Category: CBSE Class 10

In this page, we are providing Control and Coordination Class 10 Extra Questions and Answers Science Chapter 7 pdf download. NCERT Extra Questions for Class 10 Science Chapter 7 Control and Coordination with Answers will help to score more marks in your CBSE Board Exams. https://ncertmcq.com/extra-questions-for-class-10-science/

Class 10 Science Chapter 7 Extra Questions and Answers Control and Coordination

Extra Questions for Class 10 Science Chapter 7 Control and Coordination with Answers Solutions

Extra Questions for Class 10 Science Chapter 7 Very Short Answer Type

Question 1.
Define ‘reflex action’.  [CBSE 2009]
Answer:
It is an automatic, spontaneous and an immediate involuntary response to a stimulus controlled usually by the spinal cord. e.g. knee jerk movement.

Question 2.
Name the largest cell in the human body.  [CBSE 2003]
Answer:
Nerve cell (Neuron).

Question 3.
Give an example of plant hormone that promotes growth.  [CBSE 2008]
Answer:
Auxin

Question 4.
What are plant hormones?  [CBSE 2008]
Answer:
The chemical substances produced in plants which help in the growth and development of plant, its tissues and other plants.

Question 5.
Name the part of neuron   [CBSE 2008]
(а) where information is acquired.
(b) through which information travels an electrical impulse.
Answer:
(a) Dendrite
(b) Axon

Question 6.
Name two tissues that provide control and coordination in multicellular animals.  [CBSE 2009]
Answer:
Muscular tissues and nervous tissue.

Question 7.
Name the hormone, the secretion of which is responsible for dramatic changes in appearance in girls and boys when they approach 10-12 years of age.   [CBSE 2008]
Answer:
Testosterone released from testes in males, estrogen released from ovaries in females.

Question 8.
Name the hormone that helps in regulating level of sugar in our blood. Name the glands that secretes it. [CBSE 2010]
Answer:
Insulin hormone secreted by pancreas.

Question 9.
Name a plant hormone that inhibits growth. Write its one more function.  [CBSE 2014]
Answer:
Abscisic acid inhibits growth in plants. It also causes closure of stomata during water stress.

Question 10.
A potted plant is made to lie horizontally on the ground. Which part of the plant will show:
(i) Positive geotropism
(ii) Negative geotropism  [CBSE 2010]
Answer:
(i) Roots will shows positive geotropism.
(ii) Shoots will show negative geotropism.

Question 11.
Name a plant hormone which promotes growth in plants.  [CBSE 2008]
Answer:
Auxin is a plant hormone that promotes growth and cell elongation in plants.

Question 12.
State one function each of pons and cerebellum.
Answer:
Pons: Regulates rate of respiration
Cerebellum: Maintains equilibrium of the body during walking, jumping, etc.

Question 13.
Name a gaseous plant hormone. Give its role.
Answer:
Ethylene is a gaseous hormone. It regulates fruit ripening.

Question 14.
How many spinal and cranial nerves are present in human body?
Answer:
Spinal nerves = 31 pairs
Cranial nerves = 12 pairs

Question 15.
What are meninges?
Answer:
The three membranes which cover the brain to protect it are called meninges.

Extra Questions for Class 10 Science Chapter 7 Short Answer Type I

Question 1.
How do we detect smell of hot spicy food from a distance?
Answer:
We have olfactory receptors in our nose which detect the smell of hot spicy food.
This information is transmitted by nerve impulse to olfactory lobes of forebrain which interpret the information.

Question 2.
Why do tendrils coil around hard objects or support?
Answer:
The tendrils coil around hard objects or support due to a stimulus of touch (thigmotropism) which causes less growth on the side in contact with support than the side which is away from it. This unequal growth of two sides of tendril makes it coil around the support.

Question 3.
Name the hormones reponsible for regulation.
(i) Metabolism of carbohydrates, fats and proteins
(ii) Balance of calcium and phosphate
(iii) Blood pressure
(iv) Water and electrolyte balance.  [CBSE 2007]
Answer:
(i) Thyroxin
(ii) Parathyroid hormone
(iii) Adrenaline
(iv) Vasopressin

Question 4.
What is an association neuron?
Answer:
Association neurons are present in cortex part of spinal cord between the sensory neuron and motor neuron. It helps to interconnect the signals between the sensory neuron and motor neuron by forming synapse with axon of sensory neuron and dendrite of motor neuron.

Question 5.
How are the brain and spinal cord protected from mechanical shock?
Answer:
Brain is present in a bony box called cranium (skull), spinal cord is protected by vertebral column. The cerebrospinal fluid present around the brain and spinal cord protect it from mechanical shock.

Question 6.
Which functions are regulated by the forebrain?
Answer:
The thinking part of the brain is forebrain which controls

• Movement of voluntary muscles.
• Hearing, smell, sight, hunger, thirst, pain, etc. by its association areas.
• It also stores information and controls intelligence.

Question 7.
Explain how a squirrel responds a dangerous situation with help of its hormonal system.
Answer:
When a squirrel perceives a dangerous situation, adrenaline hormone is released in its blood which increases its heart beat and blood supply to tissues. This provides energy to its cells and tissues at a faster rate and enables it to run away from emergency situation.

Question 8.
How are sensory neurons different from motor neurons?
Answer:
Sensory neuorons take information from receptors and transmit the impulses towards central nervous system. Motor neurons carry message from control nervous system to the muscle, gland or an organ to enable it to respond.

Question 9.
How are receptors different from effectors?
Answer:
Receptors are cells, tissues or organs which receive the information in form of stimulus. For example, photoreception, gustatory receptors, etc. Effectors are muscles, glands tissues or cells which respond according to the information received through motor neuron from the central nervous system.

Question 10.
Define peripheral nervous system. What are its components?
Answer:
The nerves that directly arise from the central nervous system and contact different parts of our body to help their involuntary controls. Spinal nerves and cranial nerves are components of peripheral nervous system.

Question 11.
Lable the parts (a), (b), (c) and (d) and show the direction of flow of electrical signals in the given figure.

Answer:
(a) Sensory neuron
(b) Spinal cord (part of CNS)
(c) Motor neuron
(d) Effector (Muscle)

Question 12.
Name the plant hormones responsible for the following:
(a) elongation of cells
(b) growth of stem
(c) promotion of cell division
(d) falling of senescent leaves
Answer:
(a) Auxin
(b) Gibberellin
(c) Cytokinin
(d) Abscissic acid

Question 13.
Label the endocrine glands in figure given below.

Answer:
(a) Pineal Gland
(b) Pituitary Gland
(c) Thyroid
(d) Thymus

Question 14.
Label the parts of a neuron in figure given below.

Answer:
(a) Dendrite
(b) Cell Body
(c) Axon
(d) Nerve ending

Question 15.
Match the terms of Column (A) with those of Column (B)

[NCERT Exemplar]
Answer:
(a) (iii)
(b) (iv)
(c) (i)
(d) (ii)

Extra Questions for Class 10 Science Chapter 7 Short Answer Type II

Question 1.
What are nastic and curvature movements? Give one example of each.  [CBSE 2010]
Answer:
The non-directional responses to stimuli are called nastic movements e.g., drooping of leaves of touch-me-not plant. Curvature movement are the movement of plant parts towards or away from stimulus e.g., bending of shoot towards light.

Question 2.
How does feedback mechanism regulate the hormone action? Explain with the help of an example.
Answer:
The presence or absence of a particular hormone can regulate its further formation with the help of a regulatory mechanism called feedback mechanism.

Example: Hypothalamus regulates thyroxin levels in blood by secreting thyroid stimulating hormone (TSH). If the thyroxine levels increases then hypothalamus stop secreting TSH in order to reduce the production of thyroxine from thyroid gland.

Low levels of thyroxin in blood again switches on the release of TSH from hypothalamus to increase levels of thyroxin in blood.

Question 3.
What are the different types of neurons and their functions in the human body?
Answer:
There are mainly three types of neurons:

1. Sensory neuron: They transmit information from receptors towards the central nervous system.
2. Motor neuron: They transmit information from the central nervous system to effectors like muscles or glands.
3. Relay neuron: It serves as a link between the sensory and the motor neurons in the brain or spinal cord.

Question 4.
What are the limitations to the use of electrical impulse?
Answer:
The limitations to electrical impulse are

1. Only those cells used that are connected by nervous tissue, while other tissues do not receive the information directly.
2. It takes some times to reset the mechanism of generation of new electrical impulse once an electrical impulse had been generated.

Question 5.
Depict the mechanism of Nervous tissue action.
Answer:
The mechanism of nervous tissue action is:

Question 6.
What is a tropic movement? Explain with an example. [NCERT Exemplar]
Answer:
The directional movements caused in plants due to an external stimuli are called tropic movements.
Example: During phototropism, the shoot bends towards light and show positive phototropism while the roots bend away from light to show negative phototropism.

Question 7.
What will happen if intake of iodine in our diet is low?  [NCERT Exemplar]
Answer:
Iodine helps in the synthesis of thyroxin hormone from thyroid gland. Thyroxin hormone is necessary for carbohydrate, proteins and fat metabolism.
Deficiency caused due to low level of iodine in diet might result is a disease called goitre in the person.

Question 8.
Answer the following:
(a) Which hormone is responsible for the changes noticed in females at puberty?
(b) Dwarfism results due to deficiency of which hormone?
(c) Blood sugar level rises due to deficiency of which hormone?
(d) Iodine is necessary for the synthesis of which hormone?  [NCERT Exemplar]
Answer:
(a) Oestrogen
(b) Growth hormone
(c) Insulin
(d) Thyroxin

Question 9.
Answer the following:
(a) Name the endocrine gland associated with brain.
(b) Which gland secretes digestive enzymes as well as hormones?
(c) Name the endocrine gland associated with kidneys.
(d) Which endocrine gland is present in males but not in females?  [NCERT Exemplar]
Answer:
(a) Pituitary
(b) Pancreas
(c) Adrenal gland
(d) Testes

Extra Questions for Class 10 Science Chapter 7 Long Answer Type

Question 1.
Differentiate between tropic and nastic movements in plants.  [CBSE 2006]
Answer:
Tropic Movements:

1. There is directional growth of a plant or part of a plant in response to an external stimulus i.e., direction of stimulus controls direction of growth.
2. The effect is more or less permanent.
3. It is easily observed in stems and roots of plants.
4. It occurs due to unequal growth on the two sides of a stem or root.
5. For example, bending of root towards gravity and bending of shoot towards light.

Nastic Movements:

1. The growth or movement is independent of the direction of stimulus.
2. The effect is temporary and reversible.
3. It occurs in specialised parts and organs of plants like leaves and petals of flowers.
4. It usually involves alterations in cell volumes.
5. For example, folding on leaflets of touch-me-not plant on touching them.

Question 2.
Mention one function for each of these hormones:
(a) Thyroxin
(b) Insulin
(c) Adrenaline
(d) Growth hormone
(e) Testosterone
Answer:
(a) Thyroxin: It regulates carbohydrates, fat and protein metabolism.
(b) Insulin: It regulates blood sugar level.
(c) Adrenaline: It increases heart beat rate and supply of blood to various organs.
(d) Growth hormones: It regulates growth and development of an organism.
(e) Testosterone: It controls the bodily features, secondary sexual characters in males during puberty.

Question 3.
How does chemical coordination take place in animals?
Answer:
Hormones secreted by the endocrine glands are directly poured into the blood stream as they are ductless glands. Blood carries these hormones to specific target tissue or organ where they act and trigger a particular biochemical or physiological activity in response to the stimulus received.

Question 4.
Why is the flow of signals in a synapse from axonal end of one neuron to dendritic end of another neuron but not the reverse?  [NCERT Exemplar]
Answer:
The information received by the dendrites of neurons present at receptors is transferred in form of electrical impulse to the cell body, axon and the nerve endings at the ends of axon. At the axonal ends, chemicals are released between junction of two neurons called synapse. The chemical diffuses towards the dendrite of the next neuron where it generates an electrical impulse again. So, the electrical signals change to chemical signals and again to electrical signals for the next neuron.

Since the chemicals Eire released at the axonal ends and absent at dendrite end, the signal travels from axonal end to dendritic end of another neuron but not the reverse i.e., the flow of electrical impulse is unidirectional only.

Control and Coordination HOTS Questions With Answers

Question 1.
While most of our actions are coordinated by the brain, still some of our actions need to be coordinated by the spinal cord. Why?
Answer:
Brain is the thinking part which coordinates the various activities and processes in human beings. But, some actions which need to be quick, automatic and involuntary, do not involve any thinking processes.
So, such immediate responses are coordinated by the spinal cord and are called reflex actions.

Question 2.
The movements shown by the leaves of ‘touch me not’ plant on touching are different from the movement shown by seedling. Elaborate.
Answer:
The opening and closing of the leaves of the ‘touch me not plant’ is a result of water change in amount of water in the plant cells, which is not dependent on growth. But, the movement of the seedling is a growth-dependent movement because it will not show any movement if it is prevented from growth.

Question 3.
The level of hormones should be well balanced in human beings in order to maintain the normal functioning of the human body. Explain this statement with two examples.
Answer:
The level of hormones should be balanced in human beings because a deficiency or excess secretion of some hormones can have adverse effects on the human body. For example,

• A deficiency in the secretion of insulin from the pancreas increases the blood sugar level and causes diabetes.
• A deficiency in the secretion of growth hormone causes dwarfism whereas it excess secretion causes gigantism.

Question 4.
Chemical coordination plays a vital role in the activities of plants. Elaborate.
Answer:
Coordination in human beings is carried out both by the nervous as well as the hormonal system. But, coordination in plants is dependent on the chemicals called as hormones. The hormone auxin and gibberellins help in the growth of the stem. Cytokinins help in cell division. Abscisic acid inhibits growth. Auxin is also involved in the bending of plants towards light.

Question 5.
The response of the body due to reflex actions is faster than those carried out by secretion of adrenaline in emergency situations. Why?
Answer:
The reflex actions are the result of chemical-electrical impulses which are faster as they move through the nerve cell from one point to another, whereas, hormones are first released in the blood and they have to travel to the target site to bring about the response, which takes more time than reflex actions.

Extra Questions for Class 10 Science Chapter 7 Value Based Questions

Question 1.
Villagers living in a hilly area were facing a problem that a lot of children in the village were developing swollen necks. The priest of the village told that it was due to the acts of the villagers who had annoyed their Goddess and they needed to offer sacrifice for getting rid of this problem. Dr. Kamal visited the village and properly listened to the problem of the villagers and advised them to use iodised salt instead of normal salt in their food. Villagers agreed to Dr. Kamal’s advice and within a few months the problem was overcome to a large extent.
(a) What was the cause of the swollen neck of children in the village?
(b) What values are shown by Dr. Kamal?
(c) Why was use of iodised salt advised to villagers by Dr. Kamal?
Answer:
(a) The swollen neck is a disease called goitre. Goitre occurs due to deficiency of thyroxine hormone.
(b) Scientific aptitude, patience, problem solving ability and helpful nature.
(c) The use of iodised salt was advised because Iodine helps in production of thyroxine hormone which helps to prevent goitre.

Question 2.
Akhilesh saw a plant in his school garden which closed its leaves on touching. He observed the plant very closely for a long time. In the recess, he saw that some students were trying to pluck the plant from the pot. He went to them and advised them not to pluck the plant as it was their school’s property. He also told them about the importance of the plants and the peculiar behavior of the said plant. In this way, he was able to convince the students to not harm the plant.
(a) Why did the leaves of the plant close on touching?
(b) How is this response of plant different from reflex action in animals?
(c) What values are shown by Akhilesh?
Answer:
(a) The leaves of the sensitive plants like Touch-me-not close on touching as they lose the turgor pressure in cells which causes drooping of its leaves/leaflets.

(b)
Movement in Sensitive Plant:

1. The response is produced due to the change in amount of water in the plant cells.
2. No nerve or specialised tissue involved in the conduction of information.

Reflex action:

1. An automatic, immediate, involuntary response of an organism.
2. It is controlled by the spinal cord.

(c) Environment friendly, responsible, leadership, analytical thinking.

Question 3.
Smita’s father was complaining about frequent urination, pain in legs and a frequent weight loss to Smita’s mother and she discussed the things with her daughter when Smita returned from school. Listening to this Smita told her mother that her father should go and visit a doctor immediately. The doctor diagnosed that Smita’s father was having an elevated level of blood glucose. He should take care of his diet and should exercise regularly to maintain his normal glucose level.
On the basis of the text, answer the following questions:
(i) Name the disease he is suffering from and name the hormone whose deficiency causes it.
(ii) Identify the gland that secretes it and mention the function of this hormone.
(iii) Explain how the time and amount of secretion of this hormone is regulated in human system.
(iv) What values were shown by Smita and her father? [CBSE 2012, 2015]
Answer:
(i) Disease-Diabetes, Hormone: Insulin (deficiency of insulin hormone causes diabetes)
(ii) Gland-Pancreas: The blood glucose level is regulated by insulin hormone secreted by the pancreas.
(iii) Cells of pancreas secrete insulin hormone when level of blood glucose level increases in the blood. Insulin regulates the blood glucose level and its secretion gets reduced when blood glucose level falls down.
(iv) Decision making, intelligence, scientific aptitude and caring nature is shown by Smita. Her father had shown an attitude of carelessness towards his health.

Question 4.
Rajesh found an old man lying on the road asking for help to take him to the hospital. He took the old man to the hospital where doctor told him that the old man was suffering from paralysis, and his blood sugar levels were high. The doctor told him that they have given the old man some injections to reduce the blood sugar level and thanked Rajesh for his helpful attitude.
On the basis of above passage, answer the following:
(i) What can be the cause of high blood sugar levels in the old man?
(ii) Which part of old man’s body might have been effected that has caused paralysis?
(iii) What values have been shown by Rajesh?
(iv) Which injection might have been given to old man by doctor to lower the blood sugar levels?
Answer:
(i) Diabetes due to the lower levels of insulin hormone in the body.
(ii) Nervous system associated with brain or spinal cord might have been effected.
(iii) Helpful, care for elderly.
(iv) Injections of insulin might have been given by the doctor to the old man to lower his blood sugar levels.

In this page, we are providing Metals and Non-metals Class 10 Extra Questions and Answers Science Chapter 3 pdf download. NCERT Extra Questions for Class 10 Science Chapter 3 Metals and Non-metals with Answers will help to score more marks in your CBSE Board Exams. https://ncertmcq.com/extra-questions-for-class-10-science/

Class 10 Science Chapter 3 Extra Questions and Answers Metals and Non-metals

Extra Questions for Class 10 Science Chapter 3 Metals and Non-metals with Answers Solutions

Extra Questions for Class 10 Science Chapter 3 Very Short Answer Type

Metals And Non Metals Class 10 Extra Questions Question 1.
Name the property due to which metals have a shining surface in their pure state.
Answer:
Metallic lustre.

Class 10 Science Chapter 3 Extra Questions Question 2.
Name two most malleable metals.
Answer:
Gold and silver.

Metals And Non Metals Class 10 Extra Questions And Answers Question 3.
Name the most ductile metal.
Answer:
Gold.

Question Bank On Metals And Non-Metals Class 10 Question 4.
Name a metal which occurs in the free state.
Answer:
Gold.

Metal And Non Metals Class 10 Extra Questions Question 5.
Give an example of an elementary substance which is a good conductor of electricity but is not a metal.
Answer:
Graphite.

Ch 3 Science Class 10 Extra Questions Question 6.
Name two metals which are both malleable and ductile.
Answer:
Silver and gold.

Extra Questions Of Metals And Nonmetals Class 10 Question 7.
Name the non-metal which is a liquid.
Answer:
Bromine.

Metals And Non Metals Extra Questions Class 10 Question 8.
Expand PVC.
Answer:
Polyvinyl chloride.

Extra Questions On Metals And Nonmetals Class 10 Question 9.
Name a non-metal which is lustrous.
Answer:
Iodine.

Metals And Non Metals Extra Questions Question 10.
Metal A can displace metal B from BO, the oxide of metal B. Metal B can displace C from solution of CSO₄, the sulphate of metal C. Arrange metal A, B and C in the order of increasing reactivity.
Answer:
C < B < A.

Chapter 3 Science Class 10 Extra Questions Question 11.
Name two metals which can be cut with a knife.
Answer:
Lithium, sodium, potassium

Metals And Nonmetals Class 10 Extra Questions Question 12.
An element forms an oxide A₂O₃ which is acidic in nature. Identify A as a metal or non-metal.  [NCERT Exemplar]
Answer:
Oxides of non-metals are acidic in nature while those of metals are basic in nature. Hence, A must be a non-metal.

Metals And Non Metals Class 10 Question Answer Question 13.
Why does calcium float in water?
Answer:
Calcium reacts with water to form calcium hydroxide and hydrogen. Bubbles of hydrogen gas stick to the surface of calcium, hence it floats.

Class 10 Metals And Nonmetals Extra Questions Question 14.
Arrange the following metals in the decreasing order of reactivity Na, K, Cu, Ag.
Answer:
K > Na > Cu > Ag.

Metals And Nonmetals Class 10 Extra Questions And Answers Question 15.
Name the two metals which do not react with water at all.
Answer:
Lead, Copper, Silver and Gold

Question 16.
Name the element which shows non-metallic properties, but is also present in the activity series of metal.
Answer:
Hydrogen.

Question 17.
If X, Y, Z, W, A, B and C represents the metals in the decreasing order of their reactivity, which metal is most likely to occur in free state in nature?
Answer:
C is least reactive, hence .it is likely to occur in the free state.

Question 18.
Name any one metal which reacts neither with cold water nor with hot water, but reacts with heated steam to produce hydrogen gas.
Answer:
Iron
3Fe (s) + 4H₂O (g) → Fe₃O₄ (s) + 4H₂ (g)

Question 19.
Mention the composition of aqua regia.
Answer:
It is a freshly prepared mixture of concentrated hydrochloric acid and concentrated nitric acid in the ratio of 3:1.

Question 20.
In nature, metal A is found in the free state, while metal B is found in the form of its compounds. Which of these two will be nearer to the top of the activity series of metals?
Answer:
Metal B will be nearer to the top because it is more reactive as it is clear from the fact that it exists in the form of its compounds.

Question 21.
Name any two oxides ores.
Answer:

1. Haematite
2. Bauxite.

Question 22.
Which method is used for the concentration of sulphide ores?
Answer:
Froth flotation process.

Question 23.
Complete the chemical equation.

Answer:

Question 24.
What is galvanisation?
Answer:
Galvanisation is a method of protecting steel and iron from rusting by coating them with a thin layer of zinc.

Question 25.
24 Carat gold is not suitable for making jewellery. Why?
Answer:
24 carat gold is very soft, so it is alloyed with either silver or copper to make it hard.

Question 26.
How many carats is pure gold?
Answer:
24 carat.

Question 27.
Name the metal which is used for galvanising iron.
Answer:
Zinc (Zn).

Question 28.
What is meant by 22 carat gold?
Answer:
An alloy consisting of 22 parts by weight of pure gold and 2 parts by weight of copper or silver is called 22 carat gold.

Question 29.
What is an alloy?
Answer:
An alloy is a homogeneous mixture of two or more metals or a metal and a non-metal.

Question 30.
Why do shopkeepers apply oil on tools made of iron while storing them?
Answer:
To protect them from rusting as the oxygen and moisture of the atmosphere will not be able to come in direct contact with the surface of iron.

Question 31.
State two conditions for the rusting of iron.
Answer:

1. Presence of air (or oxygen).
2. Presence of water (or moisture).

Question 32.
Name two metals which are highly resistant to corrosion.
Answer:
Gold and platinum.

Question 33.
Name the gas in air which tarnishes silver particles slowly.
Answer:
Hydrogen sulphide (H₂S).

Extra Questions for Class 10 Science Chapter 3 Short Answer Type I

Question 1.
What happens when
(a) ZnCO₃ is heated in the absence of oxygen?
(b) a mixture of Cu₂O and Cu₂S is heated? [NCERT Exemplar]
Answer:
(a) A mixture of ZnO(s) and CO₂ is formed.

(b) A mixture of copper and SO₂ is formed.

Question 2.
Using the electronic configurations, explain how magnesium atom combines with oxygen atom to form magnesium oxide by transfer of electrons.
Answer:

Question 3.
Name two metals which react violently with cold water. Write any three observations you would make when such a metal is dropped into water. How would you identify the gas evolved, if any, during the reaction?   [CBSE 2008]
Answer:
Sodium, Potassium
When these metals are dropped in water, bubbles will be evolved due to evolution of hydrogen gas.
The gas will catch fire and the solution will be alkaline, i.e., it will turn red litmus blue.

Test: When a burning matchstick is brought near the gas, it burns explosively with a ‘pop’ sound and the splinter is extinguished.

Question 4.
State reasons for the following:
(i) Electric wires are covered with rubber-like material.
(ii) From dilute hydrochloric acid, zinc can liberate hydrogen gas but copper cannot.
Answer:
(i) It is because rubber is an insulator and does not allow current to flow through it.
(ii) Zinc is is placed above hydrogen in the reactivity series of metals while copper is placed below it. Metals placed above hydrogen can displace hydrogen from water and acids while those below it cannot. Therefore, zinc can displace hydrogen from dilute HCl whereas copper cannot.

Question 5.
Give the formulae of the stable binary compounds that would be formed by the combination of the following pairs of elements.
(a) Mg and N₂
(b) Li and O₂
(c) Al and Cl₂
(d) K and O₂
Answer:
(a) Mg₃N₂
(b) Li₂O
(c) AlCl₃
(d) K₂O

Question 6.
Compound X and aluminium are used to join railway tracks.
(a) Identify the compound X
(b) Name the reaction
(c) Write down its reaction.  [NCERT Exemplar]
Answer:
(a) Compound X must be iron (III) oxide, Fe₂O₃.
(b) The reaction is known as ‘thermite reaction’ or ‘aluminothermy’.
(c) The reaction is carried out by igniting the mixture with a Mg-ribbon.

Question 7.
Name two metals which will displace hydrogen from dilute acids, and two metals which will not.
Answer:
Zinc and magnesium can displace hydrogen from dilute acids whereas copper and silver cannot. The metals lying above hydrogen in the reactivity series can displace hydrogen on reaction with dilute acids.

Question 8.
During extraction of metals, electrolytic refining is used to obtain pure metals,
(a) Which material will be used as anode and cathode for refining of silver metal by this process?
(b) Suggest a suitable electrolyte also,
(c) In this electrolytic cell, where do we get pure silver after passing electric current?  [NCERT Exemplar]
Answer:
In the electrolytic refining of impure silver metal:
(a) A rod of impure silver is used as anode while that of pure silver as cathode.
(b) The electrolyte is a water soluble salt of silver, for example silver chloride or silver nitrate.
(c) On passing current, pure silver gets deposited at the cathode. It can be scrapped off later on.

Question 9.
Give reason for the following:
(i) Iron grills are frequently painted.
(ii) Gold ornaments retain their lustre even after several years of use.
Answer:
(i) Iron metal easily gets rusted by air containing moisture and oxygen. Therefore, iron grills are frequently painted with rust proof paints.
(ii) Gold is a noble metal and is not affected by chemicals or by air. Therefore, gold ornaments retain their lustre even after several years.

Question 10.
Name two metals which can be used to reduce metal oxides to metal.
Answer:
(i) Aluminium (Al)

(ii) Magnesium (Mg)

Question 11.
Give the reaction involved during extraction of zinc from its ore by
(a) roasting of zinc ore
(b) calcination of zinc ore   [NCERT Exemplar]
Answer:
(a) Roasting is done for the sulphide ore (zinc blende).

(b) Calcination is done for the carbonate ore (calamine).

Question 12.
The following reaction takes place when aluminium powder is heated with MnO2
3MnO₂(s) + 4Al(s) → 3Mn(l) + 2Al₂O₃(l) + Heat [NCERT Exemplar]
(a) Is aluminium getting reduced?
(b) Is MnO₂ getting oxidised?
Answer:
(a) Aluminium is getting oxidised to Al₂O₃.
(b) Manganese dioxide is getting reduced to Mn.

Question 13.
Differentiate between roasting and calcination process used in metallurgy. Give one example of each.
Answer:

Question 14.
Write chemical equations for the reactions taking place when
(a) Magnesium ribbon is burnt in a jar containing oxygen
(b) Sodium metal falls into a sink containing water
Answer:
(a)

(b) 2Na + 2H₂O → 2NaOH + H₂

Question 15.
What is an amalgam? Write the constituent metals of brass.
Answer:
An amalgam is an alloy in which one of the metals is mercury.
Brass is an alloy of copper and zinc (Cu and Zn). It contains 80% copper and 20% zinc.

Question 16.
Every ore is a mineral but not every mineral is an ore. Explain.
Answer:
Every mineral is not suitable for the extraction of the metal. The mineral from which the metal is economically and conveniently extracted is called an ore.

Extra Questions for Class 10 Science Chapter Short Answer Type II

Question 1.
What is an alloy? How is it prepared? Name the alloy which is used for welding electrical wires together.
Answer:
Alloy is a mixture of two or more metals or non-metals.
Alloys are made by mixing the metals in their molten state. It is prepared by first melting the primary metal and then dissolving the other metal in definite proportion. It is then cooled to room temperature. Solder is used for welding electrical wires together.

Question 2.
Give reasons for the following observations:
(i) Ionic compounds in general have high melting and boiling points.
(ii) Highly reactive metals cannot be obtained from their oxides by heating them with carbon.
(iii) Copper vessels get a green coat when left exposed to air in the rainy season.
Answer:
(i) Ionic compounds have high melting and boiling points due to strong force of attraction between oppositely charged ions.

(ii) It is because these metals, have great affinity towards oxygen and so cannot be reduced by carbon or carbon monoxide or hydrogen.

(iii) Copper vessels react with CO₂, O₂ and moisture to form green coloured basic copper carbonate [CuCO₃. CU(OH)₂] on their surface when exposed to moist air.

Question 3.
E is an element amongst copper, zinc, aluminium and iron. It shows the following properties:
Answer:
(a) One of its ores is rich in E₂O₃.
(b) E₂O₃ is not attacked by water.
(c) It forms two chlorides ECl₂ and ECl₃.
Name the element and justify your answer.
Answer:
The clue for the correct answer is the formation of ECl₂ and ECl₃. This shows that the element E has variable valencies of 2 and 3 out of the elements listed, only iron exists in divalent and trivalent forms.
(a) The ore rich in Fe₂O₃ is haematite.
(b) Haematite (Fe₂O₃) is not attacked by water.
(c) The two chlorides are: Iron (II) chloride or FeCl₂ and iron (III) chloride or FeCl₃.

Question 4.
When a metal X is treated with cold water, it gives a basic salt Y with molecular formula XOH (Molecular mass = 40) and liberates a gas Z which easily catches fire. Identify X, Y and Z and also write the reaction involved. [NCERT Exemplar]
Answer:
The base with molecular mass 40 is NaOH. Hence, the metal X must be sodium (Na). It reacts with H₂O to form the base NaOH and liberates H₂ gas which easily catches fire.

Question 5.
You are provided with three metals: Sodium, magnesium and copper. Using only water as the reactant, how will you identify them?
Answer:

• The metal which reacts violently with cold water and catches fire is sodium.
• The metal which evolves hydrogen gas upon heating with water is magnesium.
• The metal which does not react with water even on strong heating is copper.

Question 6.
A non-metal A is an important constituent of our food and forms two oxides B and C. Oxide B is toxic whereas C causes global warming.
(a) Identify A, B and C.
(b) To which Group of Periodic Table does A belong?  [NCERT Exemplar]
Answer:
The non-metal A is carbon. It is an important constituent of our food in different forms. For example, glucose (C₆H₁₂O₆) contains carbon. In fact, all food materials are organic compounds and these contain carbon as an essential constituent. The two oxides of carbon are, carbon monoxide (B) and carbon dioxide (C). Carbon dioxide causes global warming.

(a) A = Carbon (C); B = Carbon monoxide (CO); C = Carbon dioxide (CO₂)
(b) Carbon is the first member of group 14 in the long form of periodic table.

Question 7.
A non-metal X exists in two different forms Y and Z. Y is the hardest natural substance, whereas Z is a good conductor of electricity. Identify X, Y and Z.   [NCERT Exemplar]
Answer:
Non-metal ‘X’ must be carbon. It exist in two forms, diamond and graphite. Diamond is hardest natural substance. Hence, ‘Y’ is diamond. Graphite is a good conductor of electricity. Hence, ‘Z’ is graphite.

Question 8.
A metal E is stored under kerosene. When a small piece of it is left open in air, it catches fire. When the product formed is dissolved in water, it turns red litmus to blue.
(i) Name the metal E.
(ii) Write the chemical equation for the reaction when it is exposed to air and when the product is dissolved in water.
(iii) Explain the process by which the metal E is obtained from its molten chloride.
Answer:
(i) The available information suggests that the metal (E) is sodium (Na).

The solution is basic and it turns red litmus blue.
(iii) The metal is obtained by the process of electrolytic reduction.

Question 9.
Explain how the following metals are obtained from their compounds by reduction process:
(i) Metal X which is low in reactivity series
(ii) Metal Y which is in the middle of the series
(iii) Metal Z which is high up in the reactivity series.
Give one example of each type.
Answer:
(i) Metals which are low in reactivity series can be obtained by heating their compounds. For example, mercury is obtained by heating its ore, cinnabar (HgS), in air.
HgS + O₂ → Hg + SO₂

(ii) Metals which are in the middle of the series are generally obtained by heating their compounds with some reducing agent such as carbon. For example, iron is obtained from haematite (Fe₂O₃) by reduction with carbon.
2Fe₂O₃ + 3C → 4Fe + 3CO₂

(iii) Metals which are high up in the series are obtained by electrolytic reduction. For example, sodium is obtained by electrolysis of molten sodium chloride.

Question 10.
How is the method of extraction of metals high up in the reactivity series different from that for metal in the middle? Why the same process cannot be applied for them? Explain giving equations, the extraction of sodium.
Answer:
The metals placed high up in the reactivity series (e.g., Na, K, Ca, Mg, Al) are highly reactive and strong reducing agents and are extracted by carrying out the electro-reduction of their molten salts. On the other hand, metals placed in the middle of the series (e.g., Fe, Zn, Cd, Co, Ni, etc.) are comparatively less reactive and are extracted by roasting or calcination.

Sodium is extracted by electro-reduction process.
NaCl ⇌ Na⁺ + Cl^–
Reaction at the cathode: Na⁺ + e⁺ → Na⁺
Reaction at the anode: Cl^– – e^– → Cl
Cl + Cl → Cl₂

Question 11.
Write balanced chemical equation for the reactions taking place when
(i) zinc carbonate is calcinated.
(ii) zinc sulphide is roasted or heated in air.
(iii) zinc oxide is reduced to zinc.
Answer:

Extra Questions for Class 10 Science Chapter 3 Long Answer Type

Question 1.
Explain the following:
(a) Reactivity of Al decreases if it is dipped in HNO₃.
(b) Carbon cannot reduce the oxides of Na or Mg.
(c) NaCl is not a conductor of electricity in solid state whereas it does conduct electricity in aqueous solution as well as in molten state.
(d) Iron articles are galvanised.
(e) Metals like Na, K, Ca and Mg are never found in their free state in nature.   [NCERT Exemplar]
Answer:
(a) On dipping in HNO₃, the surface of Al is oxidised to form an oxide layer of Al₂O₃, which is hard and impervious. It acts as a protective layer for Al underneath. Hence, reactivity of Al decreases.

(b) Na or Mg are highly reactive metals. They have greater affinity for oxygen than for carbon. Hence, their oxides are stable. To reduce them with carbon, very high temperature is required. At this temperature, these metals react with carbon to form corresponding carbides.

(c) The conduction of electricity is due to movement of ions. In the solid state, Na⁺ and Cl^– are fixed and not free to move. Hence, it does not conduct electricity. In the aqueous solution or in the molten state, Na⁺ and Cl^– ions are free to move about and hence conduct electricity.

(d) Galvanisation means coating of iron articles with a layer of zinc. Zinc is more reactive than iron. Hence, it undergoes oxidation more readily than iron. As a result, iron articles remain protected.

(e) These metals are highly reactive and react with the gases present in the air. Hence, they are found as compounds in the ores and not in the free state in nature.

Question 2.
(i) Given below are the steps for extraction of copper from its ore. Write the reaction involved.
(a) Roasting of copper (I) sulphide.
(b) Reduction of copper (I) oxide with copper (I) sulphide.
(c) Electrolytic refining.
(ii) Draw a neat and well labelled diagram for electrolytic refining of copper.   [NCERT Exemplar]
Answer:
(i)

This reaction in which one of the reactants (Cu₂S) carries the reduction of the product (Cu₂O) is known as auto-reduction.

(c) Reaction taking place in electrolytic refining are:
At cathode (reduction): Cu²⁺(aq) + 2e^– → Cu(s)
At anode (oxidation): Cu(s) → Cu²⁺ (aq) + 2e^–

(ii) Metals like copper, aluminium and zinc are refined by this process.

Question 3.
(a) In the formation of compound between two atoms A and B, A loses two electrons and B gains one electron.
(i) What is the nature of the bond between A and B?
(ii) Suggest the formula of the compound formed between A and B.
(b) On similar lines explain the formation of MgCl₂ molecule.
(c) Common salt conducts electricity only in the molten state. Why?
(d) Why is melting point of NaCl high?
Answer:
(a) (i) Ionic bond

(b) Mg → Mg²⁺ + 2e^–
2Cl + 2e^– → 2Cl^–

(c) Na⁺ and Cl^– ions are free to move in molten state but not in solid state.

(d) It is due to strong force of attraction between Na⁺ and Cl^–.

Question 4.
Two ores A and B were taken. On heating ore A gives CO₂ whereas, ore B gives SO₂. What steps will you take to convert them into metals?  [NCERT Exemplar]
Answer:
Since ore A gives CO₂ and ore B gives SO₂. Therefore, ores are MCO₃ and MS.
A can be obtained

B can be obtained

Metals and Non-metals HOTS Questions With Answers

Question 1.
An element A burns with a golden yellow flame in air. It reacts with another element B,
atomic number 17 to give a product C. An aqueous solution of product C on electrolysis gives a compound D and liberates hydrogen. Identify A, B, C and D. Also write down the equations for the reactions involved.  [NCERT Exemplar]
Answer:
A = Sodium which burns with golden flame in air. It reacts with chlorine (Z = 17) to form sodium chloride.
2Na (s) + Cl₂ (g) → 2NaCl (s)

Hence, B = chlorine and C = sodium chloride

Hence, D = Sodium hydroxide.

Question 2.
What is meant by reactivity series of metals? State which of the following chemical reactions will take place giving suitable reason for each.
I. Zn (s) + CuSO₄ (aq) → ZnSO₄ (aq) + Cu (s)
II. Fe (s) + ZnSO₄ (ag) → FeSO₄ (aq) + Zn (s)
III. Zn (s) + FeSO₄ (aq) → ZnSO₄ (aq) + Fe (s)
Answer:
Reactivity series is a list of metals arranged in the order of their decreasing reactivities (activities).
I. Reaction will take place because Zn is above Cu in the activity series and is more reactive than Cu.
II. Reaction will not take place as Fe is below Zn in the activity series and cannot displace Zn from its solution.
III. Reaction will take place because Zn is more reactive than Fe.

Question 3.
A student has been collecting silver coins and copper coins. One day, she observed a black coating on silver coins and a green coating on copper coins. Which chemical phenomenon is responsible for these coatings? Write the chemical name of black and green coatings.
Answer:
The name of the phenomenon is corrosion. The chemical name of black coating is silver sulphide (Ag₂S) formed due to attack of H₂S gas present in the atmosphere on silver and that of green coating is basic copper carbonate formed due to attack of moist air (CO₂, O₂ and H₂O vapours) on copper.

Question 4.
Iqbal treated a lustrous, divalent element M with sodium hydroxide. He observed the formation of bubbles in the reaction mixture. He made the same observations when this element was treated with hydrochloric acid. Suggest how can he identify the produced gas. Write chemical equations for both the reactions.    [NCERT Exemplar]
Answer:
The divalent element M is a metal. It reacts with both sodium hydroxide (alkali) and dilute hydrochloric acid to evolve hydrogen gas.
M(s) + 2NaOH (aq) → Na₂MO₂ (aq) + H₂(g)
M(s) + 2HCl (aq) → MCl₂ (aq) + H₂(g)
The gas burns with a pop sound when a burning matchstick is brought near it.

Question 5.
A non-metal A which is the largest constituent of air, when heated with H₂ in 1: 3 ratio in the presence of catalyst (Fe) gives a gas B. On heating with O₂ it gives an oxide C. If this oxide is passed into water in the presence of air it gives an acid D which acts as a strong oxidising agent.
(a) Identify A, B, C and D.
(b) To which group of periodic table does this non-metal belong?  [NCERT Exemplar]
Answer:
Non-metal which is the largest constituent of air is nitrogen (N₂). Hence, A = N₂.
When heated with H2 in presence of Fe as catalyst, it forms ammonia (NH₃).

Hence, B = NH₃.
When heated with O₂, it forms nitric oxide (NO).

NO further gets oxidised to NO2 by O2 of the air.
2NO(g) + O₂(g) → 2NO₂(g)
Hence, C = NO₂.

On passing this oxide into water in presence of air (O₂), it gives nitric acid (HNO₃) which is a strong oxidising agent.
4NO₂(g) + 2H₂O(l) + O₂(g) → 4HNO₃(aq)
Hence, D = HNO₃.
Nitrogen belongs to Group 15.

Extra Questions for Class 10 Science Chapter 3 Value Based

Question 1.
Anil and his neighbour Sunil had got their garden fenced with iron rods. Next day Anil saw that Sunil was painting the iron fence. Sunil suggested Anil to do the same to increase the longevity of the iron rods by preventing corrosion. Anil argued that it is a waste of time and his iron rods were strong enough. After reading the above passage, answer the following questions.
(i) Whose opinion was correct? Justify.
(ii) Mention two methods (other than painting) to prevent iron from corrosion.
(iii) What is the chemical formula of rust?
(iv) Mention the values exhibited by Sunil.
Answer:
(i) Sunil’s opinion is correct, it helps to protect iron rods from rusting/corrosion.
(ii) (a) Galvanisation
(b) Cathodic protection
(iii) Fe₂O₃. xH₂O
(iv) Friendship/use of knowledge of Chemistry

Question 2.
Mohan approached a goldsmith and asked him to make some gold ornaments. For this he gave advance money also and demanded that 100% pure gold ornaments be made. The goldsmith suggested Mohan that 22-carat gold ornaments would be more appropriate than 24-carat.
(i) What is the difference between 24-carat gold and 22-carat gold?
(ii) Calculate the % of gold in 22-carat gold.
(iii) Why did the goldsmith suggested for use of 22-carat gold?
(iv) Mention the values exhibited by the goldsmith.
Answer:
(i) 24-carat gold is pure gold (100% pure gold) while 22-carat gold is comparatively less pure.
(ii) % of gold in 22 carat = 100 = 91.7%
(iii) Pure of 24-carat gold is very soft, little malleable and ductile. It is quite difficult to work on it. But 22 carat gold (alloy) is comparatively hard, more malleable and ductile.
(iv) Use of knowledge of chemistry, truth, honesty and professionalism.

In this page, we are providing Acids, Bases and Salts Class 10 Extra Questions and Answers Science Chapter 2 pdf download. NCERT Extra Questions for Class 10 Science Chapter 2 Acids, Bases and Salts with Answers will help to score more marks in your CBSE Board Exams. https://ncertmcq.com/extra-questions-for-class-10-science/

Class 10 Science Chapter 2 Extra Questions and Answers Acids, Bases and Salts

Extra Questions for Class 10 Science Chapter 2 Acids, Bases and Salts with Answers Solutions

Extra Questions for Class 10 Science Chapter 2 Very Short Answer Type

Class 10 Science Chapter 2 Extra Questions Question 1.
Write a balanced chemical equation for the reaction between sodium carbonate and hydrochloric acid indicating the physical state of the reactants and products.   [Foreign 2010]
Answer:
Na₂CO₃ (s) + 2HCl (ag) → 2NaCl (aq) + CO₂ (g) + H₂O (l)

Acids Bases And Salts Class 10 Extra Questions Question 2.
During summer season, a milkman usually adds a small amount of baking soda to fresh milk. Give reason.   [CBSE Sample Paper 2009]
Answer:
A milkman adds a very small amount of baking soda so as to prevent spoilage of milk. It leads to change in the pH which does not allow bacteria and enzymes to act and milk does not become sour due to fermentation.

Acid Bases And Salts Class 10 Extra Questions Question 3.
What is the difference between slaked lime and lime water?  [CBSE 2010]
Answer:
A suspension of Ca(OH)₂ in water is called slaked lime. Water containing traces of Ca(OH)₂ is called lime water.

Chapter 2 Science Class 10 Extra Questions Question 4.
Which acid is present in sour milk or curd?
Answer:
Lactic acid.

Acids Bases And Salts Extra Questions Question 5.
Why is potassium iodide added into common salt to use it as table salt?
Answer:
The iodide present in the salt prevents thyroid disorders.

Extra Questions For Class 10 Science Chapter 2 Question 6.
What are the pH values of distilled water and common salt solution?  [CBSE 2010]
Answer:
Both are neutral and have pH close to 7.

Ch 2 Science Class 10 Extra Questions Question 7.
A dry pellet of a common base B, when kept in open absorbs moisture and turns sticky. The compound is also a by-product of chloralkali process. Identify B. What type of reaction occurs when B is treated with an acidic oxide? Write a balanced chemical equation for one such solution.  [NCERT Exemplar]
Answer:
Dry pellets of sodium hydroxide absorb moisture and turn sticky when kept in open which is also a by-product of chloralkali process.

When sodium hydroxide is treated with an acidic oxide it produces salt and water.

Acid Bases And Salts Extra Questions Question 8.
Which bases are called alkalies? Give an example of an alkali. [CBSE 2009, 2010]
Answer:
Soluble bases are called alkalies. For example, sodium hydroxide (NaOH).

Class 10 Chemistry Chapter 2 Extra Questions Question 9.
A knife, which is used to cut a fruit, was immediately dipped into water containing drops of blue litmus solution. If the colour of the solution is changed to red, what inference can be drawn about the nature of the fruit and why? [CBSE 2011]
Answer:
Since the colour of the blue litmus has changed to red, this means that the fruit juice is acidic in nature.

Acid Base And Salt Extra Question Answer Question 10.
How do H⁺ ions exist in water?
Answer:
H⁺ ions in water combine with water (H₂O) molecules and exist as H₃O⁺ ion, called hydronium ion.

Class 10 Science Ch 2 Extra Questions Question 11.
What should be done as remedy if stung by leaves of nettle plant in the wild?
Answer:
The area should be rubbed with the leaf of dock plant.

Extra Questions Of Acids Bases And Salts Class 10 Question 12.
What happens when nitric acid is added to egg shell?  [NCERT Exemplar]
Answer:
Egg shell is made of calcium carbonate. When nitric acid is added to egg shell calcium nitrate, carbon dioxide and water are formed.
CaCO₃ + 2HNO₃ → Ca(NO₃)₂ + CO₂ + H₂O

Acid Base And Salts Class 10 Extra Questions Question 13.
What is the concentration of H⁺ ion in pure water?
Answer:
10^-7

Ncert Class 10 Science Chapter 2 Extra Questions Question 14.
Which one of these has a higher concentration of H⁺ ions? 1 M HCl or 1 M CH₃COOH.   [CBSE 2009]
Answer:
1 M HCl has higher concentration of H⁺ ions.

Class 10 Chapter 2 Science Extra Questions Question 15.
Name an example of olfactory indicators.
Answer:
Vanilla.

Question 16.
Name the chemical substance present in thick white and yellowish clouds present in the atmosphere of Venus.
Answer:
Sulphuric acid.

Question 17.
What is acid rain?
Answer:
Rainwater having pH less than 5.6, is called acid rain.

Question 18.
Name the hardest substance in the body.
Answer:
Tooth enamel (Calcium phosphate).

Question 19.
The pH of three solutions A, B and C are 4, 9 and 6 respectively. Arrange them in increasing order of acidic strength. [CBSE 2010]
Answer:
The increasing order of acidic strength is : B < C < A.

Question 20.
Name the chemist who had given the pH scale.
Answer:
S.P.L. Sorensen (1909).

Question 21.
Name the acid present in tomato.
Answer:
Oxalic acid.

Question 22.
Acidic and basic solutions in water conduct electricity. Why?
Answer:
Because they produce hydrogen and hydroxide ions respectively.

Question 23.
What would be the colour of litmus in a solution of sodium carbonate?   [CBSE 2009]
Answer:
Red litmus will change to blue in sodium carbonate solution.

Question 24.
The pH of a sample of vegetable soup was found to be 6.5. How is this soup likely to taste?
Answer:
The taste will be slightly sour as it is weakly acidic.

Question 25.
Name the chemical substance which is used in the manufacture of soap as well as used as a preservative in pickles.
Answer:
Sodium chloride (NaCl).

Question 26.
There are two jars A and B containing food materials. Food in jar ‘A’ is pickled with acetic acid while ‘B’ is not. Food of which of jar will stale first? Explain. Name two synthetic indicators which are used to test acids and bases.
Answer:
Food in jar ‘B’ will stale first because it will undergo oxidation and will also be attacked by microorganisms.
Synthetic indicators: Phenolphthalein, methyl orange.

Question 27.
What is the chemical formula of soda ash?
Answer:
Na₂CO₃

Question 28.
Name the substance used for disinfecting drinking water supply.
Answer:
Bleaching powder.

Question 29.
Name a chemical substance which can be used to detect the presence of moisture in a liquid.
Answer:
Anhydrous copper sulphate.

Question 30.
What is meant by water of crystallisation?
Answer:
Water of crystallisation is the fixed number of water molecules chemically attached to each formula unit of a salt in its crystalline form.

Question 31.
Which one is a stronger acid, with pH = 5 or with pH = 2?
Answer:
The acid with pH = 2 is a stronger acid.

Question 32.
Fresh milk has a pH of 6. When it changes into curd (yogurt), will its pH value increases or decrease? Why?
Answer:
Its pH will decrease because curd (yogurt) is sour in taste due to presence of acid in it.

Extra Questions for Class 10 Science Chapter 2 Short Answer Type I

Question 1.
How would you distinguish between baking powder and washing soda by heating?   [NCERT Exemplar]
Answer:
Baking soda (NaHCO₃) gives carbon dioxide and water vapour on heating at very low temperature. The gas so formed turns lime water milky, which confirms the presence of carbon dioxide gas.

When washing soda (Na₂CO₃) is heated it does not produce carbon dioxide even at high temperatures, but gives off its water of crystallisation to become anhydrous salt.

Question 2.
A sulphate salt of Group 2 element of the Periodic Table is a white, soft substance, which can be moulded into different shapes by making its dough. When this compound is left in the open for some time, it becomes a solid mass and cannot be used for moulding purposes. Identify the sulphate salt and why does it show such a behaviour? Give the reaction involved.   [NCERT Exemplar]
Answer:
Calcium belongs to group 2. Calcium sulphate is a white soft substance. It is known as Plaster of Paris, which can be moulded into different shapes by making its dough.

When Plaster of Paris is left for some time in the open, it turns into a solid mass because of reaction with moisture present in the atmosphere. The solid mass so formed is known as gypsum and cannot be further used for moulding.

The above said group 2 element is calcium sulpahte.

Question 3.
Name the acid present in ant sting and give its chemical formula. Also give the common method to get relief from the discomfort caused by the ant sting.   [NCERT Exemplar]
Answer:
The acid present in ant sting: Methanoic acid
Chemical Formula of methanoic acid: HCOOH
Method to get relief from the discomfort caused by the ant sting: Rubbing baking soda over the area of ant sting.
Explanation: Rubbing baking soda (a base) over ant sting neutralises the methanoic acid present in the ant sting and gives relief from pain.

Question 4.
List two differences between acids and bases on the basis of chemical properties.
Answer:
(i) Dilute acids like HCl and H₂SO₄ evolve H₂ gas on reacting with metals like Zn, Mg and Ca, etc. and dilute bases do not evolve hydrogen gas.
(ii) Acids react with oxides of metals while bases react with oxides of non-metals.

Question 5.
List four main differences between acids and bases.
Answer:

Properties	Acids	Bases
1. Taste	Sour	Bitter
2. Action on litmus paper	They turn blue litmus paper red	They turn red litmus paper blue.
3. Action with phenolphthalein	No action	They turn phenolphthalein pink.
4. Action with carbonates and bicarbonates	They decompose carbonates and bicarbonates to liberate carbon dioxide.	No action

Question 6.
Mention the terms defined by the following sentences:
(a) A soluble base
(b) The insoluble solid formed when two solution are mixed together.
Answer:
(a) Alkali
(b) Precipitate.

Question 7.
Name the product formed in each case when:
(а) hydrochloric acid reacts with caustic soda.
(b) granulated zinc reacts with caustic soda.
Answer:
(a) The product formed is a mixture of sodium chloride and water.
NaOH (ag) + HCl (ag) → NaCl (ag) + H₂O

(b) The product formed is a mixture of sodium zincate and hydrogen gas.
Zn (s) + 2NaOH (ag) → Na₂ZnO₂ (ag) + H₂(g)

Question 8.
Explain why sodium hydroxide solution cannot be kept in aluminium containers? Write equation for the reaction that may take place for the same.
Answer:
Sodium hydroxide solution reacts with aluminium to form sodium metaaluminate and hydrogen is evolved. Therefore, it cannot be kept in a container made of aluminium.

Question 9.
How can you obtain the following gases by using dilute acid and one other substance?
(а) hydrogen
(b) carbon dioxide.
Answer:
(a) Fe + H₂SO₄(dil.) → FeSO₄ + H₂(g)
Mg + 2HCl(dil.) → MgCl₂ + H₂(g)

(b) Na₂CO₃ + 2HCl(dil.) → 2NaCl + H₂O + CO₂(g)
NaHCO₃ + HCl(dil.) → NaCl + H₂O + CO₂(g)

Question 10.
A solution of HCl is taken in a beaker and an electric circuit with a bulb is set up with the solution in series. What happens to the bulb and why?
Answer:
The bulb will start glowing. Glowing of the bulb indicates that there is a flow of electric current through the solution. Electric current is carried through the solution by ions.

Since the cation present in acids is H⁺, this suggests that acids produce hydrogen ions, H⁺(ag), in solution, which are responsible for carrying current through the solution.

Question 11.
If 280 g of washing soda crystals are left in dry air for some time, a loss of weight of 162 g occurs. How can you account for this?
Answer:
Washing soda (Na₂CO₃. 10H₂O) is an efflorescent substance (if exposed to air, it loses most of its water of crystallisation). 280 g of washing soda lose 162 g of its water of crystallisation.

Question 12.
A sample of bleaching powder was kept in an air tight container. After a month, it lost some of its chlorine content. How will you account for it?
Answer:
Bleaching powder if kept even in an air tight container, will slowly decompose on its own and form calcium chlorate and calcium chloride. The reaction is called auto oxidation. This will result in decrease in its chlorine contents.

Question 13.
A compound which is prepared from gypsum has the property of hardening when mixed with proper quantity of water. Identify the compound. Write chemical equation to prepare the compound. Mention one important use of the compound.
Answer:
The compound is Plaster of Paris (CaSO₄. \(\frac { 1 }{ 2 }\) H₂O). It is formed from gypsum (CaSO₄ . \(\frac { 1 }{ 2 }\) H₂O) upon heating to a temperature of 373 K. It changes back to gypsum on adding water. Plaster of Paris is used for setting fractured bones.

Question 14.
A white powder is added while baking breads and cakes to make them soft and fluffy. Write the name of the powder. Name its main ingredients. Explain the function of each ingredient. Write the chemical reaction taking place when the powder is heated during baking.   [CBSE 2012, 2013]
Answer:
The white powder is known as baking powder. The main ingredients are baking soda (NaHCO₃) and tartaric acid (C₄H₆O₆).

Question 15.
Explain giving reasons:
(i) Tartaric acid is a component of baking powder used in making cakes.
(ii) Gypsum (CaSO₄. 2H₂O) is used in the manufacture of cement.
Answer:
(i) Role of tartaric acid in baking powder (mixture of tartaric acid and sodium hydrogencarbonate) is to neutralise sodium carbonate formed upon heating sodium hydrogencarbonate.

In case it is not done, cake will be better and sodium carbonate will also have injurious side effects.

(ii) The role of gypsum (CaSO₄.2H₂O) in the manufacture of cement is to slow down the process of setting of cement.

Extra Questions for Class 10 Science Chapter 2 Short Answer Type II

Question 1.
What will be the action of the following substances on litmus paper?
Dry HCl gas, moistened NH₃ gas, lemon juice, carbonated soft drink, curd, soap solution.  [NCERT Exemplar]
Answer:
Dry HCl gas: No action
Moistened NH₃ gas: Turns red litmus blue.
Lemon juice: Turns blue litmus red.
Carbonated soft drink: Turns blue litmus red.
Curd: Turns blue litmus red.
Soap solution: Turns red litmus blue.

Explanation:

• Dry HCl gas does not liberate hydrogen ion, hence no action takes place with litmus paper.
• NH₃ gas forms ammonium hydroxide with water which turns red litmus paper blue.
• Lemon juice is citric acid, so it turns blue litmus paper red.
• Carbonate soft drink contains carbon dioxide dissolved in water. Carbon dioxide forms carbonic acid with water; which turns blue litmus paper red.
• Curd contains lactic acid and hence turns blue litmus paper red.
• Soap solution is basic in nature hence it turns red litmus paper blue.

Question 2.
When zinc metal is treated with a dilute solution of a strong acid, a gas is evolved, which is utilised in the hydrogenation of oil. Name the gas evolved. Write the chemical equation of the reaction involved and also write a test to detect the gas formed.   [NCERT Exemplar]
Answer:
Zinc metal gives hydrogen gas when it is treated with dilute sulphuric acid. Hydrogen gas is utilised in hydrogenation of oil.
Therefore, the gas evolved is hydrogen.

Test for hydrogen gas: When a burning candle is brought near hydrogen gas, it bums with a pop sound which confirms the presence of hydrogen gas.

Question 3.
(i) Identify the compound of calcium which is a yellowish powder and is used for disinfecting drinking water. Write its chemical name and formulae.
(ii) Write the balanced chemical equation of chlor-alkali process.   [CBSE 2012, 2014]
Answer:
(i) The yellowish white solid is known as bleaching powder. Chemically, it is calcium oxychloride or calcium hypochlorite. Its chemical formula is CaOCl₂.

(ii) Chemical equation for chlor-alkali process is

Question 4.
Explain with suitable reason
(a) Ferric chloride is stored in air tight bottles.
(b) On exposure to atmosphere, Glaublar’s salt loses weight while quicklime gains weight.
(c) Common salt (containing traces of magnesium chloride) becomes sticky during the monsoons.
Answer:
(a) Because ferric chloride is deliquescent in nature.
(b) Glaubar’s salt is efflorescent and loses water of crystallisation whereas quick lime is hygroscopic in nature and absorbs moisture from the air.
(c) This is because magnesium chloride is deliquescent and absorbs moisture from the atmospheric air and becomes moist.

Question 5.
(a) A solution has a pH of 7. Explain how you would
(i) increases its pH
(ii) decrease its pH
(b) If a solution changes the colour of litmus from red to blue, what can you say about its pH?
(c) What can you say about the pH of a solution that liberates CO₂ from sodium carbonate?
Answer:
(a) (i) By adding some alkali like NaOH
(ii) By adding some acid like HCl

(b) Since the solution changes the colour of litmus from red to blue it is alkaline and hence it has pH > 7.

(c) Since the solution liberates CO₂ from sodium carbonate, it should be acidic and has pH < 7.

Question 6.
A compound which is prepared from gypsum has the property of hardening when mixed with proper quantity of water.
(i) Identify the compound.
(ii) Write the chemical equation for its preparation.
(iii) Mention one important use of this compound.
Answer:
(i) Plaster of Paris

(iii) It is used for plastering fractured bones.

Question 7.
Write any three chemical properties of acids.
Answer:
(i) They react with metals to give out hydrogen gas, for example,

(ii) They react with bases to form salt and water, for example,

(iii) They react with metal carbonates to liberate carbon dioxide gas.

Question 8.
Classify the solutions of the following as acids, bases and salts:
Ammonium hydroxide, barium chloride, sodium chloride, sodium hydroxide, sulphuric acid and nitric acid.
Answer:

Acids	Bases	Salts
1. Sulphuric acid	Ammonium hydroxide	Barium chloride
2. Nitric acid	Sodium hydroxide	Sodium chloride

Question 9.
You are given two solutions A and B. The pH of solution A is 6 and pH of solution B is 8.
(i) Which solution is acidic and which is basic?
(ii) Which solution has more H+ ion concentration?
(iii) Why is HCl a stronger acid than acetic acid?   [CBSE 2011]
Answer:
(i) The solution with pH 6 is acidic while the solution with pH 8 is basic.
(ii) The solution with pH 6 has more H⁺ ion concentration.
(iii) HCl is a stronger acid than CH₃COOH since its degree of dissociation (α) is more or it releases more H+ ions in solution than acetic acid.

Question 10.
What is tooth enamel chemically? State the conditions when it starts corroding. What happens when food particles left in the mouth after eating degrade? Why do doctors suggest use of powder/tooth paste to prevent tooth decay? [CBSE 20011, 2014]
Answer:
(i) The tooth enamel is chemically calcium phosphate with the formula Ca₃(PO₄)₂. It is quite hard.
(ii) The enamel starts corroding when the pH inside our mouth falls below 5.5 because the saliva present in the mouth becomes acidic.
(iii) The bacteria present in the mouth breakdown the food particles into acids which damage our teeth by corroding them.
(iv) The contents of the tooth paste are of basic nature. They neutralise the excess acid present. As a result, the corrosion of enamel and decay of teeth are checked.

Question 11.
(a) Write the name given to bases that are highly soluble in water. Give an example.
(b) How is tooth decay related to pH? How can it be prevented?
(c) Why does bee sting cause pain and irritation? Rubbing of baking soda on the sting area gives relief. How?
Answer:
(a) Alkali, for example, NaOH (Sodium hydroxide).

(b) Lower the pH, more will be tooth decay. Acid formed in the mouth reacts with enamel which is made up of [Ca₃(PO₄)₂] and causes tooth decay.
It can be prevented by brushing our teeth after every meal.

(c) A bee injects formic acid into the skin when it stings which causes pain and irritation. Sodium hydrogencarbonate (baking soda) neutralises formic acid giving relief.

Question 12.
Mention the colour changes observed when the following indicators are added to acids:
(i) Alkaline phenolphthalein solution
(ii) Methyl orange solution
(iii) Neutral litmus solution
Answer:
(i) It gets decolourised
(ii) It turns red or pink
(iii) It turns red.

Question 13.
Choosing only substances from the list given in the box below, write equations for the reactions which you would use in the laboratory to obtain:
(a) Sodium sulphate
(b) Iron (II) sulphate
(c) Zinc carbonate.
Dilute sulphuric acid, copper, iron, copper carbonate, sodium, zinc, sodium carbonate
Answer:
(a) Sodium sulphate
Na₂CO₃ + H₂SO₄ (dil.) → Na₂SO₄ + H₂O + CO₂ (g)

(b) Iron (II) sulphate
Pe + H₂SO₄ (dil.) → FeSO₄ + H₂ (g)

(c) Zinc carbonate
Zn + CuCO₃ → ZnCO₃ + Cu

Question 14.
What is dilution? What precaution should be taken during dilution of a strong acid like sulphuric acid?
Answer:
Dilution is a process in which concentration of a substance decreases by addition of a solvent. Care must be taken while mixing concentrated sulphuric acid with water as the process is a highly exothermic one. The acid must always be added slowly to water with constant stirring. If water is added to a concentrated acid, the heat generated may cause the mixture to splash out and cause burns. The glass container may also break due to excessive local heating.

Question 15.
Write balanced equations to satisfy each statement:
(a) Acid + Chloride → Salt + Hydrochloric acid gas
(b) Acid + Carbonate → Salt + Water + Carbon dioxide
(c) Acid + Sulphite → Salt + Water + Sulphur dioxide
Answer:
(a) H₂SO₄ + NaCl → NaHSO₄ + HCl (g)
(b) 2HCl + Na₂CO₃ → 2NaCl + H₂O + CO₂ (g)
(c) 2HCl + CaSO₃ → CaCl₂ + H₂O + SO₂ (g)

Extra Questions for Class 10 Science Chapter 2 Long Answer Type

Question 1.
What are strong and weak acids? In the following list of acids, separate strong acids from weak acids.  [NCERT Exemplar]
Hydrochloric acid, citric acid, acetic acid, nitric acid, formic acid, sulphuric acid.
Answer:
Strong acid: Strong acids ionise completely in their aqueous solutions to produce a large number of hydrogen ions. Mineral acids are generally strong acids.

Weak acid: Weak acids do not ionise completely in their aqueous solution. Organic acids are generally weak acids.

Strong acid: Hydrochloric acid, nitric acid, sulphuric acid
Weak acid: Citric acid, acetic acid, formic acid

Question 2.
(i) Explain, why is hydrochloric acid a strong acid and acetic acid, a weak acid? How can it be verified?
(ii) Explain, why aqueous solution of an acid conducts electricity?
(iii) You have four solutions A, B, C and D. The pH of solution A is 6, B is 9, C is 12 and D is 7.
(a) Identify the most acidic and most basic solutions.
(b) Arrange the above four solutions in the increasing order of H+ ion concentration.
(c) State the change in colour of pH paper on dipping in solution C and D.   [CBSE 2012, 2013]
Answer:
(i) Hydrochloric acid (HCl) is a stronger acid than acetic acid (CH₃COOH) because it dissociates completely into H⁺ and Cl^– ions in aqueous solution. In order to verify this, add a few drops of universal indicator solution in the test tubes containing the acids. It acquires red colour in hydrochloric acid and yellow in acetic acid which confirms that hydrochloric acid is a stronger acid.

(ii) An aqueous solution of an acid releases ions in aqueous solutions. These ions conduct electricity.

(iii) (a) Most acidic is A (pH = 6) and most basic is C (pH = 12).
(b) The increasing order of H⁺ ion concentration is : C < B < D < A.
(c) The pH paper acquires dark purple colour in solution C and green in solution D.

Question 3.
Fill the missing data in the following table:

Answer:

Question 4.
(a) Explain how antacids give relief from acidity. Write the name of one such antacid.
(b) Fresh milk has a pH of 6. How does the pH change as it turns to curd? Explain your answer.
(c) A milkman adds a very small amount of baking soda to fresh milk. Why does this milk take a longer time to set as curd?
(d) Mention the nature of toothpastes. How do they prevent tooth decay?
Answer:
(a) Our stomach produces hydrochloric acid that helps in digestion of food. During indigestion, our stomach produces excess acid. Antacids neutralise the excess of acid produced and gives relief from hyperacidity. Milk of magnesia (magnesium hydroxide) is one of such antacid.

(b) pH will decrease as it turns to curd because curd is acidic due to the presence of lactic acid.

(c) It takes longer time to set as curd as the presence of baking soda (sodium hydrogen carbonate) makes the milk basic and it does not allow it to become acidic easily.

(d) Toothpastes are basic in nature. They neutralise the acid formed in mouth which causes tooth decay.

Question 5.
(a) Explain the following chemical properties of acids with the help of balanced chemical equations only.
(i) when an acid reacts with a metal carbonate
(ii) when an acid reacts with a metal bicarbonate
(iii) when an acid reacts with a metal oxide.
(b) You are given three solutions A, B and C with pH values 2, 10 and 13 respectively. Write which solution has more hydrogen ion concentration among the three and state the nature ‘acidic or basic’ of each solution.
Answer:
(a) (i) CaCO₃ + 2HCl → CaCl₂ + H₂O + CO₂
(ii) NaHCO₃ + HCl → NaCl + H₂O + CO₂
(iii) Al₂O₃ + 6HCl → 2AlCl₃ + 3H₂O

(b) ‘A’ has maximum [H₃O⁺] equal 10^-2 mol L^-1
‘A’ acidic whereas B and C are basic in nature.

Question 6.
Complete the following reaction:
(i) 2NaCl (aq) + 2H₂O(l) →
(ii) Ca(OH)₂ + Cl₂ →
(iii) NaCl + H₂O + CO₂ + NH₃ →
(iv)
(v) Na₂CO₃ + 10H₂O
Answer:
(i) 2NaCl(aq) + 2H₂O(l) → 2NaOH(aq) + Cl₂(g) + H₂(g)
(ii) Ca(OH)₂ + Cl₂ → CaOCl₂ + H₂O

Acids Bases and Salts HOTS Questions With Answers

Question 1.
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 was not available in the laboratory. Since both the solutions were colourless, how would she distinguish between the two?  [NCERT Exemplar]
Answer:
While answering this question, we need to make certain assumptions. Let us assume that laboratory has all the necessary items but no litmus paper. We can use phenolphthalein to check which of the beakers contains acid and which one contains a base. Apart from that, we can also use other natural indicators; like China rose or turmeric.

Question 2.
Salt A commonly used in bakery products on heating gets converted into another salt B which itself is used for removal of hardness of water and a gas C is evolved. The gas C when passed through lime water, turns it milky. Identify A, B and C.  [NCERT Exemplar]
Answer:
Baking powder which is a salt used in bakery products. It give sodium carbonate and carbon dioxide gas on heating. Sodium carbonate is used to remove hardness of water. Carbon dioxide turns lime water milky.

Therefore,

• Salt A, which is sodium bicarbonate and used as baking powder.
• Salt B is sodium carbonate, which is used to remove hardness of water.
• The C is carbon dioxicje gas which turns lime water milky.

Question 3.
In one of the industrial processes used for manufacture of sodium hydroxide, a gas X is formed as by product. The gas X reacts with lime water to give a compound Y which is used as bleaching agent in chemical industry. Identify X and Y giving the chemical equation of the reactions involved.   [NCERT Exemplar]
Answer:
Sodium chloride is used in the manufacture of sodium hydroxide by the Chlor-Alkali process. In this process chlorine and hydrogen gas are formed as by products along with sodium hydroxide. Chlorine gas reacts with lime water to produce bleaching power which is used as bleaching agent in chemical industries.

Therefore,

• The gas ‘X’ is chlorine.
• Compound Y is calcium oxychloride which is commonly known as bleaching powder and used as bleaching agent in chemical industries.

Question 4.
In the following schematic diagram for the preparation of hydrogen gas as shown in Figure. What would happen if following changes are made?   [NCERT Exemplar]
Answer:

(a) In place of zinc granules, same amount of zinc dust is taken in the test tube.
(b) Instead of dilute sulphuric acid, dilute hydrochloric acid is taken.
(c) In place of zinc, copper turnings are taken.
(d) Sodium hydroxide is taken in place of dilute sulphuric acid and the tube is heated.
Answer:
(a) When zinc dust is taken instead of zinc granules to react with sulphuric acid, hydrogen gas is formed. But the rate of reaction increases in the case of zinc dust compared to zinc granules, because of increased surface area of zinc dust which increases the rate of reaction.

Thus, when zinc dust is used in the place of zinc granules, hydrogen gas is produced at a faster rate.

(b) Zinc granules give hydrogen gas; along with zinc chloride; when they react with hydrochloric acid.

Thus, when hydrochloric acid is used in place of sulphuric acid, zinc chloride is formed instead of zinc sulphate; along with hydrogen gas and the reaction takes place at the same rate.

(c) Copper does not react with dilute acids under normal conditions because copper lies at lower position in the reactivity series and does not displace hydrogen from dilute acids.
Thus, if copper turnings are taken in place of zinc granules, no reaction will take place.

(d) If sodium hydroxide is taken in place of dilute sulphuric acid and the tube is heated, sodium zincate is formed along with hydrogen gas. Heating the test tube will increase the rate of formation of hydrogen gas as heating the reaction mixture increases the rate of reaction.

Question 5.
Identify the compound X on the basis of the reactions given below. Also, write the name and chemical formulae of A, B and C.   [NCERT Exemplar]
Answer:

Answer:

Therefore,

• Compound “X’ is sodium hydroxide (NaOH).
• Compound ‘A’ is zinc sulphate (ZnSO₄).
• Compound ‘B’ is sodium chloride (NaCl).
• Compound ‘C’ is sodium acetate (CH₃COONa).

Question 6.
A metal carbonate X on reacting with an acid gives a gas which when passed through a solution Y gives the carbonate back. On the other hand, a gas G that is obtained at the anode during electrolysis of brine is passed on dry Y, it gives a compound Z, used for disinfecting drinking water. Identity X, Y, G and Z.   [NCERT Exemplar]
Answer:
Calcium carbonate gives carbon dioxide gas when it reacts with hydrochloric acid.

Carbon dioxide turns lime water milky when passed through it because of formation of calcium carbonate. When carbon dioxide; so formed; is passed through lime water, it turns milky because of the formation of calcium carbonate.

On electrolysis of brine, chlorine gas is produced at the anode. Therefore G is Cl₂.
Bleaching powder is used in disinfecting drinking water.
Therefore Z can be CaOCl₂.
When chlorine is passed through dry calcium hydroxide [Ca(OH)₂], bleaching powder CaOCl₂ is formed.

Therefore, Y is calcium hydroxide, Ca(OH)₂.
Since Y reacts with a gas to give a carbonate, the gas is CO₂ and the carbonate is CaCO₃.

Therefore, the metal carbonate X is calcium carbonate, CaCO₃.
Therefore,

• Metal carbonate ‘X’ is calcium carbonate.
• Solution ‘Y is lime water (Calcium hydroxide).
• Gas ‘G’ is chlorine gas.
• Dry Y’ is dry calcium hydroxide (dry slaked lime).
• Compound ‘Z’ is bleaching powder (Calcium oxychloride).

Question 7.
A substance X used as an antacid reacts with hydrochloric acid to produce a gas Y which is used in extinguishers.
(а) Name the substances X and Y.
(b) Write a balanced equation of the reaction between X and hydrochloric acid.   [CBSE 2011]
Answer:
(a) Substance X is sodium hydrogencarbonate (X) and the gas evolved Y is carbon dioxide.
(b)

Question 8.
You are provided with the following materials in your laboratory:
Answer:
Hydrochloric acid (HCl), sulphuric acid, (H₂SO₄), nitric acid (HNO₃), acetic acid (CH₃COOH), sodium hydroxide (NaOH), potassium hydroxide (KOH), calcium hydroxide [Ca(OH)₂], magnesium hydroxide [Mg(OH)₃] and ammonium hydroxide (NH₄OH).
If we test each of the above solutions one by one with a drop of the following indicators, what colour change will you observe?
Red litmus, blue litmus, phenophthalein, methyl orange.
Answer:
Acidic substances: HCl, H₂SO₄, HNO₃, CH₃COOH
They will turn blue litmus red and methyl orange red. There will be no effect on red litmus and phenolphthalein.

Basic substances: NaOH, KOH, Ca(OH)₂, Mg(OH)₂, NH₄OH. They will turn red litmus blue and phenolphthalein pink. There will be no effect on blue litmus and methyl orange.

Question 9.
The crystals of a compound A on keeping in air get converted into a white powder. Its solution in water gives blue colour with red litmus. It is used to remove permanent hardness from water.
(a) Identify the substance. Write chemical formula for its crystalline form.
(b) From the given information, identify the nature of the substance.
(c) Write two more uses of the substance.   [CBSE 2013]
Answer:
(a) The substance is washing soda. Its chemical formula is Na₂CO₃.10H₂O.
(b) Since the aqueous solution of the substance in water turns red litmus blue, it is of basic nature.
(c) (i) It is used in laundry for washing clothes.
(ii) It is used in the manufacture of glass, paper and chemicals like caustic soda (NaOH), and borax (Na₂B₄O₇), etc.

Question 10.
A substance X is used as a building material and is insoluble in water. When reacted with dilute HCl, it produces a gas which turns lime water milky. Predict the substance. Write the chemical equations evolved.
Answer:
The substance is probably calcium carbonate (CaCO₃), also called lime stone or marble. It is used as a building material. On reacting with dilute HCl, it evolves CO₂ gas which turns lime water milky.

Question 11.
When electricity is passed through a common salt solution, sodium hydroxide is produced along with the liberation of two gases ‘X’ and T. The gas ‘X’ burns with a pop sound whereas T is used for disinfecting drinking water.  [CBSE 2011]
(i) Identify X and Y.
(ii) Give the chemical equation for the reaction stated above.
(iii) State the reaction of Y with dry slaked lime.
Answer:
(i) The gas X’ is H₂ and gas ‘Y’ is Cl₂.
(ii) The chemical equation for the reaction is:

(iii) Cl₂ reacts with slaked lime to form bleaching powder.
Ca(OH)₂ + Cl₂ → CaOCl₂ + H₂O

Extra Questions for Class 10 Science Chapter 2 Value Based

Question 1.
Aman is fond of eating fast foods and chat. He was suffering from a stomach pain and indigestion for a number of days. Doctor advised him to take antacid tablet after each meal and avoid spicy and junk food. He followed the advice and was cured rapidly.
(i) What is an antacid?
(ii) How are antacid tablets helpful in such indigestion? Justify by the relevant chemical reaction.
(iii) Mention the values exhibited by Aman and the doctor.
Answer:
(i) Antacid is a substance which can neutralise acidity in the stomach.
(ii) The antacid tablets or gels contain base like NaHCO₃ or Mg(OH)₂ which neutralise the effect of excess HCl released in the stomach as
NaHCO₃ + HCl → NaCl + H₂O + CO₂
(iii) Knowledge of Chemistry, caring.

Question 2.
Ayush has cold drinks, chocolates and sweets every day. His teeth were getting damaged. His science teacher asked him to brush his teeth after every meal as well as after eating sweets.
(i) How do the teeth get damaged due to eating chocolates and sweets?
(ii) Brushing of teeth is helpful and prevent tooth decay. Justify.
(iii) Mention the values exhibited by the science teacher.
Answer:
(i) On eating sweets/chocolates the pH of mouth becomes less than 5.5, so tooth enamel gets corroded and tooth decay starts.
(ii) Using toothpaste, which is basic in nature can neutralise the excess acid formed in the mouth and prevent tooth decay.
(iii) Caring, helpful nature, knowledge of Chemistry.

Question 3.
Mohan and Priyanka were playing in the garden. Priyanka was stung by a bee and started crying and returned home. Her mother immediately observed the affected area and applied a thin coating of toothpaste as first aid, then took her to the nearest doctor.
(i) Why did Priyanka cry?
(ii) Name the chemical substance present in bee sting.
(iii) How is toothpaste effective in such incident?
(iv) Mention the values exhibited by Priyanka’s mother.
Answer:
(i) Priyanka cried because the bee injected an acid while stinging which caused pain and irritation.
(ii) Formic acid or Methanoic acid (HCOOH)
(iii) Toothpaste is basic in nature so it neutralise the effect of formic acid and gives relief.
(iv) Knowledge of Chemistry, caring nature.

Question 4.
Manshi is a student of class X in a city school. There was a tall tree at the edge of the garden having a large honeycomb attached to it. Some students were playing cricket in the school playground. Suddenly the cricket ball hit the honeycomb due to which a large number of honey-bees started flying here and there. Manshi was stung on her face by a honey-bee. The sting was so painful that Manshi started crying. One of her classmates Shanti quickly got some baking soda and made a paste of it with water. Then she applied the paste on the stung area of the face. On rubbing baking soda solution, Manshi felt a lot of relief from the pain.
(a) What kind of liquid is injected into the skin when honey-bee strings?
(b) Why did rubbing baking soda solution on the stung area of skin give relief from pain?
(c) What type of chemical reaction takes place when baking soda solution is rubbed on the area stung by honey-bee?
(d) What values are exhibited by Shanti and the classmates?
Answer:
(а) Honey-bee sting injects an acidic liquid into the skin.

(b) Baking soda is a mild base. Being a base, baking soda solution neutralises the acidic liquid injected by honey-bee sting and neutralises its effect. This gives relief from pain.

(c) Neutralisation reaction (between an acid and a base)

(d) The values displayed by Shanti and classmates are

• Awareness
• Knowledge of Chemistry and
• Desire to remove the suffering of others.

Here we are providing Introduction to Trigonometry Class 10 Extra Questions Maths Chapter 8 with Answers Solutions, Extra Questions for Class 10 Maths was designed by subject expert teachers. https://ncertmcq.com/extra-questions-for-class-10-maths/

Extra Questions for Class 10 Maths Introduction to Trigonometry with Answers Solutions

Extra Questions for Class 10 Maths Chapter 8 Introduction to Trigonometry with Solutions Answers

Introduction to Trigonometry Class 10 Extra Questions Short Answer Type 1

Trigonometry Class 10 Extra Questions Question 1.
Find maximum value of \(\frac{1}{\sec \theta}\), 0°≤ θ ≤ 90°.
Solution:
\(\frac{1}{\sec \theta}\), (0° ≤ θ ≤ 90°) (Given)
∵ sec θ is in the denominator
∴ The min. value of sec θ will return max. value for \(\frac{1}{\sec \theta}\).
But the min. value of sec θ is sec 0° = 1.
Hence, the max. value of \(\frac{1}{\sec 0^{\circ}}\) = \(\frac{1}{1}\) = 1

Trigonometry Extra Questions Class 10 Question 2.
Given that sin θ = \(\frac{a}{b}\), find the value of tan θ.
Solution:
sin θ = \(\frac{a}{b}\)

Trigonometry Questions For Class 10 Question 3.
If sin θ = cos θ, then find the value of 2 tan θ + cos² θ.
Solution:
sin θ = cos θ (Given)
It means value of θ = 45°
Now, 2 tan θ + cos² θ = 2 tan 45° + cos² 45°

Introduction To Trigonometry Class 10 Extra Questions With Answers Question 4.
If sin (x – 20)° = cos (3x – 10)°, then find the value of x.
Solution:
sin (x – 20)° = cos (3x – 10)°
⇒ cos [90° – (x – 20)°] = cos (3x – 10)°
By comparing the coefficient
90° – x° + 20° = 3x° – 10° = 110° + 10° = 3x° + x°
120° = 4x°
⇒ \(\frac{120^{\circ}}{4}\) = 30°

Class 10 Trigonometry Extra Questions Question 5.
If sin² A = \(\frac{1}{2}\)tan² 45°, where A is an acute angle, then find the value of A.
Solution:
sin²A = \(\frac{1}{2}\)tan² 45°
⇒ sin²A = \(\frac{1}{2}\) (1)² [∵ tan 45° = 1]
= sin² A = \(\frac{1}{2}\)
⇒ sin A = \(\frac{1}{\sqrt{2}}\)
Hence, ∠A = 45°

Extra Questions Of Trigonometry Class 10 Question 6.
If x = a cos θ, y = b sin θ, then find the value of b²x² + a²y² – a²b².
Solution:
Given x = acos θ, y = b sin θ
b²x² + a²y² – a²b² = b²(acos θ)² + a²(b sin θ)² – a²b²
= a²b² cos²θ + a²b² sin² θ – a²b² = a²b² (sin² θ + cos² θ) – a²b²
= a²b² – a²b² = θ (∵ sin² θ + cos² θ = 1)

Trigonometry Class 10 Questions Question 7.
If tan A = cot B, prove that A + B = 90°.
Solution: We have
tan A = cot B
⇒ tan A = tan (90° – B)
A = 90° – B
[∵ Both A and B are acute angles]
⇒ A + B = 90°

Extra Questions On Trigonometry Class 10 Question 8.
If sec A = 2x and tan A = \(\frac{2}{x}\), find the value of 2\(\left(x^{2}-\frac{1}{x^{2}}\right)\) .
Solution:

Class 10 Maths Chapter 8 Extra Questions Question 9.
In a ∆ABC, if ∠C = 90°, prove that sin² A + sin² B = 1.
Solution:
Since ∠C = 90°
∴ ∠A + ∠B = 180° – ∠C = 90°
Now, sin² A + sin² B = sin² A + sin² (90° – A) = sin² A + cos² A = 1

Trigonometry Extra Questions Question 10.
If sec 4A = cosec (A – 20°) where 4 A is an acute angle, find the value of A.
Solution:
We have
sec 4 A = cosec (A – 20°)
⇒ cosec (90° – 4 A) = cosec (A – 20°)
∴ 90° – 4 A = A – 20°
⇒ 90° + 20° = A + 4 A
⇒ 110° = 5 A
∴ A = \(\frac{110}{5}\) = 22°

Introduction to Trigonometry Class 10 Extra Questions Short Answer Type 2

Introduction To Trigonometry Class 10 Extra Questions Question 1.
If sin A = \(\frac{3}{4}\), calculate cos A and tan A.
Solution:
Let us first draw a right ∆ABC in which ∠C = 90°.
Now, we know that

Important Questions For Class 10 Maths Trigonometry With Solutions Question 2.
Given 15 cot A = 8, find sin A and sec A.
Solution:
Let us first draw a right ∆ABC in which ∠B = 90°.
Now, we have, 15 cot A = 8

Trigonometry Class 10 Extra Questions With Solutions Question 3.
In Fig. 10.5, find tan P – cot R.
Solution:

Using Pythagoras Theorem, we have
PR² = PO² + QR²
⇒ (13)² = (12)² + QR²
⇒ 169 = 144 + QR²
⇒ QR² = 169 – 144 = 25
⇒ QR = 5 cm
Now, tan P = \(\frac{QR}{PQ}\) = \(\frac{5}{12}\) and cot R = \(\frac{QR}{PQ}\) = \(\frac{5}{12}\)
tan P – cot R = \(\frac{5}{12}\) – \(\frac{5}{12}\) = 0

Class 10 Maths Trigonometry Extra Questions Question 4.
If sin θ + cos θ = √3 , then prove that tan θ + cot θ = 1.
Solution:
sin θ + cos θ = √3
⇒ (sin θ + cos θ)² = 3
⇒ sin² θ + cos² θ + 2 sin θ cos θ = 3
⇒ 2 sin cos θ = 2 (∵ sin² θ + cos² θ = 1)
⇒ sin θ. cos θ = 1 = sin² θ + cos² θ

⇒ 1 = tan θ + cot θ = 1
Therefore tan θ + cot θ = 1

Extra Question Of Trigonometry Class 10 Question 5.
Prove that \(\frac { 1-sinθ }{ 1+sinθ } \) = (sec θ – tan θ)²
Solution:

Without using tables, evaluate the following (6 to 10).

Question 6.

Solution:

Trigonometry Important Questions Class 10 Question 7.

Solution:

Extra Questions On Introduction To Trigonometry Class 10 Question 8.

Solution:

Trigonometry Problems For Class 10 Question 9.
Evaluate: sin 25° cos 65° + cos 25° sin 65°.
Solution:
sin 25°. cos 65° + cos 25° . sin 65°
= sin (90° – 65°). cos 65° + cos (90° – 65°). sin 65°
= cos 65° . cos 65° + sin 65°. sin 65°
= cos² 65° + sin² 65° = 1.

Class 10 Introduction To Trigonometry Extra Questions Question 10.
Without using tables, evaluate the following:
3 cos 68°. cosec 22° – \(\frac{1}{2}\) tan 43°. tan 47°. tan 12°. tan 60°. tan 78°
Solution:
We have,
3 cos 68°. cosec 22° – \(\frac{1}{2}\) tan 43°. tan 47°. tan 12°. tan 60°. tan 78°.
= 3 cos (90° – 22°). cosec 22° – \(\frac{1}{2}\) . {tan 43° . tan (90° – 43°)}. {tan 12°. tan (90° – 12°). tan 60°}
= 3 sin 22°. cosec 22° – \(\frac{1}{2}\)(tan 43° . cot 43°). (tan 12°. cot 12°). tan 60°
= 3 × 1 – × 1 × 1 × √3 = 3 – \(\frac{\sqrt{3}}{2}\) = \(\frac{6-\sqrt{3}}{2}\).

Question 11.
If sin 30 = cos (θ – 6°) where 30 and (θ – 6°) are both acute angles, find the value of θ.
Solution:
According to question:
sin 3θ = cos (θ – 6°)
cos (90° – 30) = cos (θ – 6°) [∵ cos (90° – θ ) = sin θ]
90° – 3θ = θ – 6° [comparing the angles)
= 4θ = 90° + 6° = 96°
θ = \(\frac{96}{4}\) = 24°
Hence, θ = 24°

Question 12.
If sec θ = x + \(\frac{1}{4x}\), prove that sec θ + tan θ = 2x or \(\frac{1}{2x}\).
Solution:
Let sec θ + tan θ = λ …..(i)
We know that, sec² θ – tan² θ = 1
(sec θ + tan θ) (sec θ – tan θ) = 1
⇒ λ(sec θ – tan θ) = 1
sec θ – tan θ = \(\frac{1}{\lambda}\) …..(ii)
Adding equations (i) and (ii), we get

Question 13.
Find an acute angle θ, when

Solution:

On comparing we get
⇒ tan θ = √3
⇒ tan θ = tan 60°
= θ = 60°

Question 14.
The altitude AD of a MABC, in which ∠A is an obtuse angle has length 10 cm. If BD = 10 cm and CD = 10√3 cm, determine ∠A.
Solution:

∆ABD is a right triangle right angled at D, such that AD = 10 cm and BD = 10 cm.
Let ∠BAD = θ
∴ tan θ = \(\frac{B D}{A D}\)
⇒ tan θ = \(\frac{10}{10}\) = 1
⇒ tan θ = tan 45°
⇒ θ = ∠BAD = 45° … (i)
∆ACD is a right triangle right angled at D such that AD = 10 cm and DC = 10√3 cm.
Let ∠CAD = Φ
∴ tan Φ = \(\frac{CD}{AD}\)
⇒ tan Φ = \(\frac{10 \sqrt{3}}{10}\) = √3
⇒ tan Φ = tan 60°
⇒ Φ = ∠CAD = 60°
From (i) & (ii), we have
∠BAC = ∠BAD + ∠CAD = 45° + 60° = 105°

Question 15.
If cosec θ = \(\frac{13}{12}\), evaluate \(\frac{2 \sin \theta-3 \cos \theta}{4 \sin \theta-9 \cos \theta}\)
Solution:

Question 16.
Prove that

Solution:

Question 17.
Prove that

Solution:
We have,

Question 18.
Prove that:

Solution:

Question 19.
Prove that:

Solution:

Question 20.
Evaluate the following:

Solution:

Question 21.
If tan (A +B) = √3 and tan (A – B) = \(\frac{1}{\sqrt{3}}\); 0° < A + B ≤ 90°; A > B, find A and B.
Solution:
We have, tan (A + B) = √3
⇒ tan (A + B) = tan 60°
∴ A + B = 60° …(i)
Again, tan (A – B) = \(\frac{1}{\sqrt{3}}\)
∴ A – B = 30° … (ii)
Adding (i) and (ii), we have
2A = 90°
⇒ A = 45°
Putting the value of A in (i), we have
45° + B = 60°
∴ B = 60° – 45o = 15°
Hence, A = 45° and B = 15°

Question 22.
If A, B and C are interior angles of a ∆ABC, then show that sin \(\left(\frac{B+C}{2}\right)\) = cos\(\frac{A}{2}\).
Solution:
Since A, B and C are the interior angles of a ∆ABC,

Question 23.
Prove that: (cosec θ – cot θ)² = \(\frac {1-\cos\theta}{1+\cos\theta}\)
Solution:
LHS = (cosec θ – cot θ)²

Question 24.
Prove that:

Solution:

Question 25.
Prove that: (sin A + cosec A)² + (cos A + sec A)² = 7 + tan² A + cot²A.
Solution:
LHS = (sin A + cosec A)² + (cos A + sec A)²
= sin² A + coses² A + 2sin A . cosec A + cos² A + sec² A + 2 cos A . sec A
= (sin² A + coses² A + 2) + (cos² A + sec² A + 2) [sin A. cosec A = 1]
= (sin² A + cos² A) + (coses² A + sec² A) + 4 [cos A. sec A = 1]
= 1 + 1 + cot²A + 1 + tan² A + 4
= 7 + tan² A + cot² A = RHS [∵ 1 + cot²A = coses² A and 1 + tan² A = sec² A]

Question 26.
Prove that:

Solution:

To obtain cot θ in RHS, we have to convert the numerator of LHS in cosine function and denominator in sine function.
Therefore converting sin² θ = 1 – cos² θ, we get

Question 27.
Prove that:

Solution:

Question 28.
Prove that:

Solution:

Question 29.
Without using trigonometric tables, prove that:

Solution:

Question 30.
Evaluate:

Solution:

Introduction to Trigonometry Class 10 Extra Questions Long Answer Type

Question 1.
In ∆PQR, right-angled at Q, PR + QR = 25 cm and PQ = 5 cm. Determine the values of sin P, cos P and tan P.
Solution:

We have a right-angled ∆PQR in which ∠Q = 90°.
Let QR = x cm
Therefore, PR = (25 – x) cm
By Pythagoras Theorem, we have
PR² = PQ² + QR²
(25 – x)² = 5² + x²
= (25 – x)² – x² = 25
(25 – x – x) (25 – x + x) = 25
(25 – 2x) 25 = 25
25 – 2x = 1
25 – 1 = 2x
= 24 = 2x
∴ x = 12 cm
Hence, QR = 12 cm
PR = (25 – x) cm = 25 – 12 = 13 cm
PQ = 5 cm

Question 2.
In triangle ABC right-angled at B, if tan A = \(\frac{1}{\sqrt{3}}\) find the value of:
(i) sin A cos C + cos A sin C (ii) cos A cos C – sin A sin C.
Solution:

We have a right-angled ∆ABC in which ∠B = 90°.
and, tan A = \(\frac{1}{\sqrt{3}}\)
Now, tan A = \(\frac{1}{\sqrt{3}}\) = \(\frac{BC}{AB}\)
Let BC = k and AB = √3k
∴ By Pythagoras Theorem, we have
⇒ AC² = AB² + BC²
⇒ AC² = (√3k)² + (k)² = 3k² + k²
⇒ AC² = 4k²

Question 3.
If cot θ = \(\frac{7}{8}\), evaluate:
(i)

(ii) cot² θ
Solution:
Let us draw a right triangle ABC in which ∠B = 90° and ∠C = θ.

Question 4.
If 3 cot A = 4, check whether \(\frac{1-\tan ^{2} A}{1+\tan ^{2} A}\) = cos² A – sin² A or not.
Solution:

Let us consider a right triangle ABC in which ∠B = 90°

Let AB = 4k and BC = 3k
∴ By Pythagoras Theorem
AC² = AB² + BC²
AC = (4k)² + (3k)² = 16k² + 9k²
AC² = 25k²
∴ AC = 5k

Question 5.
Write all the other trigonometric ratios of ∠A in terms of sec A.
Solution:

Let us consider a right-angled ∆ABC in which ∠B = 90°.
For ∠A we have

Question 6.
Prove that

Solution:

Question 7.
Prove that:

Solution:

Question 8.
Prove that

Solution:

= 2 cosec² A tan² A = 2(1 + cot² A). tan² A
= 2 tan² A + 2 tan² A. cot² A (∵ tan A cot A = 1)
= 2 + 2 tan² A = 2(1 + tan² A) = 2 sec² A = RHS.

Question 9.
Prove that: (sin θ + sec θ)² + (cos θ + cosec θ)² = (1 + sec θ cosec θ)².
Solution:
LHS = (sin θ + sec θ)2 + (cos θ + cosec θ)²

= (1 + sec θ cosec θ)² = RHS.

Question 10.
Prove that:

Solution:
In order to show that,

Question 11.
Prove that: \(\frac { cosecθ\quad +\quad cotθ }{ cosecθ\quad -\quad cotθ } \) = (cosec θ + cot θ) = 1 + 2 cot² θ + 2 cosec θ cot θ.
Solution:

= cosec² θ + cot² θ + 2 cosec θ. cot θ
= (1 + cot² θ) + cot² θ + 2 cosec θ. cot θ
= 1 + 2 cot² θ + 2 cosec . cot θ = RHS.

Question 12.
Prove that: 2 sec θ – sec θ – 2 cosec θ + cosec θ = cot – tan θ.
Solution:
LHS = 2 sec θ – sec θ – 2 cosec² θ + cosec θ
= 2 (sec² θ) – (sec² θ)2 – 2 (cosec² θ) + (cosec θ)²
= 2 (1 + tan² θ) – (1 + tan⁴ θ)2 – 2(1 + cot² θ) + (1 + cot² θ)⁴
= 2 + 2 tan² θ – (1 + 2 tan² θ + tan² θ) – 2 – 2 cot² θ + (1 + 2 cot² θ + cot θ) =
= 2 + 2 tan² θ – 1 – 2 tan² θ – tan⁴ θ – 2 – 2 cot² θ + 1 + 2 cot⁴ θ + cot⁴ θ
= cot⁴ θ – tan⁴ θ = RHS

Question 13.
Prove that: (cosec A – sin A) (sec A – cos A) = \(\frac{1}{\tan A+\cot A}\).
Solution:
LHS = (cosec A – sin A) (sec A – cos A)

Introduction to Trigonometry Class 10 Extra Questions HOTS

Question 1.
Prove that:
\(\frac{\tan \theta}{1-\cot \theta}\) + \(\frac{\cot \theta}{1-\tan \theta}\) = 1 + sec θ cosec θ = 1 + tan θ + cot θ.
Solution:

For second part
Now from (i), we have

Question 2.
If tan A = n tan B and sin A = m sin B, prove that cos² A = \(\frac{m^{2}-1}{n^{2}-1}\)
Solution:
We have to find cos² A in terms of m and n. This means that the angle B is to be eliminated from
the given relations.
Now, tan A = n tan B
⇒ tan B = \(\frac{1}{n}\) tan A
⇒ cot B = \(\frac{n}{\tan A}\)
and
sin A = m sin B

Question 3.
Prove the following identity, where the angle involved is acute angle for which the expressions are defined.
\(\frac { cosA-sinA+1 }{ cos A + sin A-1 } \) = cosec A + cot A, using the identity cosec² A = 1 + cot² A.
Solution:

= cosec A + cot A = RHS.

Question 4.
If x sin³ + y cos³ θ = sin θ cos θ and x sin θ = y cos θ, prove x² + y² = 1.
Solution:
We have, x sin³ + y cos³ θ = sin θ cos θ
⇒(x sin θ) sin² θ + (y cos θ) cos² θ sin θ cos θ
⇒ x sin θ (sin² θ) + (x sin θ) cos² = sin θ cos [∵ x sin θ = y cos θ]
⇒ x sin θ (sin² θ + cos² θ) = sin θ cos θ
⇒ x sin θ = sin θ cos
⇒ x = cos θ
Now, we have x sin θ = y cos θ
⇒ cos o sin θ = y cos θ [∵ x = cos θ]
⇒ y = sin θ
Hence, x² + y² = cos² θ + sin² θ = 1.

Question 5.
If tan θ + sin θ = m and tan θ – sin θ = n, show that (m² – n²) = 4√mn.
Solution:
We have, given tan θ + sin θ = m, and tan θ – sin θ = n, then
LHS = (m² – n²),= (tan θ + sin θ)² – (tan θ – sin )²
= tan² θ + sin² θ + 2 tan θ sin θ – tan² θ – sin² θ + 2 tan θ sin θ

Question 6.
If cosec θ – sin θ = l and sec θ – cos θ = m, prove that l² m² (l² + m² + 3) = 1.
Solution:
LHS = l² m² (l² + m² + 3).
= (cosec θ – sin θ)² (sec θ – cos θ)² {(cosec θ – sin θ)² + (sec θ – cos θ)² + 3}

In this page, we are providing Management of Natural Resources Class 10 Extra Questions and Answers Science Chapter 16 pdf download. NCERT Extra Questions for Class 10 Science Chapter 16 Management of Natural Resources with Answers will help to score more marks in your CBSE Board Exams. https://ncertmcq.com/extra-questions-for-class-10-science/

Class 10 Science Chapter 16 Extra Questions and Answers Management of Natural Resources

Extra Questions for Class 10 Science Chapter 16 Management of Natural Resources with Answers Solutions

Extra Questions for Class 10 Science Chapter 16 Very Short Answer Type

Sustainable Management Of Natural Resources Class 10 Important Questions Question 1.
List any two causes for deforestation taking place.  (CBSE 2009)
Answer:

1. Meeting the needs of growing population and using land for housing.
2. Setting up industries.
3. Converting into agricultural land.

Chapter 16 Science Class 10 Extra Questions Question 2.
Name any two forest products each of which is the basis for some industry. (CBSE 2009)
Answer:

1. Timber wood: Used in making paper and furniture.
2. Latex of rubber plant: In making tyres.
3. Resins and gums: Used in paints and varnishes.

Management Of Natural Resources Class 10 Questions And Answers Pdf Question 3.
Mention any one negative effect of our affluent life style on the environment.  (CBSE 2013, 2014)
Answer:
Chlorofluorocarbons used in refrigerators causing ozone hole. Carbon dioxide released on burning fossil fuels causing global warming.

Management Of Natural Resources Class 10 Important Questions Question 4.
List any two measures that you suggest for better management of water resources.  (CBSE 2013, 2014)
Answer:

1. Rainwater harvesting.
2. Reusing the rinsed water from washed clothes for cleaning or mopping the house.

Management Of Natural Resources Class 10 Questions And Answers Question 5.
Give one example each from your daily life where the household waste can be effectively reused and recycled respectively.  (CBSE 2013, 2014)
Answer:
Reuse: Empty plastic or glass bottles of jams and pickles
Recycle: Paper and empty polypacks of milk.

Class 10 Science Chapter 16 Important Questions Question 6.
Name any two items which can be easily recycled but are generally thrown in the dustbins by us.  (CBSE 2013, 2014)
Answer:
Paper, polypacks of milk, cold drink cans, etc.

Management Of Natural Resources Important Questions Question 7.
Write the main objective of conservation of biodiversity.  (CBSE 2013)
Answer:
To maintain ecological balance as loss of biodiversity leads to ecological instability.

Sustainable Management Of Natural Resources Important Questions Question 8.
Water is a valuable resource. List two ways that you would suggest every family member to save this resource. (CBSE 2014)
Answer:

1. Prevent leakage from tap and ensure timely repairs.
2. Reuse the rinsed water from washed clothes for watering plants in garden.

Management Of Natural Resources Class 10 Extra Questions Pdf Question 9.
“We need to manage our resources”. List two reasons to justify this statement.  (CBSE 2014)
Answer:

1. For equitable distribution of resources so that all people get their benefits.
2. Many resources are limited and would exhaust due to overexploitation.

Extra Questions for Class 10 Science Chapter 16 Short Answer Type I

Class 10 Science Chapter 16 Extra Questions Question 1.
List any four measures for conserving forests.  (CBSE 2009)
Answer:

1. Reduce the indiscriminate felling of trees.
2. Create awareness among people for conservation of forests.
3. Involving local people in management and conservation of forests.
4. Reforestation by promoting silviculture.
5. Providing protection to wildlife and endangered plants.
6. Making strict laws for conservation of forests.

Questions On Sustainable Management Of Natural Resources Question 2.
List any four advantages of water harvesting.  (CBSE 2009)
Answer:

1. Helps to recharge ground water.
2. Underground water does not act as breeding ground of mosquitoes.
3. Underground water does not get contaminated by human and animal wastes.
4. Provides moisture to the soil and crops.

Important Question Of Natural Resources Class 10 Question 3.
We often observe domestic waste decomposing in the by lanes of residential colonies. Suggest ways to make people realise that the improper disposal of waste is harmful to the environment.  (CBSE 2013)
Answer:

• Create awareness through campaigns and road rallies on the issue.
• Impose penalty on those found throwing wastes on the road.

Sustainable Management Of Natural Resources Class 10 Extra Questions Question 4.
List two environment-friendly practices or habits which need to be followed by every member of a family / community. Explain how these practices will support the “save the environment” mission. (CBSE 2014)
Answer:

• Segregation of wastes into biodegradable and non-biodegradable and ensuring their reuse and recycling, if possible.
• Less use of fossil fuels and switching to environment friendly alternatives like use of solar energy and wind energy, etc.

Important Questions From Sustainable Management Of Natural Resources Question 5.
What is meant by “Sustainable Management”? Why is reuse considered better than recycling?  (CBSE 2015)
Answer:
The judicious and wise use of resources to cater to the current basic needs and preserving the resources for the needs of future generations is called as Sustainable Management.
Recycling requires more amount of energy and money while no energy is required for the reuse of materials. So, reuse is better than recycling.

Natural Resources Class 10 Important Questions Question 6.
List two advantages associated with water harvesting at the community level. (CBSE 2015)
Answer:
Water harvesting at community level is advantageous as:

• It recharges the ground water and helps in increasing the vegetation around the area.
• It mitigates the chances of droughts and floods. It also increases income of farmers by increasing agricultural production in rural areas.

Management Of Natural Resources Class 10 Question 7.
Everyone of us can do something to reduce our personal consumption of various natural resources. List four such activities based on 3R’s approach.  (CBSE 2013, 2015)
Answer:

• Reduce wastage of water by repairing leaking taps.
• Recycle the wastes like paper, empty polypacks of milk, etc.
• Reuse the aluminium cans of cold drink, glass bottles of pickles, etc.
• Reduce the use of fossil fuels by switching over to cleaner and renewable sources of energy like solar energy.

Management Of Natural Resources Questions And Answers Question 8.
List two main causes of the pollution of water of the river Ganga. State how pollution and
contamination of river water prove harmful for the health of the people of neighbouring areas. (CBSE 2015)
Answer:
The two main causes of pollution of water of river Ganga are:

1. Disposal of domestic and industrial effluents into it.
2. Human activities like washing clothes, bathing, etc.

The harm to the people of neighbouring areas are:

1. Leads to water-borne diseases like cholera, typhoid, etc.
2. Harms the aquatic plants and animals in the water body.

Management Of Natural Resources Question Answers Question 9.
List any two advantages associated with water stored in the ground.  (CBSE 2015)
Answer:
The water stored in ground

1. does not evaporate
2. does not act as breeding ground of mosquitoes.

Class 10th Science Chapter 16 Question Answer Question 10.
What steps have been taken by West Bangal Government to protect badly degraded sal forests?
Answer:
By the efforts of A.K . Banerjee in Arabari forest range of Midnapore district the badly degraded sal forests were revived with the involvement and participation of local villagers. The villagers were in return given employment and were allowed to collect firewood and fuelwood at a nominal fee.

Management Of Natural Resources Class 10 Solutions Question 11.
Why are forests considered ‘biodiversity hot spots’? What would happen due to loss of biodiversity?
Answer:
Wide variety of plants, animals, microorganisms are found in forests. So they act as biodiversity hotspots. Loss of biodiversity disturbs ecological balance.

Sustainable Management Of Natural Resources Class 10 Solutions Question 12.
Prepare a list of five items that you use daily in the school. Identify from the list such items that can be recycled. (NCERT Exemplar)
Answer:
Paper, Plastic pencil box or Tiffin box, Steel spoon, Scale, Eraser.

Management And Natural Resources Class 10 Question 13.
List two advantages associated with water harvesting at the community level.  (NCERT Exemplar)
Answer:

1. Recharging of wells leads to increase in ground water level.
2. Ground water does not evaporates and keeps the layers of soil above it moist.
3. The water stored during rainy season can be used when required.

Sustainable Management Of Natural Resources Question Answer Question 14.
What measures would you take to conserve electricity in your house?  (NCERT Exemplar)
Answer:

• Switch off the fans and lights when they are not required.
• Use solar water heaters during winters.
• Use LED lights instead of normal bulbs or tube lights.

Question 15.
Although coal and petroleum are produced by degradation of biomass, yet we need to conserve them. Why? (NCERT Exemplar)
Answer:
It takes millions of years to form coal and petroleum and their reserves are limited. Due to this they would get exhausted very soon if utilised at a faster rate. Hence, they should be conserved for the needs of the future generations too.

Question 16.
Suggest a few measures for controlling carbon dioxide levels in the atmosphere.  (NCERT Exemplar)
Answer:

• Plant more and more trees.
• Using cleaner fuels like CNG.
• Make manure from litter instead of burning it.
• The harmful effluents from industries should be treated before discharging them into the atmosphere.
• Less use of fossil fuels.

Extra Questions for Class 10 Science Chapter 16 Short Answer Type II

Question 1.
What are natural resources? State two factors that work against an equitable distribution of these resources. (CBSE 2009)
Answer:
The stock of nature such as air, water, soil, minerals, forests and wildlife are called as natural resources. The two factors that work against their equitable distribution are

1. Overuse of resources and their overexploitation.
2. Human activities like cutting of trees, hunting, etc. which disturbs ecological balance.

Question 2.
What is water harvesting? Mention any two water harvesting structures.  (CBSE 2009)
Answer:
Capturing rainwater where it falls or capturing the run-off water so that it can be made available throughout the year for various purposes is called water harvesting.
Some traditional water harvesting structures are:

1. Khadins, tanks and nadis in Rajasthan
2. Kulhs in Himachal Pradesh.

Question 3.
How can we as an individual help in reducing the use of fossil fuels? Mention two ways.
Answer:
We can reduce the use of fossil fuels by .

1. Switching over to renewable sources of energy like solar energy, wind energy, etc.
2. Use public transport instead of private vehicles,
3. Ensure proper servicing and tuning of vehicles to increase fuel efficiency.

Question 4.
What is meant by exploitation of resources with short aims? List its four advantages.  (CBSE 2009)
Answer:
Use of resources for the benefit of a few rich and powerful people in order to fulfil short-term aims and the present needs is called exploitatation of resources with short aims. Its advantages are:

1. Maximises profit without any accountability.
2. Increases growth rate of economy for that duration.
3. They fulfil the needs of the present generation.
4. Ensures availability of a variety of raw materials for human use.

Question 5.
(a) List any two disadvantages of using fossil fuels for the production of energy.
(b) Give two examples each of the following:
(i) Renewable sources of energy. 3
(ii) Non-renewable sources of energy.  (CBSE 2011)
Answer:
(a) Disadvantages of using fossil fuels:

• The oxides of nitrogen and sulphur released on burning fossil fuels reacts with water vapour in air and falls in the form of harmful acid rain.
• Carbon dioxide released on burning them causes greenhouse effect which leads to global warming.
• Carbon monoxide releases on their combustion is toxic and can be fatal.
• They are limited, non-renewable resources which may get exhausted soon.

(b) (i) Examples of renewable sources of energy are

• Solar energy
• Wind energy

(ii) Examples of non-renewable sources of energy are

• Petrol
• Diesel

Question 6.
Dams are useful for the society but there is public opposition to the construction of large dams. Justify your answer by giving three problems.  (CBSE 2011)
Answer:

• Social problems: Large number of human settlements gets submerged in water during construction of dam.
• Environmental problems: Loss of vast variety of flora-fauna due to deforestation and biodiversity loss during construction of dams.
• Economic problems: Huge amount of public money is spent without getting proportionate benefits from such dams.

Question 7.
List the products of combustion of fossil fuels. What are their adverse effects on the environment?  (CBSE 2012)
Answer:
Carbon dioxide, sulphur dioxide, nitrogen oxide, water, carbon monoxide are the products of combustion of fossil fuels.
Their adverse effects on the environment are:

• Carbon dioxide is a greenhouse gas which leads to global warming.
• Oxides of nitrogen and sulphur react with water vapour present in air to form acids which fall in the form of acid rains and harms life.
• Carbon monoxide is a toxic gas which creates respiratory problems.

Question 8.
What is environmental planning? List any four human activities that are directly connected to influence the environment of a region.
Answer:
Various steps taken to reduce pollution and conserve natural resources for long term use is called environmental planning. It is necessary to maintain ecological balance. Human activities that are directly connected to influence the environment of a region are:

• Large scale deforestation for agricultural land or housing needs of growing population.
• Discharge of domestic wastes and industrial effluents into water bodies.
• Excessive use of fossil fuels which causes air pollution.
• Excessive use of non-biodegradable materials, plastics, detergents, etc. which harm the environment.

Question 9.
What is the full form of GAP? Why was it started? What is the main cause of abundant coliform in the river Ganga?
Answer:
GAP-Ganga Action Plan:
GAP was started to ensure the cleaning of water of river Ganga and reduce the pollution levels of Ganga. Main cause of abundant coliform bacteria in river Ganga is due to high amount of organic wastes disposed in the form of unburnt corpses into the water.

Question 10.
In a village in Karnataka, people started cultivating crops all around a lake which was always filled with water. They added fertilisers to their field in order to enhance the yield. Soon they discovered that the waterbody was completely covered with green floating plants and fishes started dying in large numbers.
Analyse the situation and give reasons for excessive growth of plants and death of fish in the lake. (NCERT Exemplar)
Answer:
The fertilisers containing high amount of phosphates and nitrates got carried down by rainwater into the lake which led to nutrient enrichment of water in lakes. This caused excessive growth of aquatic plants which ultimately covered the whole surface of the water body. Due to this insufficient amount of light entered the water body and levels of oxygen became low. This led to death of fishes in the water body.

Question 11.
(a) Locate and name the water reservoirs in Figures (a) and (b).
(b) Which has an advantage over the other and why?


Answer:
(a) The water reservoir in Figure (a) is a pond.
The water reservoir in Figure (b) is an underground water body.

(b) Figure (b) has more advantage than Figure (a), because the advantages of water stored in the ground are many. For example

• It does not evaporate.
• Spreads out to recharge wells and provides moisture for vegetation over a wide area.
• Does not provide breeding grounds for mosquitoes like stagnant water.

Extra Questions for Class 10 Science Chapter 16 Long Answer Type

Question 1.
What is a dam? Write two main advantages and two ill-effects of constructing big dam.  (CBSE 2009)
Answer:
Dams are constructed across the rivers to regulate the flow of water and store the huge amounts of water in large reservoirs. This ensures the supply of water for irrigation and other purposes.

Advantages of Dams:

• Ensures water availability for irrigation of fields.
• Water can be used to generate electricity in Hydel power stations by using turbines.

Disadvantages of dams:

• Social problems: Human settlements get submerged under water.
• Environmental problems: Large scale loss of biodiversity and deforestation.
• Economic problems: Huge amount of public money utilised in their construction but benefits are not proportionate.

Question 2.
Define Reduce, Recycle and Reuse with reference to the environment. Which is better strategy among recycle and reuse? Why?
Answer:
Recycle: Recycling wastes like paper, plastic and glass to obtain materials for use.
Reduce: Minimise the use of natural resources.
Reuse: Encourage the use of things again and again instead of throwing them away.
Reuse is better than recycling.

Recycling requires large amount of energy and money whereas reuse does not require any energy. So, reuse is better than recycling.

Question 3.
Prepare a list of five activities that you perform daily in which natural resources can be conserved or energy utilisation can be minimised.  (NCERT Exemplar)
Answer:

• Taking a bus, public transport or walking/cycling instead of a private vehicle.
• Using LED bulbs in homes instead of normal bulbs.
• Talking the stairs instead of lift.
• Using fan and light only when required.
• Using solar water heating devices.

Question 4.
Is water conservation necessary? Give reasons.  (NCERT Exemplar)
Answer:
The total amount of fresh water is more than enough to meet the needs of human beings. But due to its uneven distribution, wide seasonal, as well as yearly fluctuation in rainfalls and wastage, water shortage is a chronic problem inmost parts of the world.

Management of Natural Resources HOTS Questions With Answers

Question 1.
What is meant by ‘Sustainable Management’? The environmentalists are insisting upon sustainable natural resources management. State its four advantages.  (CBSE 2009)
Answer:
The judicious and wise use of resources to cater to the current basic needs and preserving the resources for the needs of the future generations is called sustainable management. Its advantages are:

1. Prevents exploitation of resources for short term gains and targets the long term aims.
2. Ensures equitable distribution of resources.
3. Minimises the harm caused to the environment.
4. Ensures the availability of resources for their use by the future generations in order to fulfil their needs.

Question 2.
With the help of an example show that ‘reuse’ strategy is better than recycling.  (CBSE 2010)
Answer:
Recycling involves use of energy and money whereas no energy is used in ‘reuse’, so reuse is better than recycling.

For example,
The plastic bottles can be recycled by heating them and remoulding them into different shapes. But, this would require the use of energy resources for getting heat required for remoulding plastic. Also, cost of the energy resource will have to be met. Instead of this, the plastic bottles can be reused for different purposes which will save both money and energy.

Question 3.
Prejudice against traditional use of forests areas has no basis. Explain with an example.
Answer:
Local people were not allowed by the Government to use the forests in the traditional ways they had been using for generations. This has led to harmful effects on the sustainability of forests and its resources. A striking example of such case is: Nomadic shepherds used to take their sheep for grazing in the alpine meadows of Great Himalayan Peak during summers. But when they were not allowed to take sheep for grazing, it was seen that grass in the region grew very tall and then fell over preventing fresh growth, which proved harmful for the biodiversity of the region.

Question 4.
Suggest a few useful ways of utilising waste water.  (NCERT Exemplar)
Answer:
Ways of utilising waste water are:

• Ground water level can be recharged.
• Can be used for construction purposes.
• Washing cars and watering gardens by treated waste water.
• Organic wastes in waste water may be used as fertilisers for crops.

Question 5.
What is the importance of forest as a resource?  (NCERT Exemplar)
Answer:
Forest are important as a resources because they

• Provide shelter and food to wildlife.
• Maintain balance of oxygen and carbon dioxide in the atmosphere.
• Increase water holding capacity of soil and prevent soil erosion.
• Help to regulate the water cycle.
• Products like fuel, wood, timber, paper, etc. are obtained.
• Products like fruits, resins, gums, essential oils, etc. used in various industries are obtained.

Question 6.
Why are the Arabari forests of Bengal known to be a good example of conserved forest?  (NCERT Exemplar)
Answer:
Due to efforts of forest officer A.K. Banerjee, the Sal forests in Arabari forests of West Bengal were revived with the active participation of the local people in their conservation. In return the villagers were given employment in both silviculture and harvesting operations, 25 per cent of the final harvest, and allowed fuel wood and fodder collection on payment of a nominal fee.

By 1983, due to the active and willing participation of the villagers, the previously worthless Sal forests in Arabari forest range of Midnapore district Underwent a remarkable recovery and were valued ₹ 12.5 crores.

Extra Questions for Class 10 Science Chapter 16 Value Based Questions

Question 1.
An environmentalist on visit to your school suggested the use of three R’s to save the environment. Explain what he meet by three R’s and how would you follow his advice at home. What values will be evident in this? (CBSE 2009)
Answer:
The three R’s are Reduce, Recycle and Reuse.
Reduce: It means to minimise the use of natural resources.
Recycle: It means to recycle the wastes to obtain materials again for use.
Reuse: It means to use the things again and again instead of throwing them way.

We would follow his advice at home by reducing use of fossil fuels, recycle the non-biodegradable materials and reuse the plastic and glass bottles of jams and pickles.
The values evident are: Awareness, Eco-friendly care for Nature and environment, Scientific aptitude.

Question 2.
Subhash has started the project of constructing his building. His architect suggested that he should add a system of rainwater harvesting in his building. He thought by adopting water harvesting in his project, he can solve his water crisis problem in the years to come.
(i) Is Subhash correct in his approach? Support your answer.
(ii) Give the values shown by Subhash.  (CBSE 2012)
Answer:
(i) Yes, Subhash is correct in adopting water harvesting in his project because the rainwater falling on the roof can be collected and used for recharging the ground water instead of flowing into drains. This would increase the ground water as it neither evaporates nor acts a breeding ground for mosquitoes like the water stored on surface. It also does not get contaminated by the human or animal wastes.

(ii) The values shown by Subhash:

• Scientific aptitude, Decision-Making
• Environment Friendly, Care for Nature.

Check the below NCERT MCQ Questions for Class 10 Geography Chapter 5 Extra Questions and Answers Minerals and Energy Resources with Answers Pdf free download. https://ncertmcq.com/extra-questions-for-class-10-social-science/

Minerals and Energy Resources Class 10 Extra Questions Geography Chapter 5

Class 10 Geography Chapter 5 Extra Questions Question 1.
When did the Energy Conservation Act in India come into effect?
Answer:
In March 2002.

Minerals And Energy Resources Class 10 Extra Questions And Answers Question 2.
How much wind power potential does India have?
Answer:
About 20,000 MW.

Minerals And Energy Resources Class 10 Important Questions Question 3.
Where is the largest solar plant of India located?
Answer:
In Madhapur near Bhuj.

Minerals And Energy Resources Class 10 Extra Questions Question 4.
What is the non-conventional energy potential of India?
Answer:
Trie non-conventional energy potential of India is estimated at about 95,000 MW.

Extra Questions For Class 10 Geography Chapter 5 Question 5.
How much electricity is generated from nuclear plants?
Answer:
The gross electricity generated from nuclear plants is 2720 MW per day.

Geography Chapter 5 Class 10 Questions And Answers Question 6.
How many thermal power plants does India have?
Answer:
India has more than 310 thermal power plants.

Class 10 Geography Chapter 5 Question Answer Question 7.
What is the share of thermal electricity in India?
Answer:
The share of thermal electricity in India is about 70%.

Class 10 Geography Chapter 5 Important Questions Question 8.
What is the share of hydroelectricity in our country?
Answer:
Hydroelectricity accounts for 25% of the total electricity.

Minerals And Energy Resources Extra Questions Question 9.
What is the total hydel power potential of India?
Answer:
Total hydel power potential for India is estimated at 150,000 MW.

Class 10 Geography Chapter 5 Extra Questions And Answers Question 10.
How much of the total hydel power potential has already been developed?
Answer:
Only one-sixth.

Class 10 Geography Chapter 5 Questions And Answers Question 11.
Differentiate between thermal power and hydel power.
Answer:
Thermal Power
1. It is generated by using coal, petroleum and natural gas.
2. This type is power is not eco-friendly
3. Thermal power cannot be the permanent source of electricity as the sources of generating this type of power are limited and are showing signs of exhaustion.

Hydel Power
1. It is generated from turbines which run by the use of running water.
2. This type of power is comparatively eco-friendly.
3. This can be the source of electricity supply because water is a non-exhaustible resource because 2/3 of our earth is covered by water.

Minerals And Power Resources Extra Questions Question 12.
Point out the importance of natural gas.
Answer:

• Natural gas has been proved a very convenient source of energy.
• The use of natural gas in cooking has saved a huge quantity of coal and wood and has saved out world from pollution to a large extent.
• Natural gas-based power plants save much time and expenditure.
• Natural gas-based power plants save much time and expenditure.
• Natural gas can be used as an industrial raw material in petrochemical industry.

Minerals And Energy Resources Class 10 Questions And Answers Question 13.
Point out the reason why the annual production of gold has been dwindling in India?
Answer:
The annual production of gold has been dwindling in India because of the following reasons-

• The reserve of gold are in fact very small.
• Gold mines are very deep in India. Hence it is quite difficult to extract gold from them.
• The mining of gold has been in progress in India for a long time.
• Hence much of the gold ore has already been exhausted and there is very little ore to be mined.

Minerals And Energy Resources Class 10 Map Work Question 14.
Point out the importance of Neyveli Lignite fields.
Answer:

1. Neyveli Lignite fields are in Tamil Nadu. These have been just like a boon for the state.
2. Thermal power produced from the lignite coal of Neyveli fields has proved very useful for the industrialization of Tamil Nadu.

Extra Questions Of Mineral And Power Resources Question 15.
Explain the reasons why solar energy in Rajasthan and Biogas in the Northern plains have greater potential as non-conventional energy?
Answer:
The solar energy in Rajasthan and Biogas in the Northern plains gets more importance because of the geographical characteristics of these places. For example-

• In Rajasthan, it gets unperturbed sunshine for the most part of the year.
• In Northern India, animal waste is abundantly available hence biogas is more easily prepared here.
• These parts of India are climate-wise very appropriate for the biogas production.

Question 16.
“As compared to coal and mineral oil, hydroelectricity is a key source of energy.” Explain.
Or
Which is the best source of energy among coal, mineral oil and hydroelectricity? Give your point of view.
Answer:
Coal and mineral oil have been considered as the main source of power supply for a long time. The industrial developed countries have always used them as the main source of power supply. On the other hand, countries with limited reserves of these resources were forced to import these.

Because of all these facts, the world reserves of these minerals have begun to show the signs of exhaustion. In the teeth of fear of their exhaustion, some new sources of power supply had been invented and developed.

Hydel power is one such source. Hydel power has become more important nowadays in comparison to both coal and mineral oil. Because of this fact, every effort is being made to convert it into a permanent source of power supply. For this purpose, many large dams are being raised to maintain a constant supply of water to produce electricity.

That is why the hydel power has been developed mostly in both the developing and developed countries especially by those countries which posses limited or no coal reserves. Hydel power in comparison to coal and mineral oil is cheaper as well as pollution-free. It also provides advantages to hydel power in comparison to coal and mineral oil.

Question 17.
Give an account of the various uses of petroleum and the potential petroleum reserves in India.
Or
Write short notes on the following points-
1. Potential of the areas of the mineral oil deposits,
2. Production trend of mineral oil in India.
3. Increased demand and growth of mineral oil in India.
Answer:
Petroleum is the only multipurpose fuel of today’s world. It is also the most important source as thermal energy and motive power. In the recent years, the consumption, production, import and export of the mineral oil has assumed a wide scope especially for the developing countries like India. The uses of petroleum and petroleum resources is getting more and more importance every day.

Potential of the areas of the mineral oil deposits: The potential oil-bearing areas of deposits in India are tentatively estimated to be over one million square km. It covers Assam, the northern plains, the coastal strips, Gujarat, desert area, Thar, southern areas, Andaman and Nicobar islands and offshore sea.

The most important oil fields which are already serving the nation are located at Digboi, Naharkatiya, Moran, Ankleshwar, Cambay, Bombay-High, Kalol etc. Gas reserves are generally found in association with oil fields. However, there are certain other areas which are exclusively known for gas reserves. These areas are located in Tripura, Rajasthan, Offshore oil fields of Gujarat, Maharashtra, Tamil Nadu, Andhra Pradesh and Orissa.

Production trend of mineral oil in India : Before independence, Assam was the only state drilling and refining mineral oil. After independence, various new fields were found elsewhere in India like Gujarat, Bombay-High etc. India continued developing its technology and investing new areas. As a result, the production in the field of oil and natural gas has shown a continuous upward trend.

Increased demand and growth: Though India is producing more and more oil yet production of mineral oil in India is much less than the need of the country. In fact because of the development in every field and sector, the demand for mineral oil is increasing day by day. To fulfill its demand India is importing it. It is putting a great burden on our foreign exchange reserves. Hence India must find out alternative options.

Refining industries in India: Before its independence, India had only one oil refinery at Digboi in Assam. However today India has 8 refineries. All of these are helping India to fulfil its needs to a great extent, The refining capacity of these refineries is about 112.52 million tonnes a year. However, about 50 million tonnes of petroleum and petroleum products are being imported today.

Multiple Choice Questions

Question 1.
The following region produces more than 50% of the country’s copper:
(a) Balaghat
(b) Khetri
(c) Katni
(d) Nellore.
Answer:
(a) Balaghat

Question 2.
One of the following is not the major mica producing area:
(a) Ajmer
(b) Nellore
(c) Koderma
(d) Balaghat.
Answer:
(d) Balaghat.

Question 3.
The following is the low-grade coal:
(a) Bituminous
(b) Anthracite
(c) Lignite
(d) None of these.
Answer:
(c) Lignite

Question 4.
Naharkatiya is in the following state:
(a) Madhya Pradesh
(b) Assam
(c) Maharashtra
(d) Tamil Nadu.
Answer:
(b) Assam

Question 5.
Uranium and thorium are available in:
(a) Punjab
(b) Haryana
(c) Jharkhand
(d) West-Bengal
Answer:
(b) Haryana

Map Skills

Question 1.
Show the main minerals produced in India on the outline map of India.
Answer:

Question 2.
On the outline map of India. show the following:
(a) Iron ore belt
(b) Iron ore mines,
(c) Exporting ports.
Answer:

Question 3.
On the outline map of India, show the following:
(a) Mica belts,
(b) Manganese ore area
(c) Bauxite area,
(d) Mica area.
Answer:

Question 4.
On the outline map of India, show the following:
(a) Nuclear Plants
(b) Thermal Plants

Question 5.
On the outline map of India, show the following:
(a) Coal mines
(b) Oil Fields
(c) Major Natural Gas Reserves
(d) Natural Gas Pipelines
Answer:

Extra Questions for Class 10 Social Science

Check the below NCERT MCQ Questions for Class 10 Geography Chapter 7 Extra Questions and Answers Lifelines of National Economy with Answers Pdf free download. https://ncertmcq.com/extra-questions-for-class-10-social-science/

Lifelines of National Economy Class 10 Extra Questions Geography Chapter 7

Lifelines Of National Economy Class 10 Extra Questions And Answers Question 1.
How many foreign tourists visit India per year?
Answer:
About 2.6 million.

Class 10 Geography Chapter 7 Extra Questions Question 2.
How much rupees were earned by India in the year 2004?
Answer:
About 21828 crore.

Lifelines Of National Economy Extra Questions Question 3.
What was the part constituted by import in India’s foreign trade in 2000-01?
Answer:
About 53%.

Extra Questions For Class 10 Geography Chapter 7 Question 4.
What is the length of India’s coastline?
Answer:
75166 km.

Lifelines Of National Economy Class 10 Important Questions And Answers Question 5.
How many ports are there in India?
Answer:
India has 12 major and 181 medium and minor seaports.

Chapter 7 Sst Class 10 Geography Question 6.
How many radio stations are there in India?
Answer:
200.

Chapter 7 Geography Class 10 Important Questions Question 7.
How many telephone exchanges are there in India?
Answer:
About 37565.

Extra Questions Of Chapter Lifelines Of National Economy Question 8.
What is the length of Champakara canal?
Answer:
14 km.

Class 10 Geography Lifelines Of National Economy Important Questions Question 9.
Which of the national waterways is the smallest one?
Answer:
The Champakara canal.

Extra Questions Of Lifelines Of National Economy Question 10.
When was the air transport nationalised?
Answer:
In 1953.

Lifelines Of National Economy Important Questions Question 11.
Point out the significance of the unsurfaced roads in India.
Answer:
The significance of the unsurfaced roads in India are the following-

• The unsurfaced roads are easy to construct and easy to maintain.
• They can even be made to pass easily through forests and deserts and mountains.
• These are of great importance, especially in rural areas.
• They connect different villages easily.
• These roads also connect villages with national highways.

Class 10 Sst Extra Questions Question 12.
What is the importance of road transport as a means of transport?
Answer:
The importance of road transport as a means of transport are the following-

• This means of transport is comparatively more flexible.
• With the help of it, the goods can be carried out from the very doors of the seller to those of the buyers.
• In the hilly area road transport assures a great importance of its own.
• Roads are comparatively easy to construct and also easy to maintain.
• This transport provides link to railways also.
• The roads can also be conducted to connect even the remotest of villages with the national highways or other important places.

Social Science Class 10 Extra Questions Question 13.
Write down the importance of air transport.
Or
Air transport is getting more and more important these days. Give points.
Or ‘
Why is the air transport getting more and more importance these days?
Answer:
The importance of air transport in present context is getting more and more important because of the following reasons:

• Air travel is the faster means of transport.
• It saves a lot of time and energy.
• It facilitates business transactions and bring administrative efficiency.
• It makes accessibility possible in the remotest areas also.
• Air transport fulfils the needs of every type ranging from military to the civilian.

Important Questions Of Lifelines Of National Economy Class 10 Question 14.
Point out the major changes in the development of the Indian railway since independence.
Or
Why are the means of transport and communication the lifelines of a nation and its economy?
Or
What do you understand by the lifeline of our country?
Or
Write down in you own words the importance of transport and communication.
Answer:
In today’s modern world the means of transport and communication have no doubt turned as the lifelines of a country and also of its economy. The various forms of transport that are used to carry passengers and goods from one place to another are called the means of transport. On the other hand, communication means sending messages from one place to another.

These are known as the ‘Lifelines’ of a country because of the following reasons-

• They bring the far-flung areas of a country quite closer to each other.
• They carry the greatest number of passengers in longest journeys in lesser time but with greater comforts.
• They carry thousands of tonnes of different commodities from one part of the country to the other and thus avoid much hardships to the people.
• Also in the war times, their importance can hardly be emphasized. They bring the whole country at the back of the armed forces and facilitate the movement of arms, ammunition and other supplies.
• These means of communication and transport also help the Government to maintain law and order.
• These various means have also forged the bonds of national unity in our country by promoting social and cultural contacts between the various people of the country.

Ncert Extra Questions Class 10 Social Science Question 15.
Giving the various examples from the different parts of India, compare and contrast roads and railways as a means of transport.
Or
Transport is the prerequisite for modem industry. Explain.
Or
Does the road transport score over the railway’s transport?
Answer:
In the today’s modern industrial age, roads and railways, as means of transport, have great importance. They are in fact just like the lifelines of modern industries and in modern economy. In fact, both of these means of transport are interdependent on each other and can help each other in numberous ways. For example, the trucks can take the raw materials from the railway stations. The railway can carry these heavy goods to long distances and then trucks can take these materials to the different markets.

Though both the railways and roads are necessary for the development of the modern industries yet the road transport has acquired great importance of its own. It has in fact the following facts in its support- Roads are of considerable significance for passengers and goods traffic in India. Roads are relatively easy to construct and also to maintain.

The investment in roadways is also much less than that of in the railways. The most significant fact about the roads and the road traffic is that they can negotiate high radiant and can be brought almost to our doorsteps, unlike the railways. The road transport is faster than railway transport. Loading, unloading and transhipment from one gauge to another is easily facilitated by the road transports.

Road transport is easier and trans-shipment from one gauge to another is easily facilitated by the road transports.
Road transport is easier and also easier for private use. Trucks or buses can be hired at any time and for any place.
Inspite of all the above factors, as the means of transport both the railways and the roadways are needed for the full development of the industries in our country because they have their own specific uses. As a matter of fact in our country long-distance routes in India are connected by railways whereas shorter distances are connected by road. Hence facilitating each other. So we must pay attention to the development of both of the transport means.

Multiple Choice Questions

Question 1.
International trade is carried between:
(a) Two and more cities
(b) Two and more towns
(c) Two and more provinces
(d) Two and more countries.
Answer:
(d) Two and more countries.

Question 2.
The air transport was nationalised in:
(a) 1953
(b) 1954
(c) 1955
(d) 1956
Answer:
(a) 1953

Question 3.
Haldia port was developed to help relieve the growing pressure of the following:
(a) Mumbai port
(b) Chennai port
(c) Kolkata port
(d) None of these
Answer:
(c) Kolkata port

Question 4.
The Ganga waterways between Allahabad and Haldia is:
(a) 891 km
(b) 1620 km
(c) 168 km
(d) None of these
Answer:
(b) 1620 km

 

Map Skills

Question 1.
On the outline map of India, show the following:
(i) National Highways
(ii) Railways ‘
(iii) Major sea routes, ports, International Airports.
(iv) None of these
(v) Map No. 1.
Answer:

Extra Questions for Class 10 Social Science

We are solving NCERT class 10 textbook Solutions for Maths, Science, Social Science and Hindi. These solutions are developed according to the CBSE marking scheme.

NCERT Solutions for Class 10

Here we have Provided Updated NCERT Solutions for Class 10 for 2019 CBSE Board Exams. Class 10 NCERT Solutions clear your concepts to the core ensuring to stay with you in the long run. These are created by experts in accordance with the CBSE curriculum. You can find 100% accurate step-by-step solutions for every question in all the latest NCERT 10th Class books. Practice with these daily to perform better in board Exams.

Why NCERT Solutions for Class 10 Solutions are important?

The Central Board of Secondary Education has reintroduced the board exams for class 10 from 2017-18 and onwards. CBSE has prescribed NCERT books for all students who are studying CBSE schools. Most of the board exams questions are based on NCERT books.

Class 10 English First Flight Summary

• A Letter to God Summary
• Nelson Mandela Long Walk to Freedom Summary
• His First Flight Summary
• The Black Aeroplane Summary
• Two Stories about Flying Summary
• From the Diary of Anne Frank Summary
• The Hundred Dresses Part 1 Summary
• The Hundred Dresses Part 2 Summary
• A Baker From Goa Summary
• Coorg Summary
• Tea From Assam Summary
• Glimpses of India Summary
• Mijbil the Otter Summary
• Madam Rides the Bus Summary
• The Sermon at Benares Summary
• The Proposal Summary
• Dust of Snow Summary
• Fire and Ice Summary
• A Tiger in the Zoo Summary
• How to Tell Wild Animals Summary
• The Ball Poem Summary
• Amanda Summary
• Animals Summary
• The Trees Summary
• Fog Summary
• The Tale of Custard the Dragon Summary

Class 10 English Footprints Without Feet Summary

• A Triumph of Surgery Summary
• The Thief’s Story Summary
• The Midnight Visitor Summary
• A Question of Trust Summary
• Footprints without Feet Summary
• The Making of a Scientist Summary
• The Necklace Summary
• The Hack Driver Summary
• Bholi Summary
• The Book That Saved the Earth Summary

Class 10 English Literature Reader Summary

• Two Gentlemen of Verona Summary
• Mrs. Packletide’s Tiger Summary
• The Letter Summary
• A Shady Plot Summary
• Patol Babu Summary
• Virtually True Summary
• The Frog and the Nightingale Summary
• Mirror Summary
• Not Marble, Nor the Gilded Monuments Summary
• Ozymandias Summary
• The Rime of the Ancient Mariner Summary
• Snake Summary
• The Dear Departed Summary
• Julius Caesar Summary
• From the Diary of Anne Frank Summary (The Diary of a Young Girl Summary)
• The Story of My Life Summary

Check the below NCERT MCQ Questions for Class 10 Civics Chapter 4 Extra Questions and Answers Gender Religion and Caste with Answers Pdf free download. https://ncertmcq.com/extra-questions-for-class-10-social-science/

Gender Religion and Caste Class 10 Extra Questions Civics Chapter 4

Class 10 Civics Chapter 4 Extra Questions Question 1.
Define gender division.
Answer:
Gender division refers to the unequal roles assigned by the society to men and women.

Gender, Religion And Caste Class 10 Notes Questions And Answers Question 2.
What is the result of the sexual division of labour?
Answer:
The result of sexual division of labour is that women have been confined to the private domain of family, while the public domain has been monopolised by the men.

Important Questions Of Chapter Gender, Religion And Caste Class 10 Question 3.
Why does girl child gets dropped out from the school as compared to male child?
Answer:
Because parents prefer to spend their resources for their boy’s education rather than spending equally on their sons and daughters.

Gender, Religion And Caste Class 10 Questions And Answers Pdf Question 4.
What is the sex ratio in India?
Answer:
Sex ratio means number of girl child per one thousand boys. According to census of India 2001, the sex ratio in India was 927:1000.

Class 10 Civics Chapter 4 Important Questions Question 5.
What were Gandhiji’s views on religion?
Answer:

• Gandhiji did not consider religion as Hinduism, Islam or Christianity. To him, every religion was based on some belief system supported by rituals. He tried to get rid of rituals as far as possible.
• To him religion was a human institution that helped people solve practical affairs. He believed that the moral values drawn from all the religions should be used to guide the political system.

Gender Religion And Caste Extra Questions Question 6.
Write down Human Rights Groups views about religious minorities.
Answer:

• Human rights groups in India have argued that most of the victims of communal roits in our country are people from religious minorities.
• They have demanded that the government should take special steps to protect religious minorities.

Gender Religion And Caste Class 10 Extra Questions And Answers Question 7.
Why was India declared a secular state?
Answer:
Communalism was and continues to be one of the major challenges to democracy in our country The makers of our Constitution were aware of this challenge. That is why they chose the model of a secular state.

Class 10 Civics Chapter 4 Extra Questions And Answers Question 8.
Name a few leaders who worked for ending casteism in India.
Answer:
Political leaders and social reformers like Jotiba Phule, Mahatma Gandhi, Dr. Ambedkar and Periyar Ramaswami Naicker advocated and worked to establish a society in which caste inequalities are absent.

Class 10 Civics Chapter 4 Question Answer Question 9.
“Exclusive attention to caste can produce negative results also.”. Explain.
Answer:

• As in the case of religion, politics based on caste identity alone is not very healthy in a democracy.
• It can divert attention from other pressing issues like poverty, development and corruption.
  In some cases casteism leads to tensions, conflicts and even violence.

Gender Religion And Caste Class 10 Extra Questions Question 10.
What do you mean by the term ‘Secular’.
Answer:
It means being neutral or matters of faith and having no special preference to any religion. It involves giving freedom to people to follow religion of their own choice. The state treats every religion equally.

Gender Religion And Caste Class 10 Important Questions Question 11.
Define family laws.
Answer:
The family laws are related to families. They apply differently to different religions. They deal with family-related issues such as inheritance, marriage, adoption, divorce etc.

Gender Religion And Caste Class 10 Questions And Answers Question 12.
How can women’s representation be increased in politics?
Answer:

• One way to solve this problem is to make it legally binding to have a fair proportion of women in the elected bodies.
• This is what the Panchayati Raj has done in India. One-third of seats in local government bodies – in panchayats and municipalities-are now reserved for women.
• Now there are more than 10 lakh elected women representatives in rural and urban local bodies.
• Women’s organisations and activists have been demanding a similar reservation of at least one-third of seats in the Lok Sabha and the state assemblies for women.

Gender Religion And Caste Class 10 Questions And Answers Question 13.
Can religion be used positively in politics? How?
Answer:

• Gandhiji always preached for using the moral values of all the religions as a guide to the political system. He believed that all the religions have some belief system and the ethics. It should be used in politics as a guide.
• Ideas, ideals and values should have a place in politics. People should be able to voice their needs and interests as a religious community. Also, the leaders should regulate the religion to ensure that it is not used for discrimination and oppression.
• However, the use of religion in politics should be done with careful thought and analysis. No religious demand or interest should be raised if it is against any other religion.
• Religion should be used to bind the people together and not arouse feelings of distrust and suspicion.

Gender Religion And Caste Class 10 Questions And Answers Pdf Question 14.
Why is the work done by the males more visible than the work done by the females?
Answer:

• The work is generally divided on the basis of the gender of a person. The women of the family are supposed to do all the household work and the men are supposed to go out for work.
• The work done by women is generally unpaid for like cooking, cleaning, washing clothes and taking care of children. Also, no specific skill is required to do the household work.
• While the male members earn money for their work and some skills are needed for the work. Due to this, the work done by men is respected more in the society and hence, considered as more visible than the work done by females.

Class 10 Civics Chapter 4 Questions And Answers Question 15.
When does the problem of communalism become acute?
Answer:
Communalism creates an acute problem when:

• Religion is used in politics as an exclusive factor where people belonging to different religions are treated differently
• Demands of one religion are against the demands of another religion and there is feeling of distrust among the people of different religions
• Beliefs and ideas of one religion are shown to be superior to the beliefs and ideas of another religion.
• Various religious groups are in opposition to each other and the winning or defeat of a particular group is associated with respective religion’s winning or defeat.

Question 16.
Explain “political mobilization on communal line”.
Answer:

1. Communalism means promoting the ideas of one religion within a particular group and undermining the ideas of other religions. It becomes a problem when religion is used to divide the society.
2. It believes that people belonging to different religions form different communities and cannot live together as one nation.
3. Communalism in politics sometimes takes the shape of political mobilization on communal lines. It means that political leaders appeal to people of different religions to gain votes. It involves the use of sacred religious symbols and religious leaders to appeal to the people of that religion.
4. It attempts to bring all the people of one religion together. The political leaders pay special attention to the demands of one religion at the cost of the other religions.

Question 17.
What do you mean by caste inequalities?
Answer:

• Unlike gender and religion, the caste division is special to India. All societies have some kind of social inequalities and some form of division of labour.
• In most societies, occupations are passed on from one generation to another. Caste system is an extreme form of this.
• What makes it different from other societies is that in this system hereditary occupational division was sanctioned by rituals.
• Members of the same caste group were supposed to form a social community that practiced the same or similar occupation married within the caste group and did not eat with members from other caste groups.

Question 18.
“Caste and caste system in India have undergone great changes.” Explain.
Answer:

1. Caste and caste system in modern India have undergone great changes. With, economic development, large scale urbanization, growth of literacy and education, occupational mobility and the weakening of the position of landlords in the villages the old notion of caste hierarchy are breaking down.
2. Now, most of times in urban areas it does not matter much who is walking along next along next to us on a street or eating at the next table in a restaurant.
3. The Constitution of India prohibited any caste-based discrimination and laid the foundations of policies to reverse the injustices of the caste system.
4. If a person who lived century ago were to return to India, he/she would be greatly surprised at the change that has come about the country.

Question 19.
“Caste can take various form in politics.” How?
Answer:
Caste can take various forms in politics:

1. When parties choose candidates in elections, they keep in mind the caste composition of the electorate and nominate candidates from different castes so as to muster necessary support to win elections. When the governments are formed, political parties usually take care that representatives of different castes and tribes find a place in it.
2. Political parties and candidates in elections make appeals to caste sentiments to muster support. Some political parties are known to favour some castes and are seen as their representatives.
3. Universal adult franchise and the principle of one-person-one-vote compelled the political leaders to gear themselves up to the task of mobilizing and securing political support. It also brought new consciousness among the people of castes that were hitherto treated as inferior and low.

Question 20.
How does politics influence caste?
Answer:
It is not politics that gets caste-ridden, it is the caste that gets politicised. This takes several forms:

• Each caste group tries to become bigger by incorporating within it neighbouring castes or sub-castes which were earlier excluded from it.
• Various caste groups are required to enter into a coalition with other castes or communities and thus enter into a dialogue and negotiation.
• New kinds of caste groups have come up in the political arenas like ‘backward’ and ‘forward’ caste groups.
• Thus caste plays different kinds of roles in politics. In some ways, it is a routine factor that works all over the world mobilise social groups and communities in order to get their votes.
• In some situations, expression of caste differences in politics gives many disadvantaged communities the space to demand share of power. In this sense caste, politics has helped people from Dalits and OBC castes to gain better access to decision making. Several political and non¬political organisations have been demanding and agitating for the end of discrimination against particular castes, for more dignity and more access to land, resources and opportunities.

Question 21.
“Case continues to be very strongly linked to economic status in many important ways.” Explain.
Answer:
As the evidence from the National Sample Survey shows, caste continues to be very strongly linked to economic status in many important ways:

• The average economic status (measures by criteria like monthly consumption expenditure) of caste groups still follows the old hierarchy – the ‘upper’ castes are best off, the Dalits and Adivasis are worst off, and the backward castes are in between.
• Although every caste has some poor members, the proportion living in extreme poverty (below the official ‘poverty line’) is much higher for the lowest castes and much higher for the upper castes, with the backward castes once again in between.
• Although every caste has some members who are rich, the upper castes are heavily over-represented among the rich while the lower castes are severely under-represented.

Question 22.
Explain the concept of sexual division of labour.
Answer:

• Gender division does not mean the biological difference between men and women. It refers to the unequal roles assigned by the society to men and women.
• Boys and girls are brought up to believe that the main responsibility of women is housework and bringing up children.
• This is reflected in a sexual division of labour in most families: women do all work inside the home such as cooking, cleaning, washing clothes, tailoring, looking after children, etc. and men do work outside the home.
• It is not that men cannot do housework; they simply think that it is for women to attend to these things. When these jobs are paid for, men are ready to take up these works. Most tailors or cooks in hotels are men.
• Similarly, it is not that women do not work outside their home. Women fetch water and collect fuel in villages, they work in the fields, they often do shopping and are increasingly taking up paid jobs. But their work is not valued and does not get recognition.
• The result of this division of labour is that women have been confined to the private domain of family, while the public domain has been monopolized by the men.

Question 23.
“Women face disadvantage, discrimination and oppression in various ways.” Give some instances to support the statement.
Answer:
In our country, women still lag much behind men despite some improvement since independence. Ours is still male-dominated, patriarchal, society.

Women face disadvantages, discrimination and oppression in various ways:

The literacy rate among women is only 54 per cent compared to 76 per cent among men. Similarly, a smaller proportion of girl students go for higher studies. When we look at school results, girls perform as well as boys, if not better in some places. But they get dropped Out because parents prefer to spend their resources for their boys education than spending equally on their sons and daughters.

No wonder the proportion of women among the highly paid and valued jobs is still very small. On an average Indian woman works one hour more than an average male every day. Yet much of her work is not paid and therefore often not valued.

In many parts of India parents prefer to have sons and find ways to have the girl child aborted before she born. This has led to a decline in child sex ratio (number of girl child per thousand boys) in the country to merely 927.

There are reports of various kinds of harassment, exploitation and violence against women. Urban areas have become particularly unsafe for women. They are not safe even within their own home from beating and other forms of domestic violence.

The Equal Wages Act provides that equal wages should be paid to equal work. However, in almost all areas of work; women are paid less than men, even when both do exactly same work.

Question 24.
Write a note on communal politics and its consequences.
Answer:

• Communal politics is based on the idea that religion is the principal basis of social community. Communalism involves thinking along the following lines.
• The followers of a particular religion must belong to one community. Their fundamental interests are the same. Any difference that they may have is irrelevant or trivial for community life
• It also follows that people who follow different religions cannot belong to the same social community.
• If the followers of different religions have some commonalities these are superficial and immaterial.
• Their interests are bound to be different and involve a conflict.

Question 25.
How can you say that communalism can take various forms in politics?
Answer:
Communalism can take various forms in politics:

The most common expression of communalism is in everyday beliefs. These routinely involve religious prejudices, stereotypes of religious communities and belief in the superiority of one’s religion over other religions. This is so common that we often fail to notice it, even when we believe in it.

A communal mind often leads to a quest for political dominance of one’s own religious community. For those belonging to majority community, this takes the form of majoritarian dominance ‘For those belonging to the minority community, it can take the form of a desire to form a separate political unit

Political mobilisation on communal lines is another frequent form of communalism. This involves the use of sacred symbols, religious leaders, emotional appeal and plain fear in order to bring the followers of one religion together in the political arena. In electoral politics, this often involves special appeal to the interests or emotions of voters of one religion in preference to others.

Sometimes communalism takes its most ugly form of communal violence, riots and massacre. India and Pakistan suffered some of the worst communal riots at the time of the partition. The post-independence period has also seen large scale communal violence.

Question 26.
“India is a secular state”. Justify.
Answer:

There is no official religion of the Indian state. Unlike the status of Buddhism in Sri Lanka, that of Islam in Pakistan and that of Hinduism in Nepal till recently, our Constitution does not give a special status to any religion.

The Constitution provides to all individuals and communities freedom to profess, practice and propagate any religion, or not to follow any.

The Constitution prohibits discrimination on grounds of religion.

At the same time the Constitution allows the state to intervene in the matters of religion in order to ensure equality within religious communities. For example, it bans untouchability.

Understood in this sense secularism is not just an ideology of some parties or persons. This idea constitutes one of the foundations of our country.

Communalism should not be seen as a threat to some people in India. It threatens the very idea of India. That is why communalism needs to be combated. A secular Constitution like ours is necessary but not sufficient to combat communalism. Communal prejudices and propaganda needs to be countered in everyday life and religion-based mobilization needs to be countered in the arena of politics.

Question 27.
“The focus on caste in politics can sometimes give an impression that elections are all about caste and nothing else. But that is far from true.” Justify.
Answer:
The focus on caste in politics can sometimes give an impression that elections are all about caste and nothing else. That is far from true. Just consider these examples:

• No parliamentary constituency in the country has a clear majority of one single caste. So, every candidate and party needs to win the confidence of more than one caste and community to win elections.
• No party wins the votes of all the voters of a caste or – community. When people say that a caste is a vote bank’ of one party it usually means that about two-thirds of the voters of that community.
• The ruling party and the sitting MP or MLA frequently lose elections in our country. That could not have happened if all castes and communities were frozen in their political preferences.
• The voters have strong attachment to political parties which is often stronger than their attachment to their caste or community. People within the same caste or community have different interests depending on their economic condition.

Multiple Choice Questions
Four choices are given to the following questions.
Choose the correct answer

Question 1.
Ours is a …………………… society.
(a) Matriarchal
(b) Patriarchal
(c) Feminist
(d) Elders
Answer:
(b) Patriarchal

Question 2.
The literacy rate among women in India is:
(a) 54%
(b) 65%
(c) 48%
(d) 55%
Answer:
(a) 54%

Question 3.
The literacy rate among men in India is:
(a) 54%
(b) 65%
(c) 76%
(d) 80%
Answer:
(c) 76%

Question 4.
On an average an Indian woman works – how much more than an average man every day:
(a) 1 hour more
(b) 2 hours more
(c) 3 hours more
(d) 4 hours more
Answer:
(a) 1 hour more

Question 5.
Child sex-ratio in India is:
(a) 935
(b) 952
(c) 980
(d) 927
Answer:
(d) 927

Question 6.
Now, there are more than elected women representatives in rural and urban local bodies:
(a) 2 lakhs
(b) 5 lakhs
(c) 7 lakhs
(d) 10 lakhs
Answer:
(d) 10 lakhs

Question 7.
How many seats is local government bodies are now reserved for women?
(a) 1/3
(b) 2/3
(c) 3/4
(d) none
Answer:
(a) 1/3

Question 8.
India is a:
(a) Religious state
(b) Secular state
(c) Autocratic state
(d) None of these
Answer:
(b) Secular state

Question 9.
In 2001, population of STs in India was:
(a) 0.8%
(b) 16.2% .
(c) 19%
(d) 8.2%
Answer:
(d) 8.2%

Question 10.
Who are majority in India?
(a) Muslim
(b) Hindus
(c) Christians
(d) None of these.
Answer:
(b) Hindus

Question 11.
Shift of population from rural area to urban areas is called:
(a) Urbanisation
(b) Rural Migration
(c) Dwelling
(d) None of these
Answer:
(a) Urbanisation

Question 12.
BPL for rural areas was fixed at spending of:
(a) ₹ 454
(b) ₹ 550
(c) ₹ 327
(d) ₹ 800.
Answer:
(c) ₹ 327

Question 13.
BPL for urban areas was fixed at spending of:
(a) ₹ 800
(b) ₹ 327
(c) ₹ 550
(d) ₹ 454
Answer:
(d) ₹ 454.

Extra Questions for Class 10 Social Science

Check the below NCERT MCQ Questions for Class 10 Geography Chapter 3 Extra Questions and Answers Water Resources Pdf free download. https://ncertmcq.com/extra-questions-for-class-10-social-science/

Water Resources Class 10 Extra Questions Geography Chapter 3

Water Resources Class 10 Extra Questions And Answers Question 1.
Wherefrom the Brahmputra originates?
Answer:
From Tibet.

Class 10 Geography Chapter 3 Extra Questions And Answers Question 2.
In which direction does the Brahmaputra flow?
Answer:
The Brahmaputra flows in eastward direction parallel to the Himalayas.

Class 10 Geography Chapter 3 Extra Questions Question 3.
What does the Brahmputra do in Namecha Barwa?
Answer:
The Brahmputra reaching Namcha Barwa takes a U-turn and enters India in Arunachal Pradesh.

Water Resources Class 10 1 Mark Questions Question 4.
What is a river basin?
Answer:
A river basin is meant by the area which is drained by a single river system. This is also known as drainage basin.

Class 10 Geography Chapter 3 One Mark Questions Question 5.
Name two saltwater lakes on the eastern coast of India.
Answer:

1. The chilka-in Orissa.
2. The Pulicat-in Tamil Nadu.

Class 10 Geography Chapter 3 Extra Questions In Hindi Question 6.
In which states does the Brahmaputra flow in India?
Answer:

• Arunachal Pradesh,
• Assam.

Water Resources Class 10 Important Questions And Answers Question 7.
By which name the mainstream of Ganga is known in Bangladesh?
Answer:
Padma.

Water Resources Class 10 Questions And Answers Question 8.
When is the Ganga as Jamuna?
Answer:
In Bangladesh when the Brahmaputra joins the Ganga, it is known as Jamuna.

Class 10 Geography Chapter 3 Questions And Answers Question 9.
Where does the Jhelum fall into the Indus?
Answer:
A little over Mithankot.

Water Resources Class 10 Very Short Questions And Answers Question 10.
What is meant by the dendritic pattern of streams?
Answer:
The dendritic pattern of streams indicate the streams resembling like the branches of a tree.

Extra Questions Of Water Resources Class 10 Question 11.
Point out the prominent features of the Ganga-Brahmaputra delta.
Answer:

• It is the largest delta of the world.
• It is one of the most fertile areas of the world.
• It is a triangular-shaped area.
• It is a well-watered area.
• The lower part of this delta is marshy.
• Mangroves are found only in this place of the whole India.

Water Resources Class 10 Short Questions And Answers Question 12.
How would you differentiate between a glacier and a river?
Answer:

Glacier	River
1. Glaciers are in the solid form.	1. River are in liquid form.
2. Glaciers look like a mountain of ice.	2. Rivers may be seen flowing.
3. Glaciers move very slowly.	3. Rivers move with a greater speed
4. The movement of a glacier is not discernible.	4. The movement of a river is easily discernible.

Class 10 Water Resources Extra Questions Question 13.
How the lakes are formed?
Answer:

• Lakes are formed in the mountainous area when the glaciers block the valleys and large amount of water is collected in that place.
• The violent movements of the earth, like the earthquakes, also create lakes when the depressions formed on the crust of the earth are filled with rainwater.
• Human beings also form lakes for various purpose.

Water Resources Class 10 Questions And Answers Pdf Question 14.
What is meant by the Indus water treaty?
Answer:
Indus water treaty is a treaty between India and Pakistan. This treaty is about the sharing of the waters of the Indus system. According to this treaty, India can use only 20% of the total of the water carried by the Indus river system.

Class 10 Geography Chapter 3 Important Questions Q. 15.
Which are the important peninsular riv¬ers of India?
Or
Give a brief account of the different peninsu¬lar rivers of India.
Answer:
The Narmada: It rise from Amarkantak in Madhya Pradesh. It flows west-southward in a trough for a distance about 1300 km. The Narmada gorge in the marble rocks of Madhya Pradesh is very famous for its beauty.

The Tapi: It rises from the Betul district of Madhya Pradesh. It flows in a trough parallel to the Narmada. However, it is smaller in size than of the Narmada.

The Godavari: It is also known as the Dakshin Ganga and Vridha Ganga. It is the largest among the peninsular rivers of India. It rises in Nashik district of Maharashtra. Its length is about 15000 km. It drains into the Bay of Bengal.

The Mahanadi: It rises in Chattisgarh and flows through Orissa and reaches the Bay of Bengal.

The Krishna: It rises from the spring near Mahabaleshwar. It flows for nearly about 1400 km. Its drainage basin in shared by Maharashtra, Karnataka and Andhra Pradesh.

The Kaveri: It rises in the Brahmagir ranges of the Western Ghats. It flows over 800 km. Near the Kaveripatnam, it reaches the Bay of Bengal.

Question 16.
What is the reason of the water pollution? How the pollution level can be reduced?
Or
Suggest some measures to reduce the pollution of water.
Answer:
Water pollution indicates that the water is not pure and safe for the health. Today many factors are causing the water pollution. It is very dangerous for health as well as for the environment. The large number of the dead fishes found in Yamuna at Agra proved it. Factories, specially the chemical industries, paper mills, sugar mills, tanneries etc. are causing the water to be polluted. The disposal of sewage of urban areas into the rivers also lead to this pollution.

As for example, the Najafgarh Nala in Delhi may be taken. Water is also being polluted by the use of pesticides and fertilizers in the nearby fields.
To reduce the pollution level, the following steps should be taken:

• The effluents from the factories should not be allowed to fall into the rivers.
• No chemical industry, paper mill, sugar mill should be allowed to stagnate their effluents on land at any cost. So that it do not pollute the underground water through seepage.
• Effluents of the mills and the factories should be scientifically treated and recycled to be used again.
• Sewage should be treated and diverted to irrigate the fields and the wastelands.
• Oil spills from tankers must not be allowed to enter any water form or river. In fact being a little more aware and taking care of otherwise looking small matters, magic can be created. It would surely make the rivers and other water bodies pollution-free. It will also do magic for our environment.

Glacier:

1. Glaciers are in solid form.
2. Glaciers look like a mountain of ice.
3. Glaciers move very slowly.
4. The movement of a glacier is not discernible.

Multiple Choice Questions

1. Choose the right answer from the four alternatives given below;

Question 1.
The river Indus rises from the following:
(a) Mansarovar
(b) Gangotri
(c) Nasik
(d) Mahabaleswar.
Answer:
(a) Mansarovar

Question 2.
The Ganga is also known as:
(a) Krishna
(b) Bhagirathi
(c) Narmada
(d) Kaveri
Answer:
(b) Bhagirathi

Question 3.
The following is a peninsular riven
(a) The Ganga
(b) The Tapi
(c) The Indus
(d) The Brahmaputra.
Answer:
(b) The Tapi

Question 4.
The following is the largest peninsular river:
(a) Mahanadi
(b) Krishna
(c) Godawari
(d) Narmada.
Answer:
(c) Godawari

Question 5.
The following is the range from where the river Tapi rises:
(a) Satpura
(b) Aravalli
(c) Vindhya
(d) None of these.
Answer:
(d) None of these.

Map Skills

Question 1.
On the outline may of India, show major dams.
Answer:

Question 2.
On the outline map of India locate the following: Satluj, Damodar, Krishna, Godavari, Mahanadi and Brahmputra.
Answer:

Extra Questions for Class 10 Social Science

Check the below NCERT MCQ Questions for Class 10 Economics Chapter 5 Extra Questions and Answers Consumer Rights Pdf free download. https://ncertmcq.com/extra-questions-for-class-10-social-science/

Consumer Rights Class 10 Extra Questions Economics Chapter 5

Extra Questions For Class 10 Economics Chapter 5 Question 1.
Which is the apex body of the consumer courts in our country?
Answer:
The National Consumer Commission.

Consumer Rights Class 10 Extra Questions Question 2.
Which is the most important consumer court?
Answer:
The District forum.

Consumer Rights Class 10 Questions And Answers Question 3.
In which year the Consumer Protection Act was enacted?
Answer:
In 1986.

Class 10 Economics Chapter 5 Mcq With Answers Question 4.
By which name was the BIS earlier known as?
Answer:
BIS was earlier known as the Indian Standards Institution.

Consumer Rights Class 10 Important Questions Question 5.
Where is the headquarter of the BIS?
Answer:
At New Delhi.

Consumer Rights Extra Questions Question 6.
What is DMI?
Answer:
DMI stands for the Directorate of Marketing.

Consumer Rights Class 10 Extra Questions And Answers Question 7.
Where was the Codex Alimentarious Commission Intelligence created?
Answer:
In 1963.

Consumer Rights Questions And Answers Question 8.
For what does ISO stand?
Answer:
ISO standas for the International Organisation for Standardisation.

Class 10 Economics Chapter 5 Questions And Answers Question 9.
When was the ISO established?
Answer:
In 1947.

Class 10 Economics Chapter 5 Important Questions Question 10.
What are the four basic consumer rights?
Answer:

1. Choice,
2. Information,
3. Safety,
4. Right to be heard.

Consumer Rights Important Questions Question 11.
When were the four basic consumer rights recognised?
Answer:
In 1962.

Questions On Consumer Rights Class 10 Question 12.
When is the World Consumer Rights Day celebrated?
Answer:
On 15th of March every year.

Cbse Class 10 Economics Chapter 5 Mcq Question 13.
Is it necessary to take professional help from a lawyer to file a complaint in the consumer court?
Answer:
No.

Cbse Class 10 Chapter Consumer Rights Objective Questions And Answers Question 14.
How many district courts are there. In our country?
Answer:
About 500.

Class 10 Chapter 5 Extra Questions Question 15.
In which country did the first consumer movement begin?
Answer:
In England.

Question 16.
Who is called as the father of consumer movement?
Answer:
Ralph Nadar.

Question 17.
Describe any four rights of the consumers.
Answer:

1. Right to be informed,
2. Rights to choose,
3. Right to seek redressal,
4. Right to represent.

Question 18.
For what the abbreviations APL and BPL stand?
Answer:
APL: Above Poverty Line.
BPL Below Poverty Line.

Question 19.
Where is International Organisation for standardization located
Answer:
Geneva.

Question 20.
On which day does India observe the National Consumer Day?
Answer:
24th December.

Question 21.
Write down the advantages of public distribution system.
Answer:
The public distribution system is very helpful preventing hoarding, black-marketing, overcharging. In addition to all these it also ensures food security to the poor.

Question 22.
What is meant by Agmark?
Or
Write down the functions of Agmark.
Answer:
Agmark is implemented under the Agricultural Product Act, 1937. This act was amended in 1986. Agmark is a scheme run by the Directorate of Marketing and Intelligence in the Ministry of Agriculture of the Government of India. Products like honey masala, etc. carry this AGMARK as the sign of purity.

Question 23.
What are the legal formalities for filing a complaint against a trader?
Answer:
There is no legal formalities for filing a complaint against a trader or a manufacturer in a consumer court. All one has to do is to write his or her complaint on a plain paper and attach the supporting documents like guarantee or warrantee card and cash memo and one can file this very simple complaint in a consumer court. Also there is no need to take any professional help from a lawyer as one can plead the case by oneself.

Question 24.
What do you know about the ISO.
Answer:
The ISO stands for the International Organization for Standardization. It is located in Geneva. It serves to provide a common reference standard at the international level. It is a non-governmental organisation. It was established in 1947. ISO’s work results in international agreements.

These are published as international standards. ISO 9000, ISO 6000, ISO 14000 and the like, indicate specific levels of standards for a particular industry or group of products or institutions.

Question 25.
What do you know about Codex Alimentarius Commission?
Or
Write down the functions of the Codex Alimentarius Commission.
Answer:
The Codex Alimentarius Commission was created in 1963. It is an international body for setting international food standards. This commission was actually created by the Food and Agriculture Organisation (FAO) and World Health Organisation (WHO). This commission is located in Rome, Italy.

The works of Codex Alimentarius Commission:

• It develops food standards.
• Prepares guidelines and codes of practices for production.
• Prepares guidelines and codes also for the international trade in food products.

Question 26.
Mention the organizations that provide certification of standardization in India.
Answer:
To protect the consumers from lack of quality and varying standards of goods; the Government has set mainly two institutions

1. Bureau of Indian Standards (BIS)
2. AGMARK, BIS caters to the industrial and consumer goods. On the other hand, Agmark is meant for the agricultural products.

Question 27.
Name the consumer courts at the district, state and national levels.
Answer:
Levels Consumers Courts

1. District District court
2. State State Consumer Commission
3. National consumer commission.

Question 28.
Present a brief sketch on the history of the consumer movement.
Answer:
Consumer protection is not a new concept for India as references to the protection of consumer’s interests have also been presented in Kautilya’s Arthashastra Kautilya in his Arthashastra has given a detailed sketch of how consumers interests should be protected against the exploitation by trade and industry, underweight and measurement, adulteration. Punishment for these offences were also made in Kautilya’s Arthashastra.

However in recent era, the modern organised and systematic movement to safeguard the interest of consumers has developed in the late 1980s and early 1990s when the Indian Economy opened up its door for liberalisation and globalisation. At the world level, first consumer movement began in England after the II World War.

However, the modern declaration about the consumer’s rights was first:

Rights of safety: The Consumer Protection Act of 1986 protects the consumers against the marketing of goods and services hazardous to their life and property.

Rights of information: This Act provides the consumer every right of information. It includes quality, quantity potency purity standard and also the price of the goods.

Right to choose: This Act of 1986 provides assurance of access to variety Of goods and services at competitive price. By this act the consumer is assured of satisfactory quality and service at a fair price.

Right to be heard: This Act clearly states that the consumer’s interests should receive due consideration at appropriate forums relating to consumer welfare.

Right to seek redressal: The Act of 1986 provides the right to seek redressal against unfair trade practices and the exploitation of consumers and rights to fair settlement of grievances. Act also includes the rights to knowledge about goods and issues relating to consumers welfare.

Question 29.
Mention and discuss numerous measures with regard to the protection of consumers interest.
Answer:
The following are measures with regard to the protection of consumers interests.

• The legislative measures include enactment of the Consumer Protection Act.
• The administrative measures include PDS which distributes essential commodities to the people directly.
• On the other hand technical measures consist of the standardization of the products.

To protect the rights of the consumers the Government of India has enacted the Consumer Protection Act in 1986. This Act provides for the establishment of Consumer Disputes Redressal Agencies at district, state and also at national levels. This Act has led to setting up of separate Department of Consumer Affairs in central/ and state governments, which focus exclusively on the rights of the consumers as enshrined in the Act.

Also there are no legal formalities for filing the complaint. One can write the complaint on a plain paper and attaching supporting documents like guarantee or warantee card and cash memo with the complaint can submit it in the district consumer court. Consumer courts have settled nearly 77% of the cases.

Moreover, Indian Government has taken the following steps to protect the rights of a consumer

Apart from ensuring food security to the poor as a part of certain administrative measures, the Indian Government has also started public distribution system to prevent hoarding, black marketing and overcharging by traders.

The other important measure taken by the Government to protect the rights of a consumer is standardisation of products. It protects the consumers from lack of quality:

The Government of India has established the Bureau of Indian Standards to make sure about the quality of a product.

While BIS caters to the industrial and consumer goods, the Agmark is meant for the agricultural products.

Agmark is implemented under the Agricultural Produce Act, 1937. This Act was again amended in 1986.

For setting international food standards, there is a similar body called Codex Alimentarious Commission. This commission was created in 1963 by the Food and Agriculture Organisation (FAO) and World Health Organisation (WHO).

Question 30.
What are various ways in which a consumer is exploited?
Answer:
A consumer is exploited by the traders in various ways, some very common ways of this exploitation are the following
Underweight and under measurements: It is a very common practice by the traders not to weigh and measure the things properly and correctly.

Substandard quality: Many of the times goods sold are substandard quality. For example, selling of expired medicines and supply of deficiency or defective home appliances have generally become the regular grievances of consumers.

High Price: Very often the traders charge a price higher than the prescribed retail price

Duplicate articles: Many times in the name of genuine parts and goods, fake and duplicate items are sold to the consumers.

Adulteration: In costly items like ghee, oil, spices etc. adulteration is very commonly practised to make higher profit in a undue manner. It makes the customers lose their money as well as their health.

Lack of safety devices: Many of the times electrical devices and various electronic goods are sold without proper safeguard.

Unsatisfactory after-sale services: Many of the times suppliers do not provide the satisfactory after-sale services despite proper payments. It creates unnecessary tension to the customers.

Objective Type Questions

1. Put (✓) or (✗) before the following sentences

Question 1.
Codex International is located in Rome.
Answer:
(✓)

Question 2.
Rome is the capital of United Kingdom.
Answer:
(✗)

Question 3.
BIS was earlier known as ISCO.
Answer:
(✗)

Question 4.
ISO was established in 1947.
Answer:
(✓)

Question 5.
ISO is located in Geneva.
Answer:
(✓)

Question 6.
The consumers have the right to be protected against marketing of goods and services.
Answer:
(✓)

Question 7.
You cannot file your complaint to the consumer court without legal support.
Answer:
(✗)

Question 8.
You yourself can plead your case in the consumer court.
Answer:
(✓)

Question 9.
There are about 200 district consumer courts in our country
Answer:
(✗)

Question 10.
National Consumer Commission is located in Pune.
Answer:
(✗)

Question 11.
In India the concept of consumer protection is absolutely new.
Answer:
(✗)

Question 12.
The level of consumer consciousness in our country is generally low.
Answer:
(✓)

2. Match the following list

List A	List B
(i) National Consumer Commission	Rome
(ii) Codex Alimentarius Commission	Geneva
(iii) International Organisation for Standardisation	Delhi
(iv) Bureau of Indian Standards	New Delhi

Answer:

List A	List B
(i) National Consumer Commission	Delhi
(ii) Codex Alimentarius Commission	Rome
(iii) International Organisation for Standardisation	Geneva
(iv) Bureau of Indian Standards	New Delhi

3. Fill up the following blanks with suitable words:

(i) In India liberalization of economy began in early…………………………..
Answer:
1990s.

(ii)The Consumer Protection Act was enacted in …………………………. .
Answer:
1986.

(iii)Agricultural Product Act, 1937, was amended in …………………………. .
Answer:
1986.

(iv) Codex Alimentarious Commission was created in…………………………. .
Answer:
1963.

Extra Questions for Class 10 Social Science