
Acids and bases represent two important classes of chemical compounds. In every day life, acids and bases play a role in everything from the digestion of the foods you eat to the function of the medicine you take and even the cleaning products you use. Without acids and bases, many of the products in your home today would not have much use. Acids and bases are also important in atmospheric, geological, and physiological processes because they have unique chemical properties. Acids and bases have unique chemical properties because of the atomic composition of these compounds and how these compounds interact with other atoms and molecules.
The pH of some common substances is shown below:
(A) The nature of calcium phosphate present in tooth enamel is:
(a) Basic
(b) Amphoteric
(c) Acidic
(d) Neutral

(B) What is the pH value of saliva after meal?
(a) between 0 and 4
(b) between 4 and 5
(c) between 5 and 6
(d) between 6 and 7
(c) between 5 and 6

Explanation: The pH of saliva after meals is around 5.8 due to the increased activity of bacteria on the food that we eat.

(C) Given below are four statements. Select the incorrect statement(s):
(I) Pain and irritation during indigestion is due to the excess acid produced by the stomach.
(II) People use antacids to get rid of this pain which are bases.
(III) Milk of magnesia is an antacid as it is a mild acid.
(IV) Antacids neutralize the excess acid produced in the stomach.
(a) Only (I)
(b) Only (II)
(c) Only (III)
(d) (III) and (IV)
(c) Only (III)

Explanation: Antacids are bases which help in getting rid of the pain and irritation during indigestion by neutralizing the excess acid produced in the stomach. Milk of magnesia or magnesium hydroxide is a mild base that is used as an antacid.

(D) The pH level of the human body is:
(a) Less than 7, acidic
(b) Equal to 7, Neutral
(c) More than 7, basic
(d) None of the above

(E) A student tabulated the naturally occurring acidic substances and the acid contained in them.

 Natural Source Acid found (I) Vinegar Methanoic acid (II) Nettle sting Acetic acid (III) Tomato Oxalic acid (IV) Orange Citric acid

Select the option containing the correct acid found in them:
(a) Both (I) and (II)
(b) Both (III) and (IV)
(c) Both (II) and (IV)
(d) Both (I) and (III)
(b) Both (III) and (IV)

Explanation: Vinegar contains acetic acid, whereas nettle sting contains methanoic acid.

Question 11.
If you think the best way to put out a fire is by dousing it with water, you’d be surprised to know you’re wrong. As it turns out, not all fires are created equal, and there is more than one way to extinguish them safely. There are situations where you should not use water to deal with a fire at all. For example, an electrical fire.

Name the chemicals used in acid fire extinguishers and the gas that evolved from it when it is used?
The chemicals used in soda acid fire extinguishers are sodium hydrogen carbonate and sulphuric acid.
The gas evolved when the two reactants react is carbon dioxide which is used for extinguishing electrical fires.
The reaction taking place between the two chemicals is
2NaHCO3 + H2SO4 → Na2SO4 + 2CO2 + 2H2O

Question 12.
The reaction between MnO2 with HCl is depicted in the following diagram. It was observed that a gas with bleaching abilities was released.

(A) The chemical reaction between MnO2 and HCl is an example of:
(a) displacement reaction
(b) combination reaction
(c) redox reaction
(d) decomposition reaction.
(c) redox reaction

Explanation: When MnO2 reacts with HCl, the following reaction takes place in which chlorine gas is also evolved, which has bleaching properties.
MnO2 + 4HCl → MnCl2 + Cl2 + 2H2O

In this reaction, Hydrochloric acid is oxidized to chlorine and Manganese dioxide is reduced to manganese dichloride. As both oxidation and reduction are taking place in this reaction, it is a redox reaction.

(B) Chlorine gas reacts with ……………… to form bleaching powder.
(a) dry Ca(OH)2
(b) dil. solution of Ca(OH)2
(c) cone, solution of Ca(OH)2
(d) dry CaO
(a) dry Ca(OH)2
Explanation: Bleaching powder is produced by the action of chlorine on dry slaked lime [Ca(OH)2],
Ca(OH)2 + Cl2 → CaOCl2 + H2O

(C) Identify the correct statement from the following:
(a) MnO2 is getting reduced whereas HCl is getting oxidized
(b) MnO2 is getting oxidized whereas HCl is getting reduced.
(c) MnO2 and HCl both are getting reduced.
(d) MnO2 and HCl both are getting oxidized.
(a) Mn02 is getting reduced whereas HCl is getting oxidized.
Explanation: In the reaction between
MnO2 and HCl, MnO2 is getting reduced to manganese dichloride as it is losing oxygen atoms. Whereas, HCl is getting oxidized to chlorine by the removal of oxygen.

Related Theory
Oxidation is the addition of oxygen to a substance or the removal of hydrogen from a substance.
Reduction is the addition of hydrogen to a substance or removal of oxygen from a substance.
The oxidising agent is the substance that provides oxygen for oxidation or which removes hydrogen.
Reducing agent is the substance which provides hydrogen for reduction or which removes oxygen.

(D) In the above-discussed reaction, what is the nature of MnO2?
(a) Acidic oxide
(b) Basic oxide
(c) Neutral oxide
(d) Amphoteric oxide
(b) Basic oxide
Explanation: As MnO2 reacts with HCl to form salt, water and chlorine gas, it is a basic oxide since it reacts with an acid. Moreover, oxides of metals are basic in nature whereas oxides of non-metals are acidic in nature.

(E) What will happen if we take dry HCl gas instead of aqueous solution of HCl?
(a) Reaction will occur faster.
(b) Reaction will not occur.
(c) Reaction rate will be slow
(d) Reaction rate will remain the same.
(b) Reaction wiil not occur

Explanation: A substance shows its acidic properties only in presence of water as it is able to dissociate into H+ ions, which is responsible for its acidic properties.

So, if we use dry HCl, then no reaction will take place as HCl will not be able to dissociate into ion$as shown by the following reaction: HCl + H2O H3O+ + Cl Question 13. Frothing in Yamuna: The primary reason behind the formation of the toxic foam is high phosphate content in the wastewater because of detergents used in dyeing industries, dhobi ghats and households. Yamuna’s pollution level is so bad that parts of it have been labelled ‘dead’ as there is no oxygen in it for aquatic life to survive. (A) Predict the pH value of the water of river Yamuna if the reason for froth is high content of detergents dissolved in it. (a) 10-11 (b) 5-7 (c) 2-5 (d) 7 Answer: (a) 10-11 Explanation: Detergents are basic in nature having pH value of 10-11. As the froth has a high content of detergents dissolved in it, the pH value of water of river Yamuna will be 10 -11. (B) Which of the following statements is correct for the water with detergents dissolved in it? (a) low concentration of hydroxide ion (OH)and high concentration of hydronium ion (H3O+) (b) high concentration of hydroxide ion (OH) and low concentration of hydronium ion (H3O+) (c) high concentration of hydroxide ion (OH) as well as hydronium ion (H3O+) (d) equal concentration of both hydroxide ion (OH) and hydronium ion (H3O+). Answer: (b) high concentration of hydroxide ion (OH) and low concentration of hydronium ion (H3O+) Explanation: As detergents are basic in nature, the concentration of hydroxide ions will be high and the concentration of hydronium ions will be less. Related Theory When bases are dissolved in water, they dissociate into hydroxide ions. For example, NaOH(aq) → Na+(aq) + CH(aq) KOH(aq) → K+(aq) + OH(aq) (C) The table provides the pH value of four solutions P, Q, R and S  Solution PH Value P 2 Q 9 R 5 S 11 Which of the following correctly represents the solutions in increasing order of their hydronium ion concentration? (a) P > Q > R> S (b) P > S > Q > R (c) S < Q < R< P (d) S < P < Q < R Answer: (c) S < Q < R. < P Explanation: The pH of a substance is related to the concentration of hydrogen or hydronium ions. An acid has a high concentration of hydronium ions and a low pH value whereas a base has a high pH value and a low concentration of hydronium ions. So, we can say, lower the pH value, the more is the concentration of hydronium ions. Therefore, the hydronium ion concentration is least in S, followed by Q, R and then P which has the maximum concentration of hydronium ions. (D) High content of phosphate ion in river Yamuna may lead to: (a) decreased level of dissolved oxygen and increased growth of algae (b) decreased level of dissolved oxygen and no effect of the growth of algae (c) increased level of dissolved oxygen and increased growth of algae (d) decreased level of dissolved oxygen and decreased growth of algae Answer: (a) decreased level of dissolved oxygen and increased growth of algae Explanation: When the amount of phosphate ions in water increases, it leads to decreased level of dissolved oxygen which is harmful for the aquatic organisms. This leads to an increased growth of algae due to presence of nutrients. Related Theory Eutrophication is the process in which a water body becomes overly enriched with nutrients, leading to plentiful growth of simple plant life. The excessive growth (or bloom) of algae and plankton in a water body are indicators of this process. (E) If a sample of water containing detergents is provided to you, which of the following methods will you adopt to neutralize it? (a) Treating the water with baking soda (b) Treating the water with vinegar (c) Treating the water with caustic soda (d) Treating the water with washing soda Answer: (b) Treating the water with vinegar Explanation: As detergents are basic in nature, an acid will neutralize it. Out of the substances mentioned, only vinegar is acidic, as it is 5 – 8% solution of ethanoic acid in water. Very Short Answer Type Questions Question 1. What types of ions are formed: (a) when an acid is dissolved in water (b) when a base is dissolved in water? Answer: Question 2. ‘A’ is a soluble acidic oxide and ‘B’ is a soluble base. Compared to pH of pure water, what will be the pH of (a) solution of A (b) solution of B? Answer: pH of pure water is 7. As A is a soluble acid, its pH will be less than that of pure water whereas pH of B will be more than that of pure water as it is a soluble base. Question 3. When electricity is passed through a common salt solution, sodium hydroxide is produced along with the liberation of two gases “X” and “Y”. “X” burns with a pop sound whereas “Y” is used for disinfecting drinking water. Identify X and Y. Answer: The reaction is chlor-alkali process. As X burns with a pop sound, X is hydrogen gas. Y is chlorine gas which is used for disinfecting drinking water. Question 4. Which bases are called alkalis? Give one example of alkali. Answer: The bases that are soluble in water are called alkalies. One example of an alkali is sodium hydroxide, NaOH. Question 5. Name the acid and base that have com stituted the salt ammonium nitrate Answer: Question 6. Oxides of metals are basic while those of non-metals are acidle, Explain. Answer: Oxides of metals are basic as they react with acids to produce salt and water. CuO + 2HCl → CuCl2 + H2O Oxides of non-metals are acidic as they react with bases to produce salt and water. CO2 + Ca(OH)2 → CaCO3 + H2O Question 7. Write a balanced chemical eauatin for the renction between sodium carbonals and hydrochloric acid indicating the physical state of reactions and the products. Answer: The balanced equation for the reaction between sodium carbonate and hydrochloric acid is given below: Na2CO3(s) + 2HCl(aq) → 2NaCl(aq) + H2O(l) + CO2(g) Question 8. Give reasons for the following: (A) Only one half of water molecule is shown in the formula of Plaster of Paris. (B) Sodium hydrogen carbonates is used as an antacid. (C) On strong heating, blue coloured copper sulphate crystals turn white. Answer: Question 9. A student prepared solutions of (I) an acid and (II) a base in two separate beakers. She forgot to label the solutions and litmus paper is not available in the laboratory. Since, both the solutions are colourless, how will she distinguish between the two? Answer: In the absence of litmus, other natural or synthetic substances can be used to test acid and bases. Such substances are called indicators. Indicators such as methyl orange and phenolphthalein can be used to test the nature of a solution. These indicators show change in their colour in acidic, neutral and basic solutions. We can also use natural indicators such as turmeric and grape juice. A few indicators with characteristic colour change are shown below: Question 10. Fill in the missing data in the given table. Answer: 1. Acid: HCl NH4OH + HCl → NH4Cl + H2O 2. Formula: CuSO4 and base: Cu(OH)2 H2SO4 + Cu(OH)2 → CuSO4 + 2H2O 3. Acid: HCl NaOH + HCl → NaCl + H2O 4. Base: Mg(OH)2 Mg(OH)2 + 2HNO3 → Mg(NO3)2 + 2H2O 5. Base: KOH and Acid: H2SO4 2KOH + H2SO4 → K2SO4 + 2H2O 6. Acid: HNO3 Ca(OH)2 + 2HNO3 → Ca(NO3)2 + 2H2O Question 11. How is washing soda prepared from sodium carbonate? Give its chemical equation. State the type of this salt. Name the type of hardness of water that can be removed by it? Answer: Question 12. (A) You are given two solutions A and B and their pH is 6 and 8 respectively. Answer the following: (i) Which of the two solutions have more hydrogen ion concentration? (ii) Which is acidic and which is basic? Answer: pH of solution A = 6 pH of solution B = 8 (i) Solution A will have a higher hydrogen ion concentration. Explanation: We know that the pH of any solution is inversely proportional to the hydrogen ion concentration. This means that the solution that has lower pH number will have the higher hydrogen ion concentration. (ii) Also solution A is acidic and solution B is basic because H+ ion concentration is higher in acidic solution. (B) What is dilution? Answer: Mixing an acid or base with water results in decrease in concentration of ions (H3O+/ OH) per unit volume. Such process is called dilution and the acid or base is said to be dituted. The process of dissolving an acid or a base in water is a highly exothermic reaction. Question 13. Equal lengths of magnesium ribbons are taken in test tubes A and B. Hydrochloric acid (HCl) is added to test tube A, while acetic acid (CH3COOH) is added to test tube B. In which test tube will the fizzing occur more vigorously and why? Answer: Question 14. Crystals of a substance changes their color on heating in a closed vessel but regained it after sometime, when they were allowed to cool down. (A) Name one such substance. Answer: One such substance whose crystals changes its colour from blue to white on heating in a closed vessel for some time is hydrated copper sulphate, CuSO4.5H2O. (B) Explaain the phenomenon involved. Answer: Hydrated salts contain molecules of water known as water of crystallization. When such crystals are heated in a closed container, they lose their water of crystallization and hence change of colour is observed. Related Theory: When a salt which has lost its water of crystallization due to heating is left to cool down, it absorbs moisture from air and regains its water of crystallisation and thus, also its color. Question 15. The pH of the mouth of a person is lower than 5.5. What changes will occur in EMB his mouth? How these changes can be controlled? Write any two measures. Answer: When the pH of the mouth of a person is lower than 5.5, the acid produced by the action of bacteria on sugar and food particles in mouth corrodes even the tooth enamel which is made up of calcium phosphate. This leads to dental caries and tooth decay. These changes can be controlled by the following measures: 1. By using tooth pastes, which are generally basic in nature, as they can neutralize the excess acid produced in the mouth and hence help in preventing tooth decay. 2. By regular brushing of teeth twice a day and especially after eating sweets and chocolates. #### MCQ Questions for Class 10 Science with Answers ## Online Education MCQ Questions for Class 10 Economics Chapter 4 Globalisation and the Indian Economy with Answers Students can also read Online Education MCQ Questions for Class 10 Economics Chapter 4 Globalisation and the Indian Economy Questions with Answers hope will definitely help for your board exams. https://ncertmcq.com/tag/globalisation-and-the-indian-economy-class-10-mcqs-questions/ ## Online Education for Globalisation and the Indian Economy Class 10 MCQs Questions with Answers Class 10 Economics Chapter 4 MCQ With Answers Question 1. Which one of the following organisations lag stress on liberalisation of foreign trade and foreign investment? (a) International Monetary Fund (b) International Labour Organisation (c) World Health Organisation (d) World Trade Organisation Answer: (d) World Trade Organisation Explanation: The World Trade Organisation was created with an aim to regulate and monitor if appropriate rules were being implemented by the countries. Globalisation And The Indian Economy Class 10 MCQ Question 2. Choose the correctly matched pair: (a) Sundaram Fasteners – Indian MNC (b) Ranbaxy-Chinese MNC (c) Ford Motors-British MNC (d) Xiaomi-Korean MNC Answer: (a) Sundaram Fasteners-Indian MNC Explanation: Ranbaxy-Indian MNC Ford Motors-American MNC Xiaomi-Chinese MNC Globalisation Class 10 MCQ Question 3. Entry of MNCs in a domestic market may prove harmful for (a) Large scale producers (b) Domestic producers (c) Native Bankers (d) Exporters of goods Answer: (b) Domestic producers Explanation: The entry of MNC into the domestic market will prove fruitful to native bankers, large scale producers as they will be involved in the manufacturing and exporters as export will improve. The domestic producers alone will be harmed as it might close down their production. Globalisation MCQ Class 10 Question 4. Which one of the following has been major source of foreign investment in the IT industry? (a) Bharat Heavy Electricals Limited (b) Oil India Limited (c) Steel Authority of India Limited (d) Business process outsourcing Answer: (d) Business process outsourcing Explanation: The other choices are all manufacturing units. Which among Mex, RCH2X, R2CHX , and R3CX is most reactive towards sn2 reaction​. Globalisation And The Indian Economy MCQ Question 5. Which one of the following types of countries has been more benefited from Globalisation? (a) Rich countries (b) Poor countries (c) Developing countries (d) Developed countries Answer: (c) Developing countries Explanation: Employment has been generated to the youth in many developing countries, which means better quality of living. MCQ On Globalisation Class 10 Question 6. Which one of the following Indian industries has been hit hard by globalisation? (a) IT (b) Toy making (c) Jute (d) Cement Answer: (b) Toy making MCQ Of Globalisation Class 10 Question 7. Removing barriers on or restrictions set by the government is known as: (a) Globalisation (b) Privatisation (c) Nationalisation (d) Liberalisation Answer: (d) Liberalisation Globalization Class 10 MCQ Question 8. Ford Motors set up its first plant in India at (a) Kolkata (b) Mumbai (c) Chennai (d) Delhi Class 10 Globalisation MCQ Question 9. …………. has helped most in the spread of production of services. (a) Manufacturing Industry (b) Automobile Sector (c) Call centres (d) IT Sector Answer: (d) IT Sector Globalisation Refers To MCQ Question 10. “MNCs keep in mind certain factors before setting up production”. What of the following statements is wrong when that assertion is concerned? (a) MNCs keep the availability of cheap skilled and unskilled labour in mind. (b) Proximity to markets is another important factor when MNCs are established. (c) Presence of a large number of local competitors also changes the opinions of people while establishing an MNC. (d) Favourable government policies are important for establishment of an MNC. Answer: (c) Presence of a large number of local competitors also changes the opinions of people while establishing an MNC. Explanation: MNCs are not interested in the local competitors as most of their products are for the export market. Globalization Refers To MCQ Question 11. …………… have led to a huge reduction in port handling costs and increased the speed with which exports can reach markets. (a) Containers (b) Airports (c) Vessels with Stands (d) Ships Answer: (a) Containers Globalization MCQs Class 10 Question 12. Cheaper imports, inadequate investment in domestic infrastructure might lead to (a) the slowdown in the agricultural sector (b) the slowdown in demands of domestic goods in the country (c) the slowdown in the industrial sector (d) slowdown in services Answer: (b) the slowdown in demands of domestic goods in the country MCQ Of Globalisation And Indian Economy Question 13. Which of the following country is NOT in the list of countries whom Ford Motors exporting its cars? (a) South Africa (b) Mexico (c) Brazil (d) All of these Answer: (d) All of these Explanation: Ford Motors, an American company, is one of the world’s largest automobile manufacturers with production spread over 26 countries of the world. Related Theory Ford Motors came to India in 1995, invested Rs.1700 crore to set up a plant near Chennai in collaboration with Mahindra and Mahindra, manufacturer of jeeps and trucks in India. MCQ Globalisation Class 10 Question 14. Which of the following company is the largest producer of edible oil in India? (a) Parakh Foods (b) Cargill Foods (c) Mahindra and Mahindra (d) None of the above Answer: (b) Cargill Foods Explanation: Cargill Foods is a very large American MNC, producing 5 million pouches of edible oil in India daily. Related Theory Cargill has bought over Parakh Foods which had built a large marketing network in various parts of India, also it had four oil refineries whose control has now shifted to Cargill. Class 10 Economics Chapter 4 MCQ Question 15. Which of the following statement is NOT correct about a multinational company? (a) It set up new factories for production. (b) It may buy existing local companies to expand its business. (c) It forms partnerships with local companies. (d) It does not have new technology and large huge money with it. Answer: (d) It does not have new technology and huge money with it. Globalization And The Indian Economy Class 10 MCQ Question 16. Which one of the following companies is NOT a multinational company? (a) Tata Motors (b) Reliance India Ltd. (c) Ranbaxy (d) Infosys Answer: (b) Reliance India Ltd. Explanation: Globalisation has enabled some large Indian companies to emerge as multinationals themselves. For example, Tata Motor (automobiles), Infosys (IT), Ranbaxy (medicines), Asian Paints (Paints), Sundaram Fasteners (nuts and bolts) are some Indian companies which are spreading their operations worldwide. Question 17. With what objective was World Trade Organisation set up? (a) To liberalise international trade (b) To allow free trade for all (c) To establish rules regarding international trade (d) All of these Answer: Question 18. Which of the following statement clearly defines what an MNC is? (a) A large company that owns or controls production in more than one nation. (b) A large company that owns or controls raw material for production. (c) A large company that deals in automobiles. (d) All of these. Answer: (a) A large company that owns or controls production in more than one nation. Question 19. The most common route for investments by MNCs in countries around the world is to: (a) set up new factories (b) buy existing local companies (c) form partnerships with local companies (d) none of these Answer: Question 20. Which of the following attributes are NOT determined by an MNC? (a) Price, Quality, delivery and raw material (b) Price, labour conditions, quality, delivery (c) Delivery and price only (d) Raw material and transport cost Answer: (b) Price, labour conditions, quality, delivery Question 21. Large MNCs in developed countries place orders for production with small producers which include: (a) Garments (b) Footwear (c) Sports (d) All of these Answer: (d) All of these Identify Question 22. Identify the following organization on basis of the hints given. (1) It was established with the aim to liberalise international trade. (2) 164 countries are its members. Answer: The World Trade Organisation Correct and Rewrite/ True-False State whether the following statements are True or False. If false, correct the statement. Question 23. The removal of barriers or restrictions by the government is known as globalisation. Answer: The removal of barriers or restrictions by the government is called liberalisation. Explanation: Liberalisation helps to remove all types of barriers to allow easy and affordable exchange of ideas, culture and even goods between countries. Related Theory Globalisation is the process of rapid integration or interconnection between countries by exchange of trade, ideas, culture, information and even markets. Question 24. International Monetary Fund (IMF) is an organisation whose aim is to liberalise international trade. [CBSE 2020,15] Answer: WTO is an organisation whose aim is to liberalise international trade. Explanation: World Trade Organisation (WTO) forms uniform rules and regulations to make trade simpler across the world. Related Theory International Monetary Fund was created to support economic stabilisation of Second World War economies. Nations were hurt and affected and hence needed funding and support to develop again. Uniform Distribution Calculator solves two basic tasks. Fill in the blanks with suitable information: Question 25. ………… results in connecting the markets or integration of markets in different countries. Answer: Foreign trade Explanation: ForeignTrade helps manufacturers to find markets in various countries. It results in tax on imports which governments can use to increase or decrease foreign trade and to decide what kind of goods and how much of each, should come into the country. Question 26. ………………… is the process of rapid integration or interconnection between countries. Answer: Globalisation Question 27. ………. refers to some restrictions including the tax on Imports which governments can use to increase or decrease foreign trade and to decide what kind of goods and how much of each, shouLd come into the country. Answer: Trade barrier Explanation: Indian government put barriers on foreign trad and foreign investment after independence to protect the producers within the country from foreign competition. Question 28. ………… is the freedom of markets and abolition of state imposed restrictions on the movement of goods. Answer: Liberalisation Question 29. ……….. is an international organisation whose aim is to liberalise international trade: (a) WTO (b) UNDP (c) World Bank (d) MNC Answer: Match the Columns Choose the correct pairs: Question 30. Match the following Indian companies from column A with the products these companies deal in from column B:  Column A (Indian Companies) Column B (Products these companies deal in) (a) Tata Motors (i) IT (b) Infosys (ii) Automobiles (c) Ranbaxy (iii) Paints (d) Asian Paints (iv) Medicines Answer:  Column A (Indian Companies) Column B (Products these companies deal in) (a) Tata Motors (ii) Automobiles (b) Infosys (i) IT (c) Ranbaxy (iv) Medicines (d) Asian Paints (iii) Paints Explanation: Globalisation has enabled these large Indian companies to emerge as MNCs. Another company that has become an MNC is Sundaram Fasteners which deals in nuts and bolts. Question 31. Match the following key terms given in column A with their meanings in column B:  Column A (Key Terms) Column B (Meanings) (a) Globalisation (i) Investment by multinationals (b) Liberalisation (ii) Controlling foreign trade (c) Tax barrier (iii) Integration between economies (d) Foreign investment (iv) Removing trade barriers Answer: ### Assertion Reasoning questions Class 10 Economics Chapter 4 In each of the following questions, a statemant of Assertion (A) is given followed by a corresponding statement of Reason (R). Select the correct answer to codes (a), (b) (c) or (d) as given below: (a) Both (A) and (R) are true and (R) is the correct explanation of (A). (b) Both (A) and (R) are true but (R) is not the correct explanation of (A). (c) (A) is correct but (R) is wrong. (d) (A) is wrong but (R) is correct. Question 32. Assertion (A): People also can play an important role in the struggle for fair globalisation. Reason (R): Governments have done exceptionally well in implementing the rules of WTO. Answer: (c) (A) is correct but (R) is wrong. Explanation: Massive campaigns and representation by people’s organisations have influenced important decisions relating to trade and investments at the WTO. Question 33. Assertion (A): Not everyone has benefited from Globalisation equally. Reason (R): People with education, skill and wealth have made the best use of the new opportunities while others have not been able to make the best use of it. Answer: (a) Both (A) and (R) are true and (R) is the correct explanation of (A). Question 34. Assertion (A): Several of the top Indian companies have been able to benefit from the increased competition. Reason (R): They have been able to get more customers using the existing technology. Answer: (c) (A) is correct but (R) is wrong. Explanation: Greater competition has forced the companies to invest in newer technologies and more infrastructure, along with better quality products which has helped these companies to gain a better consumer base with help from the competition. Question 35. Assertion (A): Foreign companies are demanding more rigidity in labour laws. Reason (R): Flexible Labour laws give better chances for companies to profit. Answer: (Competency Based Questions (CBQs)) Question 1. Read the given source and answer the question that follows: Mr. Samson buys a company and then proceeds to buy new machines and furniture for the new company. He buys all his new employees clothes or new uniforms. He buys them new computers and redecorates the entire office. Which one of the following statements is correct considering the source? (a) Mr Samson loaned the money to this new office. (b) Mr Samson spent money on social customs. (c) Mr Samson invested this money because he bought the furniture, uniforms and machines. (d) Mr Samson traded this money. Answer: (c) Mr Samson invested this money because he bought the furniture, uniforms and machines. Question 2. Read the given source and answer the question that follows: A news magazine published for London readers is to be designed and printed in Delhi. The text of the magazine is sent through the Internet to the Delhi office. The designers in the Delhi office get orders on how to design the magazine from the office in London using telecommunication facilities. Which of the following phenomena helps these companies to execute these activities? (a) Foreign Trade (b) Domestic Trade (c) Globalisation (d) Investment Answer: Question 3. Choose the correct statement about factors of globalisation in India: (I) Improvement in transportation techno¬logy. (II) Liberalisation of foreign trade and foreign investment. (III) Favourable rules of World Trade Organisation towards India in comparison to developed countries. Choose the correct options from the codes given below: (a) Only (I) and (II) (b) Only (I) and (III) (c) Only (II) and (III) (d) Only (III) Answer: (a) Only (I) and (II) Explanation: WTO is supposed to allow free trade for all. However, in practice, it is seen that developed countries have retained trade barriers unfairly. On the other hand, WTO rules have forced developing countries to remove trade barriers. It is not partial in favour of India because it is an international organisation initiated by developed countries. Question 4. Read the given source and answer the question that follows: The above evidence indicates that not everyone has benefited from gLobaiisation. People with education, skill and wealth have made the best use of the new opportunities. On the other hand, there are many people who have not shared the benefits. Since globalisation is now a reality, the question is how to make globalisation more ‘fair’? Fair globalisation would create opportunities for all, and also ensure that the benefits of globalisation are shared better. Identify which of the following statements is not true about Globalization. (a) Globalisation is the process of rapid integration between countries. (b) It is movement of more and more investments and technology between countries. (c) Globalisation is introduction of restrictions or barriers by the government. (d) It is movement of more and more goods and services between countries. Answer: (c) Globalisation is introduction of restrictions or barriers by the government. Explanation: Globalisation is the process of rapid integration or interconnection between the countries. Through Globalisation more and more goods, services, greater foreign investments, technology and movement of people are taking place between countries. Globalisation doesn’t call for restrictions or barriers. It rather brings the countries in closer contact with each other. Question 5. Read the source given below and answer the questions that follow: Ford Motors, an American company, is one of the world’s largest automobile manufacturers with production spread over 26 countries of the world. Ford Motors came to India in 1995 and spent Bs. 1700 crore to set up a large plant near Chennai. This was done in collaboration with Mahindra and Mahindra, a major Indian manufacturer of jeeps and trucks. By the year 2017, Ford Motors was selling 88,000 cars in the Indian markets, while another 1,81,000 cars were exported from India to South Africa, Mexico, Brazil and the United States of America. The company wants to develop Ford India as a component supplying base for its other plants across the globe. Answer the following MCQs by choosing the most appropriate option: (A) Fill in the blank with an appropriate option: Ford Motors is a Company. (a) Uni-national (b) Bi-national (c) Regional (d) Multi-national Answer: (d) Multi-national Explanation: Its production units are present in various countries and hence it is a MNC. (B) Which of the following local companies did Ford Motors collaborate with? (a) Hero motors (b) Honda and Suzuki (c) Mahindra and Mahindra (d) Volkswagen Answer: (C) Which of the following benefits are availed by the local company on collaborating with Ford Motors? (a) The demand for cars from local companies in India rises. (b) Ford Motors supplies new technology to the local company. (c) Ford Motors takes over the local company. (d) Ford Motors changes the management of local companies. Answer: (b) Ford Motors suppiies new technology to the local companies. (D) Which of the following statements best describe the benefit to Indian producers in this statement in simple words? “By the year 2017, Ford Motors was selling 88,000 cars in the Indian markets, while another 1,81,000 cars were exported from india.” (a) The demand of products after the joint collaboration has decreased. (b) The demand of products after the joint collaboration has increased. (c) The demand of products after the joint collaboration has remained the same. (d) The demand of products after the joint collaboration has completely shifted. Answer: (b) The demand of products after the joint collaboration has increased. Question 6. Read the source given below and answer the questions that follow: Even more remarkable have been the developments in information and communication technology. In recent times, technology in the areas of telecommunications, computers, and the Internet has been changing rapidly. Telecommunication facilities (telegraph, telephone including mobile phones, fax) are used to contact one another around the world, to access information instantly, and to communicate from remote areas. This has been facilitated by satellite communication devices. As you would be aware, computers have now entered almost every field of activity. You might have also ventured into the amazing world of the internet, where you can obtain and share information on almost anything you want to know. The Internet also allows us to send instant electronic mail (e-mail) and talk (voice-mail) across the world at negligible costs. Answer the following MCQs by choosing the most appropriate option: (A) Which of the following factors have experienced a change due to the Internet? (a) All the information in the world can be accessed at the click of a finger. (b) One can fly from one country to another. (c) One can establish a telephonic contact between a man in India and Alaska. (d) One can cook by watching a show on TV. Answer: (B) Which of the following ways has the IT sector helped in? (a) In production of goods (b) In production of services (c) In export of goods (d) In export of services Answer: (b) In production of services Explanation: Information and communication technology (or IT in short) has played a major role in spreading out production of services like Banking, teaching, hospitality across countries. (C) Fill in the blank with an appropriate option: …………………. is not a Telecommunication facility? (a) Telegraph (b) Mobiles (c) Emails (d) A cars Answer: (d) A Car Explanation: It is a transportation facility. (D) Complete the following: Boating- Development in transportation facilities; E- Banking (a) Development in Transport (b) Development in Trade (c) Development in Production (d) Development in IT Answer: Question 7. Read the source given below and answer the questions that follow: Having assured themselves of these conditions, MNCs set up factories and offices for production. The money that is spent to buy assets such as land, building, machines and other equipment is called investment. Investment made by MNCs is called foreign investment. Any investment is made with the hope that these assets will earn profits. At times, MNCs set up production jointly with some of the local companies of these countries. The benefit to the local company of such joint production is two-fold. First, MNCs can provide money for additional investments, like buying new machines for faster production. Second, MNCs might bring with them the latest technology for production. Answer the following MCQs by choosing the most appropriate option: (A) Statements are given below. Find the correct ones which suit the statement given in the questions. Investment means spending on: (I) factories and industrial building (II) machines (III) equipments (IV) gold ornaments for employees (V) Uniforms (VI) Vehicles for the company (a) (I) & (IV) (b) (I) & (III) (c) (II), (III) & (IV) (d) (I), (II), (III), (V) & (VI) Answer: (d) (I), (II), (III), (V) & (VI) (B) FDI (Foreign Direct Investment) attracted by Globalisation in India comes from the: (a) World Bank (b) Multinational companies (c) foreign governments (d) Indian residents Answer: (b) Multinational companies (C) How does Joint Production with Zara help a local company called Style Quotient? (a) It brings better technology and production methods to Style Quotient. (b) Zara gets a new manager. (c) Style Quotient gets a better transport vehicle. (d) Employees at Style Quotient get discounts at Zara Store. Answer: (a) It brings better technology and production methods to Style Quotient. (D) Which one of the following is a major benefit (to the MNC) of joint production between a local company and a Multinational Company? (a) MNC are able to earn more customers. (b) MNC can control the increase in the price of a good. (c) MNC can expand its office physically. (d) MNC can promote the local company. Answer: (a) MNC are able to earn more customers Question 8. Read the source given below and answer the questions that follow: 35-year old Sushila has spent many years as a worker in the garment export industry of Delhi. She was employed as a ‘permanent worker’ entitled to health insurance, provident fund, overtime at a double rate, when Sushila’s factory closed in the late 1990s. After searching for a job for six months, she finally got a job 30 km away from where she lives. Even after working in this factory for Several years, she is a temporary worker and earns less than half of what she was earning earlier. Sushila leaves her house every morning, seven days a week at 7:30 a.m. and returns at 10 p.m. A day off from work means no wage. She has none of the benefits she used to get earlier. Factories closer to her home have widely fluctuating orders and therefore pay even less. Answer the following MCQs by choosing the most appropriate option: (A) Has Globalisation been favourable to Sushila and other workers like her? (a) Yes, there are new jobs (b) No, there is greater unemployment because people now employ workers on a seasonal basis. (c) There is no change in employment opportunities. (d) Workers are not affected by Globalisation. Answer: (b) No, there is greater unemployment because people now employ workers on a seasonal basis. (B) Fill in the blank with an appropriate option: Globalisation so far has been more in favour of (a) Developed countries (b) Underdeveloped countries (c) Poor countries (d) It has had an equal effect. Answer: (a) Developed countries Explanation: They have been able to expand their markets and their consumer bases. (C) Which one of the following has benefited least because of globalisation in India? (a) Industrial Sector (b) Agriculture Sector (c) Service Sector (d) IT Sector Answer: (b) Agriculture Sector (D) Which of the following statements are not true about Sushila’s employment terms? (a) She gets more benefits like Medical leave due to Globalisation. (b) She has to work longer than usual. (c) Her wages have doubled. (d) She had received a promotion Answer: (a) She gets more benefits like Medical leave due to Globalisation. Explanation: all her existing terms have been cancelled and now she has no extra benefits. Question 9. Read the sources given below and answer the questions that follow: [CBSE 2020,14] Source A – Production across countries Until the middle of the twentieth century, production was largely organised within countries. What crossed the boundaries of these countries were raw material, food stuff and finished products. Colonies such as India exported raw materials and food stuff and imported finished goods. Trade was the main channel connecting distant countries. This was before large companies called multinational corporations (MNCs) emerged on the scene. Source B – Foreign trade and integration of markets Foreign trade creates an opportunity for the producers to reach beyond the domestic markets, i.e., markets of their own countries. Producers can sell their produce not only in markets located within the country but can also compete in markets located in other countries of the world. Similarly, for the buyers, import of goods produced in another country is one way of expanding the choice of goods beyond what is domestically produced. Source C – Impact of globalisation in India Globalisation and greater competition among producers – both local and foreign producers – has been of advantage to consumers, particularly the well-off sections in the urban areas. There is greater choice before these consumers who now enjoy improved quality and lower prices for several products. As a result, these people today, enjoy much higher standards of living than was possible earlier. Source A – Production across countries (A) How are MNCs a major force in connecting the countries of the world? Source B – Foreign trade and integration of markets Answer: MNCs act as a major force in connecting various countries of the world. They interact with Local producers in various counties across the globe to expand their production and markets which results in connection of widely dispersed locations on countries. (B) How does foreign trade become a main channel in connecting countries? Source C – Impact of globalisation in India Answer: Foreign trade helps to integrate various markets with one another through the means of domestic and international producers who sells the same product in domestic and international markets. The markets of all countries garner similar products and are integrated together. (C) How is globalisation beneficial for consumers? Answer: Globalisation is beneficial for consumers in the following ways: 1. High quality goods are available at lower prices. 2. A wide range of choice is available for the consumers. Question 10. Read the sources given below and answer the questions related to them : Source A – Globalisation and the Indian economy An consumers in today’s world, some of us have a wide choice of goods and services before us. The latest models of digital cameras, mobile phones and televisions made by the leading manufacturers of the world are within our reach. Every season, new models of automobiles can be seen on Indian roads. Source B – Foreign trade and integration of markets Foreign trade creates an opportunity for the producers to reach beyond the domestic markets, i.e., markets of their own countries. Producers can sell their produce not only in markets located within the country but can also compete in markets located in other countries of the world. Similarly, for the buyers, the import of goods produced in another country is one way of expanding the choice of goods beyond what is domestically produced. Source C – The struggle for fair globalisation In the past few years, massive campaigns and representation by people’s organisations has influenced important decisions relating to trade and investments at the World Trade Organisation. This has demonstrated that people can also play an important role in the struggle for fair globalisation. Source A – Globalisation and the Indian economy (A) How is the impact of globalisation visible on consumers? Source B – Foreign trade and integration of markets Answer: (B) How does foreign trade integrate markets? Explain. Source C – The struggle for fair globalisation Answer: (C) How do people play an important role in the struggle for fair globalisation? Explain. Answer: Very Short Answer Type Questions Question 1. State any one example for a trade barrier? Answer: Taxes and Import duties Question 2. Why did the Indian government remove barriers to a large extent on foreign trade and foreign investment? Answer: They removed the trade barriers to help the native industries and boost their trade by letting the foreign competition in the country’s market. Question 3. What attracts the foreign investment? Answer: Question 4. Due to which reason the latest models of different items are available within our reach? Answer: Foreign Trade integrates different markets and helps the countries to make products from across the world available to their citizens. Question 5. Why are MNC setting them Customer Care Centres in India? Answer: India has a lot of educated youth who can speak English well and thereby are the perfect candidates to be customer care professionals. Question 6. Differentiate between multinational corporations and domestic companies. Answer: Multinational corporations operate in two or more countries while domestic companies restrict their operations to a single country. Related Theory: Multinational companies move to other countries and expand their business for various reasons. They also give a tough competition to domestic companies. Question 7. What is the basic function of foreign trade? Answer: Question 8. The MNC’s of a country sets up a production jointly with the local company of other country. State any one benefit of this joint production to the local company. Answer: Benefits of Joint Production: 1. MNC can provide money for additional investment. 2. MNC might bring latest technology for production, (any 1 to be mentioned) Question 9. Distinguish between investment and foreign investment. Answer: When land, assets or buildings are purchased and kept hold of, they are considered as investments, whereas when multinational corporations (MNC’s) invest money or finances in a project of another company in another country, it is considered as foreign investment. Question 10. Due to which reason are the latest models of different items available within our reach? Answer: The latest models of different items are available within our reach due to ‘globalisation. Question 11. Define globalisation. Answer: Globalisation is defined as the integration between different countries through foreign trade and foreign investments by various muLti-national corporations (MNCs). Related Theory: Globalisation has helped a lot in interlinking economies and markets across the world. Now, people are able to sell their produce in the foreign markets also. Question 12. Where do MNCs prefer to set up their offices and factories? Answer: MNCs set up offices and factories for production in regions where they can get cheap labour and other resources. Explanation: Every MNC wants to attain maximum profit off their business. One of the easiest way to do is to reduce the cost of production by either updating the infrastructure, to include better tecnnology, or by employing cheap labour, finding cheaper sources of energy to be used. Question 13. How has globalisation enabled the national companies to emerge as Multinational Companies (MNCs)? Answer: Globalisation enabled the national companies to emerge as MNCs: New opportunities have been provided to the companies/ Helped in collaboration with foreign companies/ Technological and production inputs. Question 14. Which is the most common route for investment by MNCs in countries around the world? Answer: The easiest way for MNCs is to invest around the world is to buy up local companies and then to expand production by controlling the means. Question 15. Define the term Liberalisation. Answer: Liberalisation refers to the removal or partial or complete loosening of the restrictions set by the government on foreign investment and trade. It also eases up the process of import and export. Question 16. Name some Indian companies which are now emerging as Multi National Corporations. Answer: Tata motors, Infosys, Ranbaxy, Asian paints and Sundaram fasteners are some Indian companies which are spreading their operations worldwide. Explanation: MNCs or Multi National Corporations are companies which are based in various countries and their market and production are both expanded across various countries and continents. Question 17. Define the term ‘investment’. Answer: The money that is spent to buy assets such as land, building, machines and other equipment is called investment. Explanation: Any investment is made with the hope that these assets will earn profits. Related Theory: Investment made by MNCs is called foreign investment. Question 18. Read the given source and answer the question that follows: Answer: In recent years, the central and state governments in India are taking special steps to attract foreign companies to invest in India. Companies who set up production units in the SEZs do not have to pay taxes for an initial period of five years. Question 19. What are SEZs? Answer: SEZs are Special Economic Zones or Industrial Zones set up to attract foreign investment by government of India. Related Theory: SEZs have world class infrastructural facilities and other facilities like tax rebates, flexibility in labour laws to attract investors. #### MCQ Questions for Class 10 Social Science with Answers ## Online Education MCQ Questions for Class 11 Physics Chapter 9 Mechanical Properties of Solids with Answers Check the below Online Education NCERT MCQ Questions for Class 11 Physics Chapter 9 Mechanical Properties of Solids with Answers Pdf free download. MCQ Questions for Class 11 Physics with Answers were prepared based on the latest exam pattern. We have provided Mechanical Properties of Solids Class 11 Physics MCQs Questions with Answers to help students understand the concept very well. ## Online Education for Mechanical Properties of Solids Class 11 MCQs Questions with Answers Mechanical Properties Of Solids MCQ Question 1. A body of mass 1 kg is attached to one end of a wire and rotated in horizontal circle of diameter 40 cm with a constant speed of 2 m/s. what is the area of cross-section of the wire if the stress developed in the wire is 5 × 106 N/m²? (a) 2 mm² (b) 3 mm² (c) 4 mm² (d) 5 mm² Answer Answer: (c) 4 mm² Mechanical Properties Of Solids Class 11 MCQ Question 2. In a wire, when elongation is 2 cm energy stored is E. if it is stretched by 10 cm, then the energy stored will be (a) E (b) 2 E (c) 4 E (d) 25 E Answer Answer: (d) 25 E MCQ On Mechanical Properties Of Solids Question 3. Two wires A and B are of the same length. The diameters are in the ratio 1 : 2 and the Youngs modulus are in ratio 2 : 1. if they are pulled by the same force, then their elongations will be in ratio (a) 4 : 1 (b) 1 : 4 (c) 1 : 2 (d) 2 : 1 Answer Answer: (d) 2 : 1 Mechanical Properties Of Solids MCQ Pdf Question 4. Hookes law essentially defines (a) Stress (b) Strain (c) Yield point (d) Elastic limit Answer Answer: (d) Elastic limit MCQ On Mechanical Properties Of Solids Class 11 Question 5. Longitudinal strain is possible in the case of (a) Gases (b) Liquid (c) Only solids (d) Only gases & liquids Answer Answer: (c) Only solids Engineering Physics MCQ Electrical Engineering. Class 11 Physics Chapter 9 MCQ Question 6. Two wires have the same material and length, but their masses are in the ration of 4 : 3. If they are stretched by the same force, their elongations will be in the ratio of (a) 2 : 3 (b) 3 : 4 (c) 4 : 3 (d) 9 : 16 Answer Answer: (b) 3 : 4 Mechanical Properties Of Solid MCQ Question 7. A rubber cord of cross sectional area 1 mm² and unstretched length 10 cm is stretched to 12 cm and then released to project a stone of mass 5 gram. If Y for rubber = 5 ? 108N/m², then the tension in the rubber cord is (a) 25 N (b) 50 N (c) 100 N (d) 200 N Answer Answer: (c) 100 N MCQ Questions On Mechanical Properties Of Solids Question 8. Out of the following materials, whose elasticity is independent of temperature? (a) Copper (b) Invar steel (c) Brass (d) Silver Answer Answer: (b) Invar steel MCQs On Mechanical Properties Of Solids Question 9. An iron bar of length l m and cross section A m² is pulled by a force of F Newton from both ends so as to produce and elongation in meters. Which of the following statement statements is correct (a) Elongation is inversely proportional to length l (b) Elongation is directly proportional to cross section A (c) Elongation is inversely proportional to A (d) Elongation is directly proportional to Youngs modulus Answer Answer: (c) Elongation is inversely proportional to A Mechanical Properties Of Solids MCQs Question 10. The ratio of the change in dimension at right angles to the applied force to the initial dimension is known as (a) Youngs modulus (b) Poissons ratio (c) Lateral strain (d) Shearing strain Answer Answer: (c) Lateral strain Class 11 Physics Chapter 9 MCQs Question 11. Four wires whose lengths and diameter respectively are given below are made of the same material. Which of these will have the largest extension when same tension is applied? (a) 0.50 m, 0.50 mm (b) 1.00 mm, 1.00 mm (c) 2.00 m, 2.00 mm (d) 4.00 m, 4.00 mm Answer Answer: (a) 0.50 m, 0.50 mm MCQ On Elasticity Class 11 Question 12. When the intermolecular distance increases due to tensile force, then (a) There is no force between the molecules (b) There is a repulsive force between the molecules (c) There is an attractive force between the molecules (d) There is zero resultant force between the molecules Answer Answer: (c) There is an attractive force between the molecules Class 11 Mechanical Properties Of Solids MCQ Question 13. A body of mass 1 kg is attached to one end of a wire and rotated in horizontal circle of diameter 40 cm with a constant speed of 2 m/s. what is the area of cross-section of the wire if the stress developed in the wire is 5 × 106 N/m²? (a) 2 mm² (b) 3 mm² (c) 4 mm² (d) 5 mm² Answer Answer: (c) 4 mm² MCQ Of Mechanical Properties Of Solids Question 14. One end of a steel wire of area of cross-section 3 mm² is attached to the ceiling of an elevator moving up with an acceleration of 2.2 m/s². if a load of 8 kg is attached at its free end, then the stress developed in the wire will be (a) 8 × 106 N/m² (b) 16 × 106 N/m² (c) 20 × 106 N/m² (d) 32 × 106 N/m² Answer Answer: (d) 32 × 106 N/m² Class 11 Physics Mechanical Properties Of Solids MCQs Question 15. The ratio of the change in dimension at right angles to the applied force to the initial dimension is known as (a) Youngs modulus (b) Poissons ratio (c) Lateral strain (d) Shearing strain Answer Answer: (c) Lateral strain MCQ Questions For Class 11 Physics Chapter 9 Question 16. The magnitude of the force developed by raising the temperature from 0°C to 100°C of the iron bar of 1.00 m long and 1 cm² cross-section when it is held so that it is not permitted to expand or bend is (a = 10-5/oC and Y = 1011 N/m²) (a) 103 N (b) 104 N (c) 105 (d) 109 N Answer Answer: (b) 104 N Chapter 9 Physics Class 11 MCQs Question 17. The upper end of wire 1 m long and 2 mm radius is clamped. The lower end is twisted through an angle of 45°. The angle of shear is (a) 0.09° (b) 0.9° (c) 9° (d) 90° Answer Answer: (a) 0.09° Mechanical Properties Of Solids MCQ Questions Question 18. The radii of two wires of a same material are in ratio 2 : 1. if the wires are stretched by equal forces, the stress produced in them will be (a) 2 : 1 (b) 4 : 1 (c) 1 : 4 (d) 1 : 2 Answer Answer: (c) 1 : 4 Class 11 Physics Mechanical Properties Of Solids MCQ Question 19. A rubber cord of cross sectional area 1 mm² and unstretched length 10 cm is stretched to 12 cm and then released to project a stone of mass 5 gram. If Y for rubber = 5 ? 108N/m², then the tension in the rubber cord is (a) 25 N (b) 50 N (c) 100 N (d) 200 N Answer Answer: (c) 100 N Class 11 Physics Ch 9 MCQ Question 20. In a wire, when elongation is 2 cm energy stored is E. if it is stretched by 10 cm, then the energy stored will be (a) E (b) 2 E (c) 4 E (d) 25 E Answer Answer: (d) 25 E We hope the given NCERT MCQ Questions for Class 11 Physics Chapter 9 Mechanical Properties of Solids with Answers Pdf free download will help you. If you have any queries regarding CBSE Class 11 Physics Mechanical Properties of Solids MCQs Multiple Choice Questions with Answers, drop a comment below and we will get back to you soon. ## MCQ Questions for Class 10 Economics Chapter 1 Development with Answers Students can also read Online Education MCQ Questions for Class 10 Economics Chapter 1 Development Questions with Answers hope will definitely help for your board exams. https://ncertmcq.com/mcq-questions-for-class-10-social-science-with-answers/ ## Online Education for Development Class 10 MCQs Questions with Answers Development Class 10 MCQ Question 1. The Literacy rate of Kerala in 2011 was ………………………. (a) 82 (b) 94 (c) 62 (d) 50 Answer: (b) 94 Class 10 Economics Chapter 1 MCQ With Answers Question 2. Fill in the bLank with respect to the correct criterion of comparison by choosing the most appropriate option: Students – Height and Weight; Countries – ……………………. (o) Number of Cities (b) Size of the Territory (c) Per Capita Income (d) Population Answer: (c) Per Capita Income Class 10 Development MCQ Question 3. In which state of India is the infant mortality rate highest? (a) Goa (b) Bihar (c) Uttar Pradesh (d) Kerala Answer: (b) Bihar Development MCQ Class 10 Question 4. Which one of the following actions enhances environmental degradation? (a) Planting of trees along the roadsides. (b) Prevention of sewage disposal into water bodies (c) Ban on use of plastic bags. (d) Allowing the level of exhaust fumes emitted by cars, buses, trucks, etc., to rise. Answer: Class 10 Economics Chapter 1 MCQ Question 5. Per capita income is: (a) Income per State (b) Income per Earning and Non-Earning Members of a family (c) Income of each female in a house (d) Income per person Answer: (d) Income per person MCQ Of Development Class 10 Question 6. What will be the top priority in the developmental goal of jobless youth? (a) More employment opportunities (b) More days of work and better wages (c) Metal roads for transportation (d) Establishment of a high school Answer: (a) More employment opportunities Class 10 Economics Chapter 1 Development MCQ Online Test Question 7. Which one of the following is not a feature of an underdeveloped country? (a) Agriculture as the major occupation (b) High technological development (c) Mass poverty (d) Mass illiteracy Answer: (b) High technological development Explanation: Any underdeveloped country does not have access to high technology because of its economic inadequacy. Economics Class 10 Chapter 1 MCQ Question 8. ……………… will be the aspiration of a working woman. (a) To have a garden (b) To have a safe and secure work environment at the office. (c) To have good job opportunities where her education can be made use of. (d) To have better technologies that can make data storing easy. Answer: (b) To have a safe and secure work environment at the office. MCQ On Development Class 10 Question 9. For each of the sectors, that we come across we should focus on employment and: (a) GDP (b) GNP (c) NNP (d) NI Answer: (a) GDP Explanation: The other quantities have been associated with the nation and not with individual sectors. Economics Chapter 1 Class 10 MCQ Question 10. Which of the following factors are important for development other than income? [Diksha] (a) Per Capita Income (b) Literacy (c) Net Attendance Ratio (d) All of the above Answer: Class 10 Economics Chapter 1 Development MCQ With Answers Question 11. Which of the following neighboring country of India has a higher HDI rank than India? (a) Sri Lanka (b) Nepal (c) Pakistan (d) None of the above Answer: (a) Sri Lanka MCQ Development Class 10 Question 12. Which of the following states has the highest literacy rate according to 2018 study reports? (a) Haryana (b) Bihar (c) Punjab (d) Kerala Answer: (d) Kerala Get UML full form and full name in details. Class 10 Economics Chapter 1 One Word Questions And Answers Question 13. What is the full form of PDS? (a) Public Distribution System (b) Public Development System (c) Public Division System (d) Public discussion System Answer: (a) Public Distribution System Explanation: Public Distribution System is a scheme run by the government to provide essential food grains like rice, wheat, pulses, oil at very affordable to the disadvantaged classes to ensure their healthy development. MCQ Questions For Class 10 Economics Chapter 1 Question 14. …………. is an example of a renewable resource. (a) Petroleum (b) Crude oil (c) Groundwater (d) Coal resources Answer: (c) Groundwater Explanation: Groundwater is a renewable resource and can be renewed through natural processes. Other renewable resources are Solar Energy, wind energy, etc. Non-Renewable Resources, once exhausted can not be renewed naturally. For example, Coal, minerals, and petroleum. Class 10 Eco Ch 1 MCQ Question 15. Literacy rate measures the proportion of the Literate population in the Age group: (a) Above 5 years (b) Above 12 years (c) Above 7 years (d) Above 6 years Answer: Question 16. The average income of a person is called: (a) Total income (b) Per capita income (c) Gross income (d) Per nation income Answer: (b) Per capita income Explanation: The average income of a person in a country is known as per capita income. It is calculated by dividing the total income of the country by its total population. Related Theory • The total income of a person is the sum of his income from all sources in a particular time period i.e. monthly or annually. • The value of the total goods and services produced within a country in a year is called the National income of a country. Full form of DSLR is Digital Single-lens Reflex Camera. Question 17. UNDP can be expanded as: (a) United Nations Development Programme (b) United Nations Diversity Playground (c) United Nations Democratic Programme (d) None of these Answer: (a) United Nations Development Programme Explanation: United Nations Development Programme is a United Nations Agency that studies, looks after the development of member countries by holding annual discussions and programs. It releases a human development report where it measures various countries on scale of a few of its indicators. Question 18. Based on Per capita income, India comes in the category of: (a) Middle-income group (b) Low-income group (c) High-income group (d) Low middle-income group Answer: Question 19. Which of the following statement defines Sustainable Development? (a) Sustainable use of natural resources without considering the need of the future generation. (b) Present generation fulfills its needs while considering the needs of the future generation as well. (c) It means utilization of natural resources by the past, present and future generation. (d) To meet the needs of the future generations even if the needs of the present generation go unmet. Answer: (A) Present generation fulfils its needs while considering the needs of the future generation as well. Identify Question 20. Identify the object on the basis of the hints given: (1) The resource is renewable. (2) Its overuse is found in the agriculturally prosperous regions of Punjab and Western U.P. Answer: Groundwater Correct and Rewrite Question 21. Rewrite the statement after correcting the underlined phrase. A country having a high standard of living and a better environment in terms of health and safety is known as a developing country. Answer: A country having a high standard of living and a better environment in terms of health and safety is known as a developed country. Fill in the Blanks Question 22. USA has low reserves of oil and secures it through ……………………… Answer: Economic power. Question 23. Observe the source given below and answer the question that follows: Complete the following sentence based on your observation. The idea of …………….. can be depicted from the cartoon. Question 24. ……………. is a new-renewable resource. Answer: Coal or Crude Oil Question 25. The present Levels of development are Answer: not sustainable Question 26. The number of deaths of children less than one year of age per 1000 live births is referred as …………. Answer: Infant mortality rate (IMR). Question 27. One of the best ways to reduce over-usage of groundwater is ………… Answer: Implementation of stringent policies to control misuse of water. Question 28. ……………… is an example of renewable resource. Answer: Groundwater Explanation: Renewable resource are replenished by nature as in the case of crops and plants. However even these resources may be overused. Groundwater is renewable but highly overused in states of Punjab, Haryana and Western UP. Question 29. Human Development Index (HDI) in India can be improved through ………………. Answer: (1) Provision of free educational facilities for children up to 16 years of age to improve literacy rate. (2) Provision of better and more robust health care services. (Mention any 1) Match the Columns Choose the correct pairs: Question 30. Choose the incorrect option from Column A and Column B.  Column A (Category of person) Column B (Developmental goats/Aspirations) (a) Landless rural Labourers (i) More days of work and better wages (b) Prosperous farmers from Punjab (ii) Availability of other sources of irrigation (c) Farmers who depend only on rain for growing crops (iii) Assured higher support prices for their crops (d) A rural woman from a Land- owning family (iv) Regular job and high wages to increase her income Answer: (c) Farmers who depend only on rain for growing crops (iii) Assured higher support prices for their crops. Explanation: A large amount of water is required for the cultivation of crops of the farmers, who are primarily dependent on rain. Hence, their primary need is the availability of irrigation facilities to support their crops in the absence of rain. Question 31. Match the countries given with their HDI Rank according to Human Development Report, UNDP, 2018.  Column A Column B (a) Sri Lanka (i) 150 (b) India (ii) 149 (c) Pakistan (iii) 130 (d) Nepal (iv) 76 Answer:  Column A Column B (a) Sri Lanka (iv) 76 (b) India (iii) 130 (c) Pakistan (i) 150 (d) Nepal (ii) 149 Explanation: Human Development Report published by UNDP annually compares countries based on the educational levels of the people their health status and per capita income. It calculates a cumulative score by measuring GNI. life expectancy at birth and mean years of schooling (literacy and accessibility to educational facilities). All member countries are compared and ranks are given according to their score. Higher rank means greater human development. Question 32. Choose the correctly matched option from the following:  Column I (Category of person) Column II (Development goat) (a) Farmers who depend only on rain for growing crops More days of work and better wages (b) Landless rural Labourers Higher support prices for their crops (c) Prosperous farmers from Punjab Regular wages (d) An adivosi from Narmada volley To fulfill Livelihood ### Assertion Reasoning questions Class 10 Economics Chapter 1 In each of the following questions, a statement of Assertion (A) is given followed by a corresponding statement of Reason (R). Select the correct answer to codes (a), (b) (c) or (d) as given below: (a) Both (A) and (R) are true and (R) is the correct explanation of (A). (b) Both (A) and (R) are true but (R) is not the correct explanation of (A). (c) (A) is correct but (R) is wrong. (d) (A) is wrong but (R) is correct. Question 33. Assertion (A): Increase in population, urbanization and industrialization lead to increased use for fossil fuels. Reason (R): Overuse of conventional energy resources has resulted in the phenomenon of greenhouse effect. Answer: (b) Both (A) and (R) are true but (R) is not the correct explanation of (A). Question 34. Assertion (A): Groundwater is under serious threat of overuse in many parts of the country. Reason (R): About 300 districts have reported a water level decline of over 4 meters during the past 20 years. Answer: (a) Both (A) and (R) are true and (R) is the correct explanation of (A). Question 35. Assertion (A): Development involves thinking about the ways in which we can work towards achieving goals of holistic growth. Reason (R): Holistic growth is economic growth. Answer: Question 36. Assertion (A): Kerala has a better net attendance ratio than Bihar. Reason (R): Kerala has less female children than Bihar hence the attendance ratio is better. Answer: (c) (A) is correct but (R) is wrong. Explanation: Kerala has better infrastructure and educational facilities for students. This makes it easier to attend school and study. Question 37. Assertion (A): People not only think of better income but also have goals such as security, respect for others, equal treatment, freedom, etc. in mind. Reason (R): Money cannot buy everything. Answer: (Competency Based Questions (CBQs)) Question 1. The given picture shows an overuse of which of the following resources? (a) Soil (b) Air (c) Woman Power (d) Groundwater Answer: (d) Groundwater Question 2. Read the given source and answer the question that follows: The idea of development or progress has always been with us. We have aspirations or desires about what we would like to do and how we would like to live. Similarly, we have ideas about what a country should be like. Which of the following is the right replacement for the underlined sentence? (a) We have community goals. (b) We have occupational goals. (c) We have developmental goals. (d) We have society goals. Answer: (c) We have developmental goals. Question 3. Match the items in Column A to that of Column B and choose the right option:  Column A Column B (A) Girl in an urban family (I) Regular wages and more job days (B) A minister (II) Equal opportunities just like her brother (C) A laborer (III) More profit, more projects (D) A businessman (IV) More votes (a) (A)-(II),(B)-(IV),(C)-(I),(D)-(III) (b) (A)-(III),(B)-(IV),(C)-(II),(D)-(I) (c) (A)-(III),(B)-(I),(C)-(IV),(D)-(II) (d) (A)-(I),(B)-(III),(C)-(II),(D)-(I) Answer: (a) (A)-(II),(B)-(IV),(C)-(I),(D)-(III) Question 4. Study the picture and answer the question that follows: What could be the development goal for the shown area? Answer: Question 5. Study the picture given below. Ident fy an appropriate developmental goal foe the characters. Answer: An appropriate developmental goal for the poor lady would be to have a stable job and affordable house for her small family. For the rich man, his developmental goal can be more opportunities for profit and investment from foreign countries, more luxurious Life or even a bigger car. Question 6. Study the table and answer the question tnat follows : Sources: Economic Survey, 2017-18 VoL 2, Government of India; National Sample Survey Organisation (Report No. 575) In comparison to Kerala, which state has the highest infant mortality rate ? Answer: Bihar Explanation: As Bihar lacks health and proper education facilities, the mortality rate is highest there. Question 7. Study the table and answer the question that follows: Which State has the lowest net attendance ratio at the secondary stage? Answer: Bihar Explanation: The table shows the lowest statistics for net attendance ratio in Bihar. Related Theory Net attendance ratio is the total number of children of age group 14 and 15 years attending school as a percentage of the total number of children in the same age group. Question 8. Based on the data given in the following table, calculate the average income for both countries: Which country has more equitable distribution of income? Answer: Question 9. Study the statistics in the table and answer the question that follows: Calculate the average income of the family. Answer: ₹10,000 Explanation: Average Income of the family: 7,000 + 8,000 + 10,000 + 15,000 = 40,000 Sum of incomes = 40,000 Answer: Question 10. Read the source given below and answer the questions that follow: A vessel dumped 500 tonnes of liquid toxic wastes into open-air dumps in a city and in the surrounding sea. This happened in a city called Abidjan in Ivory Coast, a country in Africa. The fumes from the highly toxic waste caused nausea, skin rashes, fainting, diarrhoea etc. After a month seven persons were dead, twenty in hospital and twenty six thousand treated for symptoms of poisoning. A multinational company dealing in petroleum and metals had contracted a local company of the Ivory Coast to dispose the toxic waste from its ship. (A) Which of the following would be an ideal goal for natives of Abidjan? (a) Free Healthcare, healthier environ-ment. (b) More space (c) More houses (d) More factories and hence more jobs Answer: (a) Free Healthcare, healthier environment. (B) Which of the following would be an ideal goal for the multinational company? (I) More money (II) To get rid of its waste without having to pay for its disposal. (III) More employees (IV) More profit (a) (I) only (b) (II) only (c) (III) only (d) (I) (II) & (IV) Answer: (C) Which resource was severely affected in the given source? Answer: Water in the sea bodies. (D) Assertion (A): Different people may have different and conflicting interests. Reason (R): They belong to different continents. (a) Both (A) and (R) are true and (R) is the correct explanation of (A). (b) Both (A) and (R) are true but (R) is not the correct explanation of (A). (c) (A) is correct but (R) is wrong. (d) (A) is wrong but (R) is correct. Question 11. Read the source given below and answer the questions that follow: Once it is realised that even though the level of income is important, yet it is an inadequate measure of the level of development, we begin to think of other criteria. There could be a long list of such criteria but then it would not be so useful. What we need is a small number of the most important things. Health and education indicators, such as the ones we used in comparison of Kerala and Haryana, are among them. Over the past decade or so, health and education indicators have come to be widely used along with income as a measure of development For instance, the Human Development Report published by UNDP compares countries based on the educational levels of the people, their health status and per capita income. It would be interesting to look at certain relevant data regarding India and its neighbours from the Human Development Report 2019. Answer the following MCQs by choosing the most appropriate option: (A) Which of the following countries has a better rank than India in Human Development Report for 2018? (a) Pakistan (b) Sri Lanka (c) Bangladesh (d) Nepal Answer: (b) Sri Lanka Explanation: Sri Lanka is at rank 76 while India is at rank 130. (B) Which of the following criteria is common in the assessment of development in the reports of the World Bank and UNDP? (a) Educational levels (b) Health Status (c) Gold Reserves (d) Per Capita Income Answer: (d) Per Capita Income (C) Where is the UNDP headquartered? (a) London (b) New York (c) Burns (d) Geneva Answer: (b) New York (D) Which of the Asian country is lower in HDI? (a) Myanmar (b) Pakistan (c) India (d) Bangladesh Answer: (b) Pakistan Explanation: Pakistan is at rank 150 according to the list of 2018. Question 12. Read the source given below and answer the questions that follow: Recent evidence suggests that the groundwater is under serious threat of overuse in many parts of the country. About 300 districts have reported a water level decline of over 4 metres during the past 20 years. Nearly one-third of the country is overusing their groundwater reserves. In another 25 years, 60 per cent of the country would be doing the same if the present way of using this resource continues. Groundwater overuse is particularly found in the agriculturally prosperous regions of Punjab and Western U.P., hard rock plateau areas of central and south India, some coastal areas and the rapidly growing urban settlements. Answer the following MCQs by choosing the most appropriate option: (A) Which of the following resources are renewable but excessively used? (a) Solar Energy (b) Wind Energy (c) Air (d) Trees Answer: (d) Trees Explanation: Trees are heavily deforested and uprooted for various industrial and construction projects. (B) What proportion of the country is over using their groundwater reserves? (a) One-Fourth (b) One-Third (c) One-Tenth (d) One-Eighth Answer: (b) One-Third (C) Which of the following options is a reason for Groundwater overuse? (I) Usage at homes (II) Usage at Agricultural sites (III) Watering plants (IV) Pollution through chemicals and solid wastes (V) Drinking (a) (I) only (b) (II) & (IV) (c) (III), (IV) & (V) (d) (I), (II) & (IV) Answer: (D) Which of the following is a solution to prevent Groundwater overuse? (a) Stop drinking groundwater (b) Stop irrigating plants and crops (c) Rainwater harvesting (d) Use river water for domestic usage Answer: (c) Rainwater harvesting Question 13. Read the source given below and answer the questions that follow: Do all of these persons have the same notion of development or progress? Most likely not. Each one of them seeks different things. They seek things that are most important for them, i.e., that which can fulfil their aspirations or desires. In fact, at times, two persons or groups of persons may seek things which are conflicting. A girl expects as much freedom and opportunity as her brother, and that he also shares in the household work. Her brother may not like this. Similarly, to get more electricity, industrialists may want more dams. But this may submerge the land and disrupt the lives of people who are displaced – such as tribals. They might resent this and may prefer small check dams or tanks to irrigate their land. Answer the following MCQs by choosing the most appropriate option: (A) Which one of the following is a developmental goal for labour unions? (a) To get labour rules which benefit the labourers if implemented (b) To get more buildings made (c) To get more electricity (d) To get more money Answer: (a) To get labour rules which benefit the labourers if implemented (B) which of the following statements is correct about developmental goals? (a) They are the same for all the citizens of a country. (b) They are different and sometimes even contradictory for different groups and people. (c) There are no developmental goals. (d) These goals do not matter. Answer: (C) What will be the top priority in the developmental goal of a native craftsman? (a) Expansion of rural banking (b) More days of work and better wages (c) Metal roads for transportation (d) More demand of local and handmade goods Answer: (d) More demand of local and handmade goods (D) Which two groups have conflicting interests according to the source? (a) The girls and the boy (b) The tribals and the industrialists (c) Companies fighting for one project (d) The tribals against one another Answer: (b) The tribals and the industrialists Very Short Answer Type Questions Question 1. Suggest any one way to create employment in Semi-rural areas. Answer: Capacity building and establishing of food processing units in Semi Rural areas can help create employment in Semi-Rural areas. Question 2. State any two goals of development other than Income. Answer: Values like Peace and Freedom; Healthy environment. Question 3. Why does Kerala have a Low Infant Mortality Rate? Answer: Availability of Healthcare and medical facilities helps it have a low mortality rate. Question 4. What is the development goal of rural people of India as per your viewpoint? Answer: To have access to better resources like food, transportation and communication facilities. Question 5. What is the advantage of knowing per capita income? Mention any one. Answer: Knowing per capita income for a country helps to compare and analyze wealth of different countries and measure their,. economic development. It can be used as a measure of nation’s standard of living. Question 6. What is the full form of HDI? Answer: Human Development Index. Question 7. According to the World Bank (2004), which country would be classified as a low income country? Answer: Question 8. If there are 4 families in a country with per capita income of 15,000$. The income of 3 families is $10,000,$ 20,000 and \$12,000. What is the income of the 4th family?
Per Capita Income = Average Income = Sum of income of all units/Total units
= 10,000 + 20,000 + 12,000 + A/4 = 15,000
= 15,000 x 4 = 10,000+20,000+12,000 + A
= 60,000 – (10,000 + 20,000 + 12,000 + A)
A = 60,000 – 42,000
A = Rs. 18,000

Question 9.
“There is enough for everybody’s need but not for everybody’s greed.” Who said these words? [CBSE 2014]
Mahatma Gandhi

Question 10.
Why do some people oppose dams? Give one reason.
Displacement of homes, destruction of natural habitat makes adivasis in India oppose the construction of dams.

Question 11.
How can development be made sustainable? Illustrate with examples from everyday life.
Development can be made sustainable if the existing resources are used in a planned manner. Emphasis should be developing renewable sources of energy and recycling of metals.

Question 12.
Define the term ‘literacy rate’.

Question 13.
Defirle the term ‘Uteracy rate’.

Question 14.
What may be one of the developmental goals of a girl who belongs to a rich urban family? [CBSE 2019,14,11]
the developmental goals of a girl who belongs to a rich urban family may be getting the same freedom as her brother, pursue higher studies and a high standard of living.

Related Theory
A development goal is a target or an aim that a person wants to achieve by developing himself/ herself. Alt people have different development goals according to the situation they are in or the work they do.

Question 15.
How can two people have different developmental goals ? [CBSE 2018]
Different people have different developmental goals because people come from different backgrounds and have different dreams and aspirations.

Related Theory
People set their goals according to the changing circumstances and the prevailing situation and may also change the goal with the change in situation which could be contradictory to the previous goal.

Question 16.
Define IMR.
The number of children that die before the age of one year as a proportion of 1000 live children born in that particular year, is called infant mortality rate or IMR.

Question 17.
What may be one of the developmental goals of b rich farmer? [CBSE 2019,15]
The developmental goals of a rich farmer might be gaining high profits on the produce or availability of cheap labour to work in the farm.

Question 18.
Define the term ‘per capita income’.
Per capita income is calculated as the average income of a citizen of a country. Per capita Income = total income of a country/total population

Question 19.
What may be a developmental goal of farmers who depend only on rain for growing crops?
The development goal of a farmer who is only dependent on rain for growing crop, would be a good and sufficient monsoon season so that his crops get the required irrigation and he can benefit from the good produce.

Related Theory
Developmental goal is a target or an aim that a person wants to achieve by developing himself/ herself. All people have different development goals according to the situation they are in or the work they do.

Question 20.
Mention the formula to calculate the BMI (Body Mass Index).
BMI: (BODY MASS INDEX)
Weight of person in kg and height in metres is taken. Divide the weight by the square of the height.

Question 21.
What may be a developmental goal of the urban unemployed youth? [CBSE 2019,12]
The development goal of an urban unemployed youth would be to find a good job and earn a decent wage with that work. He/she will aspire to maintain a good standard of living.

Question 22.
What criteria does UNDP compare to measure the human development index?
UNDP compares countries based on the educational levels of the people, their health status and per capita income.

Related Theory
UNDP compares countries based on these aspects and prepares a Human Development Report.

## MCQ Questions for Class 11 Maths Chapter 8 Binomial Theorem with Answers

Check the below NCERT MCQ Questions for Class 11 Maths Chapter 8 Binomial Theorem with Answers Pdf free download. MCQ Questions for Class 11 Maths with Answers were prepared based on the latest exam pattern. We have provided Binomial Theorem Class 11 Maths MCQs Questions with Answers to help students understand the concept very well.

Online Binomial Expansion Calculator and find the expansion of the given binomial term.

## Binomial Theorem Class 11 MCQs Questions with Answers

MCQ On Binomial Theorem Class 11 Question 1.
The coefficient of y in the expansion of (y² + c/y)5 is
(a) 10c
(b) 10c²
(c) 10c³
(d) None of these

Hint:
Given, binomial expression is (y² + c/y)5
Now, Tr+1 = 5Cr × (y²)5-r × (c/y)r
= 5Cr × y10-3r × Cr
Now, 10 – 3r = 1
⇒ 3r = 9
⇒ r = 3
So, the coefficient of y = 5C3 × c³ = 10c³

Binomial Theorem MCQ Question 2:
(1.1)10000 is _____ 1000
(a) greater than
(b) less than
(c) equal to
(d) None of these

Hint:
Given, (1.1)10000 = (1 + 0.1)10000
10000C0 + 10000C1 × (0.1) + 10000C2 ×(0.1)² + other +ve terms
= 1 + 10000×(0.1) + other +ve terms
= 1 + 1000 + other +ve terms
> 1000
So, (1.1)10000 is greater than 1000

The Chebyshev’s Theorem Calculator calculator shows steps for finding the smallest percentage of data values within ‘k’ standard deviations

MCQ On Binomial Theorem Question 3.
The fourth term in the expansion (x – 2y)12 is
(a) -1670 x9 × y³
(b) -7160 x9 × y³
(c) -1760 x9 × y³
(d) -1607 x9 × y³

Answer: (c) -1760 x9 × y³
Hint:
4th term in (x – 2y)12 = T4
= T3+1
= 12C3 (x)12-3 ×(-2y)³
= 12C3 x9 ×(-8y³)
= {(12×11×10)/(3×2×1)} × x9 ×(-8y³)
= -(2×11×10×8) × x9 × y³
= -1760 x9 × y³

MCQs On Binomial Theorem Question 4.
If n is a positive integer, then (√3+1)2n+1 + (√3−1)2n+1 is
(a) an even positive integer
(b) a rational number
(c) an odd positive integer
(d) an irrational number

Hint:
Since n is a positive integer, assume n = 1
(√3+1)³ + (√3−1)³
= {3√3 + 1 + 3√3(√3 + 1)} + {3√3 – 1 – 3√3(√3 – 1)}
= 3√3 + 1 + 9 + 3√3 + 3√3 – 1 – 9 + 3√3
= 12√3, which is an irrational number.

Binomial Theorem Class 11 MCQ Question 5.
If the third term in the binomial expansion of (1 + x)m is (-1/8)x² then the rational value of m is
(a) 2
(b) 1/2
(c) 3
(d) 4

Hint:
(1 + x)m = 1 + mx + {m(m – 1)/2}x² + ……..
Now, {m(m – 1)/2}x² = (-1/8)x²
⇒ m(m – 1)/2 = -1/8
⇒ 4m² – 4m = -1
⇒ 4m² – 4m + 1 = 0
⇒ (2m – 1)² = 0
⇒ 2m – 1 = 0
⇒ m = 1/2

Binomial Theorem MCQ Pdf Question 6.
The greatest coefficient in the expansion of (1 + x)10 is
(a) 10!/(5!)
(b) 10!/(5!)²
(c) 10!/(5! × 4!)²
(d) 10!/(5! × 4!)

Hint:
The coefficient of xr in the expansion of (1 + x)10 is 10Cr and 10Cr is maximum for
r = 10/ = 5
Hence, the greatest coefficient = 10C5
= 10!/(5!)²

Binomial Theorem MCQs With Answers Pdf Question 7.
The coefficient of xn in the expansion of (1 – 2x + 3x² – 4x³ + ……..)-n is
(a) (2n)!/n!
(b) (2n)!/(n!)²
(c) (2n)!/{2×(n!)²}
(d) None of these

Hint:
We have,
(1 – 2x + 3x² – 4x³ + ……..)-n = {(1 + x)-2}-n
= (1 + x)2n
So, the coefficient of xnC3 = 2nCn = (2n)!/(n!)²

Binomial Theorem MCQ With Solution Question 8.
The value of n in the expansion of (a + b)n if the first three terms of the expansion are 729, 7290 and 30375, respectively is
(a) 2
(b) 4
(c) 6
(d) 8

Hint:
Given that the first three terms of the expansion are 729, 7290 and 30375 respectively.
Now T1 = nC0 × an-0 × b0 = 729
⇒ an = 729 ……………. 1
T2 = nC1 × an-1 × b1 = 7290
⇒ n
an-1 × b = 7290 ……. 2
T3 = nC2 × an-2 × b² = 30375
⇒ {n(n-1)/2}
an-2 × b² = 30375 ……. 3
Now equation 2/equation 1
n
an-1 × b/an = 7290/729
⇒ n×b/n = 10 ……. 4
Now equation 3/equation 2
{n(n-1)/2}
an-2 × b² /n
an-1 × b = 30375/7290
⇒ b(n-1)/2a = 30375/7290
⇒ b(n-1)/a = (30375×2)/7290
⇒ bn/a – b/a = 60750/7290
⇒ 10 – b/a = 6075/729 (60750 and 7290 is divided by 10)
⇒ 10 – b/a = 25/3 (6075 and 729 is divided by 243)
⇒ 10 – 25/3 = b/a
⇒ (30-25)/3 = b/a
⇒ 5/3 = b/a
⇒ b/a = 5/3 …………….. 5
Put this value in equation 4, we get
n × 5/3 = 10
⇒ 5n = 30
⇒ n = 30/5
⇒ n = 6
So, the value of n is 6

Maths MCQs For Class 11 With Answers Pdf Question 9.
If α and β are the roots of the equation x² – x + 1 = 0 then the value of α2009 + β2009 is
(a) 0
(b) 1
(c) -1
(d) 10

Hint:
Given, x² – x + 1 = 0
Now, by Shridharacharya formula, we get
x = {1 ± √(1 – 4×1×1) }/2
⇒ x = {1 ± √(1 – 4) }/2
⇒ x = {1 ± √(-3)}/2
⇒ x = {1 ± √(3 × -1)}/2
⇒ x = {1 ± √3 × √-1}/2
⇒ x = {1 ± i√3}/2 {since i = √-1}
⇒ x = {1 + i√3}/2, {–1 – i√3}/2
⇒ x = -{-1 – i√3}/2, -{-1 + i√3}/2
⇒ x = w, w² {since w = {-1 + i√3}/2 and w² = {-1 – i√3}/2 }
Hence, α = -w, β = w²
Again we know that w³ = 1 and 1 + w + w² = 0
Now, α2009 + β2009 = α2007 × α² + β2007 × β²
= (-w)2007 × (-w)² + (-w²)2007 × (-w²)² {since 2007 is multiple of 3}
= -(w)2007 × (w)² – (w²)2007 × (w4)
= -1 × w² – 1 × w³ × w
= -1 × w² – 1 × 1 × w
= -w² – w
= 1 {since 1 + w + w² = 0}
So, α2009 + β2009 = 1

MCQ Questions For Class 11 Maths With Answers Pdf Question 10.
The general term of the expansion (a + b)n is
(a) Tr+1 = nCr × ar × br
(b) Tr+1 = nCr × ar × bn-r
(c) Tr+1 = nCr × an-r × bn-r
(d) Tr+1 = nCr × an-r × br

Answer: (d) Tr+1 = nCr × an-r × br
Hint:
The general term of the expansion (a + b)n is
Tr+1 = nCr × an-r × br

MCQ Questions For Class 11 Maths With Answers Question 11.
The coefficient of xn in the expansion (1 + x + x² + …..)-n is
(a) 1
(b) (-1)n
(c) n
(d) n+1

Hint:
We know that
(1 + x + x² + …..)-n = (1 – x)-n
Now, the coefficient of x = (-1)n × nCn
= (-1)n

Question 12.
If n is a positive integer, then (√5+1)2n + 1 − (√5−1)2n + 1 is
(a) an odd positive integer
(b) not an integer
(c) none of these
(d) an even positive integer

Hint:
Since n is a positive integer, assume n = 1
(√5+1)² + 1 − (√5−1)² + 1
= (5 + 2√5 + 1) + 1 – (5 – 2√5 + 1) + 1 {since (x+y)² = x² + 2xy + y²}
= 4√5 + 2, which is not an integer

Question 13.
In the expansion of (a + b)n, if n is even then the middle term is
(a) (n/2 + 1)th term
(b) (n/2)th term
(c) nth term
(d) (n/2 – 1)th term

Answer: (a) (n/2 + 1)th term
Hint:
In the expansion of (a + b)n,
if n is even then the middle term is (n/2 + 1)th term

Question 14.
In the expansion of (a + b)n, if n is odd then the number of middle term is/are
(a) 0
(b) 1
(c) 2
(d) More than 2

Hint:
In the expansion of (a + b)n,
if n is odd then there are two middle terms which are
{(n + 1)/2}th term and {(n+1)/2 + 1}th term

Question 15.
if n is a positive ineger then 23nn – 7n – 1 is divisible by
(a) 7
(b) 9
(c) 49
(d) 81

Hint:
Given, 23n – 7n – 1 = 23×n – 7n – 1
= 8n – 7n – 1
= (1 + 7)n – 7n – 1
= {nC0 + nC1 7 + nC2 7² + …….. + nCn 7n} – 7n – 1
= {1 + 7n + nC2 7² + …….. + nCn 7n} – 7n – 1
= nC2 7² + …….. + nCn 7n
= 49(nC2 + …….. + nCn 7n-2)
which is divisible by 49
So, 23n – 7n – 1 is divisible by 49

Question 16.
In the binomial expansion of (71/2 + 51/3)37, the number of integers are
(a) 2
(b) 4
(c) 6
(d) 8

Hint:
Given, (71/2 + 51/3)37
Now, general term of this binomial Tr+1 = 37Cr × (71/2)37-r × (51/3)r
⇒ Tr+1 = 37Cr × 7(37-r)/2 × (5)r/3
This General term will be an integer if 37Cr is an integer, 7(37-r)/2 is an integer and (5)r/3 is an integer.
Now, 37Cr will always be a positive integer.
Since 37Cr denotes the number of ways of selecting r things out of 37 things, it can not be a fraction.
So, 37Cr is an integer.
Again, 7(37-r)/2Cr will be an integer if (37 – r)/2 is an integer.
So, r = 1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, 31, 33, 35, 37 …………. 1
And if (5)r/3 is an integer, then r/3 should be an integer.
So, r = 0, 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36 ………….2
Now, take intersection of 1 and 2, we get
r = 3, 9, 15, 21, 27, 33
So, total possible value of r is 6
Hence, there are 6 integers are in the binomial expansion of (71/2 + 51/3)37

Question 17.
The number of ordered triplets of positive integers which are solution of the equation x + y + z = 100 is
(a) 4815
(b) 4851
(c) 8451
(d) 8415

Hint:
Given, x + y + z = 100;
where x ≥ 1, y ≥ 1, z ≥ 1
Let u = x – 1, v = y – 1, w = z – 1
where u ≥ 0, v ≥ 0, w ≥ 0
Now, equation becomes
u + v + w = 97
So, the total number of solution = 97+3-1C3-1
= 99C2
= (99 × 98)/2
= 4851

Question 18.
The greatest coefficient in the expansion of (1 + x)10 is
(a) 10!/(5!)
(b) 10!/(5!)²
(c) 10!/(5! × 4!)²
(d) 10!/(5! × 4!)

Hint:
The coefficient of xr in the expansion of (1 + x)10 is 10Cr and 10Cr is maximum for
r = 10/2 = 5
Hence, the greatest coefficient = 10C5
= 10!/(5!)²

Question 19.
If the third term in the binomial expansion of (1 + x)m is (-1/8)x² then the rational value of m is
(a) 2
(b) 1/2
(c) 3
(d) 4

Hint:
(1 + x)m = 1 + mx + {m(m – 1)/2}x² + ……..
Now, {m(m – 1)/2}x² = (-1/8)x²
⇒ m(m – 1)/2 = -1/8
⇒ 4m² – 4m = -1
⇒ 4m² – 4m + 1 = 0
⇒ (2m – 1)² = 0
⇒ 2m – 1 = 0
⇒ m = 1/2

Question 20.
In the binomial expansion of (a + b)n, the coefficient of fourth and thirteenth terms are equal to each other, then the value of n is
(a) 10
(b) 15
(c) 20
(d) 25