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On this page, you will find The Fundamental Unit of Life Class 9 Notes Science Chapter 5 Pdf free download. CBSE NCERT Class 9 Science Notes Chapter 5 The Fundamental Unit of Life will seemingly help them to revise the important concepts in less time.

CBSE Class 9 Science Chapter 5 The Fundamental Unit of Life

The Fundamental Unit of Life Class 9 Notes Understanding the Lesson

1. Robert Hooke: In 1665, he discovered cell in a thin slice of cork (bark of cork tree) by using a self designed microscope. The structure consisted of many little compartments which resembled the structure of a honeycomb. He called boxes as ‘cell’ which is Latin word for ‘a little room’.

2. Leeuwenhoek: In 1674, discovered the free-living cells in pond water for the first time by using an improved microscope.

3. Robert Brown: In 1831, discovered the nucleus in the cell.

4. Piirkinje: In 1839, coined the term ‘protoplasm’ for the fluid substance of the cell.

5. Schleiden (1838) and Schwann (1839): Put forth the cell theory, which said that:

• all the plants and animals are composed of cells and
• cell is the basic unit of life.

6. Virchow: In 1855, expanded the cell theory by suggesting ‘Omni cellula-e-cellula’ which means all cells arise from pre-existing cells.

7. Unicellular organisms: Organisms which have only a single cell, e.gAmoeba, Paramecium, Chlamydomonas, bacteria, etc.

8. Multicellular organisms: Organisms which consist of more than one cell e.g., Plants, animals, fungi, etc.

9. Cell division: It is the process by which a cell divides to form new cells. This supports the fact that, all cells arise from the existing cells.

10. The shape and size of cells are related to the specific function they perform: Amoeba can change its shape as per the conditions or its need whereas for most of the other cases, the cell shape is more or less fixed, e.g., nerve cells have a typical shape.

11. Division of Labour: In all multicellular organisms there is a division of labour. This means that different parts of the body perform different functions. For example, the stomach helps in digestion; blood is pumped by the heart, etc. Division of labour can also be seen within a single cell.

12. Three main parts of a cell: Most cells (excluding bacteria) have three main parts:

• Plasma membrane/Cell Membrane
• Nucleus
• Cytoplasm

13. Plasma Membrane or Cell Membrane

• It is the outermost covering of the cell.
• It separates the contents of the cell from its external environment.
• It is mainly composed of lipids and proteins.
• It is called selectively permeable as it permits the entry and exit of only some materials in and out of the cell.

14. Diffusion: The movement of a substance from a region of its high concentration to the region of its low concentration is called diffusion. Diffusion helps in gaseous exchange between the cells as well as the cell and its external environment.

15. Osmosis: The spontaneous movement of water molecules from a region of its high concentration to the region of its low concentration through a selectively permeable membrane is called osmosis.

Effect on animal cell or a plant cell put into a solution of sugar or salt in water

Kind of solution	Nature of surrounding medium	Effect on cell	Result
Hypotonic solution	Medium surrounding the cell has a higher water concentration than the cell (outside solution is very dilute).	Water will enter the cell by osmosis.	Cell is likely to swell up.
Isotonic solution	Medium surrounding the cell has exactly the same water concentration as the cell.	There is no overall movement of water.	Cell will stay the same size.
Hypertonic solution	Medium surrounding the cell has a lower concentration of water than the cell (very concentrated solution).	Cell will lose water by osmosis.	Cell will shrink.

16. Cell Wall

• It is a rigid outer covering which lies outside the plasma membrane.
• It is made of cellulose which provides structural strength to plants.
• The shrinkage or contraction of the contents of the cell away from the cell wall when a living plant cell loses water through osmosis is known as plasmolysis.

17. Nucleus

• It is a dark coloured, spherical or oval, dot-like structure near the centre of each cell.
• It is the control centre of the cell as it controls all the activities of the cell.
• It has a double-layered covering called nuclear membrane.
• The nuclear membrane has pores which allow the transfer of materials from inside the nucleus to its outside, that is, to the cytoplasm.
• The nucleus plays a central role in cellular reproduction (process by which a single cell divides and forms two new cells).
•  Nucleus along with the environment directs the chemical activities of the cell to determine the way the cell will develop and the form it will exhibit at maturity.
• Nuclear region of the cell may be poorly defined due to the absence of a nuclear membrane in some organisms like bacteria. Such an undefined nuclear region containing only nucleic acids is called a nucleoid.

18. Chromosomes

• The nucleus contains chromosomes, which are visible as rod-shaped structures only when the cell is about to divide.
• Chromosomes contain information for inheritance of features from parents to next generation in the form of DNA (Deoxyribo Nucleic Acid) molecules.
• Chromosomes are composed of DNA and protein.

19. Genes
Functional segments of DNA are called genes.
Chromatin Material:

• DNA is present as part of chromatin material in the cells which are not dividing.
• Chromatin material is visible as entangled mass of thread-like structures.
• Chromatin material gets organised into chromosomes, when the cell is about to divide.

20. Types of organisms on the basis of the nature of nucleus and nuclear membrane

Prokaryotes	Eukaryotes
(i) Organisms whose cells lack a well defined nuclear membrane.	(i) Organisms with cells having a well defined nuclear membrane.
(ii) They lack membrane bound cell organelles.	(ii) They have membrane bound cell organelles.
(iii) Size is generally small (1-10 pm).	(iii) Size is generally large (5-100 pm).
(iv) Have a single chromosome.	(iv) Have more than one chromosome.

20. Cytoplasm

• It is the fluid content enclosed by the plasma membrane.
• It contains many specialised cell organelles.

21. Cell Organelles
Cell organelles are parts of the cell which are specialised for carrying out one or more vital functions, analogous to the organs of the human body.

22. A. Endoplasmic Reticulum (ER)
(i) Consists of a large network of membrane-bound tubes and sheets which appear as long tubules or round or oblong bags (vesicles).

(ii) ER serves as channels for the transport of materials (especially proteins) between various regions of the cytoplasm or between the cytoplasm and the nucleus.

(iii) It also functions as a cytoplasmic framework providing a surface for some of the biochemical activities of the cell.

(iv) ER are of two types:
Rough endoplasmic reticulum (RER) and
Smooth endoplasmic reticulum (SER).

(v) Rough endoplasmic reticulum

• It looks rough as it has particles called ribosomes attached to its surface. Ribosomes are the site of protein synthesis.

(vi) Smooth endoplasmic reticulum

• It helps in the manufacture of fat molecules, or lipids, important for cell function.
• Some proteins and lipids made by SER help in building the cell membrane and this process is known
  as membrane biogenesis.
• Helps in detoxifying many poisons and drugs in the liver cells of the group of vertebrates.

B. Golgi Apparatus

• First described by Camillo Golgi.
• It has membrane-bound vesicles arranged approximately parallel to each other in stacks called cisterns.
• They constitute another portion of a complex cellular membrane system as their membranes often have connections with the membranes of ER.
•  Its functions include storage, modification and packaging of products in vesicles.
• Golgi apparatus packages and dispatches the material synthesised near the ER to various targets inside and outside the cell.
• They are also involved in the formation oflysosomes.

C. Lysosomes

• They are membrane-bound sacs filled with digestive enzymes made by RER.
• They are waste disposal system of the cell as they help to keep the cell clean by digesting any foreign material as well as worn-out cell organelles.
• Lysosomes have powerful digestive enzymes capable of breaking down all organic materials.
• Lysosomes are also known as the ‘suicide bags’ of a cell because if the cell gets damaged during disturbance in cellular metabolism, the lysosomes may burst and its enzymes digest their own cell.

D. Mitochondria

• Also known as the powerhouses of the cell as the energy required for various chemical activities needed for life is released by mitochondria in the form of Adenosine triphosphate – ATP (ATP is known as the energy currency of the cell).
• Mitochondrion is a double-membrane structure whose outer membrane is very porous while the inner
  membrane is deeply folded to form cristae. Cristae are folds which create a large surface area for ATP’ generating chemical reactions.
• Mitochondria have their own DNA and ribosomes so they can make some of their own proteins.

E. Plastids

• Plastids are present only in plant cells and are of two types – chromoplasts (coloured plastids) and leucoplasts (white or colourless plastids).
• Chlorophyll containing plastids are known as chloroplasts and help in photosynthesis.
• Leucoplasts store starch (amyloplast), oils (elaioplasts) and protein granules (aleuroplasts).
• The plastids internally consist of numerous membrane layers embedded in a material called the stroma.
• Plastids have their own DNA and ribosomes so they can make some of their own proteins.

F. Vacuoles

• Vacuoles are storage sacs for solid or liquid contents like amino acids, sugars, various organic acids and some proteins.
• Small-sized vacuoles are present in animal cells while plant cells have very large vacuoles. A large central vacuole may occupy 50-90% of the cell volume in some plant cells.
• The vacuoles are full of cell sap and provide turgidity and rigidity to the cell in plant cells.
• Food vacuole found in Amoeba contains the food items that the Amoeba has consumed.
• Contractile vacuole found in some unicellular organisms help in expelling excess water and some wastes f from the cell.

Class 9 Science Chapter 5 Notes Important Terms

Unicellular organisms: They are single-celled organisms, e.g., Amoeba, Paramecium, Chlamydomonas, bacteria, etc.

Multicellular organisms: They are composed of more than one cell, e.g., plants, animals, fungi, etc. Diffusion: The movement of a substance from a region of its high concentration to the region of its low concentration is called diffusion.

Osmosis: The spontaneous movement of water molecules from a region of its high concentration to the region of its low concentration through a selectively permeable membrane is called osmosis.

Hypotonic solution: If the medium surrounding the cell has a higher water concentration than the cell i.e., outside solution is very dilute, then it is called a hypotonic solution.

Isotonic solution: If the medium surrounding the cell has exactly the same water concentration as the cell, then it is called isotonic solution.

Hypertonic solution: If the medium surrounding the cell has a lower concentration of water than the cell i.e., very concentrated solution, then it is called hypertonic solution.

Plasmolysis: The shrinkage or contraction of the contents of the cell away from the cell wall when a living plant cell loses water through osmosis is known as plasmolysis.

Genes: Functional segments of deoxyribonucleic acid (DNA) are called genes.

Prokaryotes: The single celled organisms which lack a well-defined nuclear membrane are called prokaryotes.

Eukaryotes: The single celled or multicellular organisms which have a well defined nuclear membrane are called eukaryotes.

Membrane biogenesis: Some proteins and lipids made by SER help in building the cell membrane and this process is known as membrane biogenesis.

Amyloplast: The starch containing leucoplasts are called amyloplast.

Elaioplast: The oil containing leucoplasts are called elaioplasts.

Aleuroplast: The protein containing leucoplasts are called aleuroplasts.

On this page, you will find Areas related to Circles Class 10 Notes Maths Chapter 12 Pdf free download. CBSE NCERT Class 10 Maths Notes Chapter 12 Areas related to Circles will seemingly help them to revise the important concepts in less time.

CBSE Class 10 Maths Chapter 12 Notes Areas related to Circles

Areas related to Circles Class 10 Notes Understanding the Lesson

1. Circle: Circle is set of all points in a plane which are at the fixed distance from a fixed point i.e., centre. Centre: Mid-point of a circle is called centre of a circle.

2. Radius: The distance between the centre of a circle to the circumference of the circle.
It is denoted by r or R.

3. Chord: A line segment which joins the two points in the circumference of the circle.

4. Diameter: It is the longest chord which passes through the centre of a circle. It is denoted by d or D.
Diameter = 2 x radius
\(\text { Radius }=\frac{\text { Diameter }}{2}\)

5. Circumference of a Circle (or Perimeter)
A perimeter is a path that surrounds a two dimensional shape.
The perimeter of a circle is called its circumference. Circumference
\(\frac{\text { Circumference }}{\text { Diameter }}=\pi\)
Circumference = n x diameter = π x 2r = 2πr
or
The value of π is \(\frac{22}{7}\) or 3.14 (approximately)

6. Arc: An arc is the part of the circumference of a circle.
An arc AB is denoted as \(\widehat{\mathrm{AB}}\)

Length of arc AB is l \(\widehat{\mathrm{AB}}\) or l.
Length of an arc of a sector of angle
\(\theta=\frac{2 \pi r \theta}{360^{\circ}}\)

7. Sector: The portion (or part) of circular region enclosed by two radii and the corresponding arc is called a sector of the circle.

8. Minor and Major sector of the circle: Shaded region OAPB is called sector or minor sector of a circle with centre O.
∠AOB is called angle of the sector.

And OAQB is called major sector.
Angle of major sector = 360° – ∠AOB.

9. Area of Circle

Let r be the radius of circle. If we cut the circle in sectors and arrange then we see this figure like a rectangle whose length is \(\frac{1}{2}\) 2πr = πr and breadth is r.
Hence,
Area of circle = Area of rectangle
= l x b = \(\frac{1}{2}\) 2πr = r
Area of circle = πr²

10. Segment: The portion or part of a circular region enclosed between a chord and the corresponding arc is called a segment of the circle.
The shaded region APB is the minor segment.
And the region AQB is the major segment.
Area of circle = πr²
Area of the sector of an angle \(\theta=\frac{\pi r^{2} \theta}{360^{\circ}}\)

Area of major sector = Area of circle – Area of minor sector
Area of minor segment = Area of sector – Area of ΔOAB\(\frac{\pi r^{2} \theta}{360^{\circ}}\)– area of ΔOAB
Area of major segment = Area of circle – Area of minor segment

11. Area of Combinations of Plane Figures
In our daily life we have observed various plane figures which are combinations of two or more figures and i also in the form of various interesting designs like flower beds, curtains, drain covers, window designs, ] designs on table covers.  To calculate areas of such figures, we field the area of shapes used and then and/subtract as per need.

On this page, you will find Structure of the Atom Class 9 Notes Science Chapter 4 Pdf free download. CBSE NCERT Class 9 Science Notes Chapter 4 Structure of the Atom will seemingly help them to revise the important concepts in less time.

CBSE Class 9 Science Chapter 4 Notes Structure of the Atom

Structure of the Atom Class 9 Notes Understanding the Lesson

1. Discovery of electron: Study of cathode rays.

• On electrical discharge through gases at very low pressure, cathode rays are produced.
• Cathode rays move in straight line.
• Cathode rays have some mechanical energy.
• Cathode rays consist of negatively charged particles, i.e., electrons.

2. Electron: An electron is the sub-atomic or fundamental particle which carries one unit negative charge.
It is represented by e^–.
Mass of one electron = 9.11 x 10^-31 kg.
Charge of one electron = – 1.6 x 10^-19 C.

3. Proton: Discovered by Goldstein (1886) anode ray or canal ray experiment.
Mass of proton = 1.67 x 10^-24 kg.
One proton is 1840 times heavier than electron.
Charge on proton = + 1.6 x 10^-19 C.

4. Thomson’s model of an atom
He proposed that:

• An atom consists of a uniform sphere of positive electricity in which the electrons are distributed more or less uniformly.
• The negative and the positive charge are equal in magnitude. Thus, the atom as a whole is electrically neutral.

5. Rutherford’s model of an atom
Rutherford observed that:

• Most of the a-particles (nearly 99%) passed through the gold foil undeflected.
• Some of the a-particles (about one in every 20,000) were deflected by small angles.
• A few particles (1 in about 10⁶) were either deflected by very large angles or were actually reflected back along their path.

In order to explain the observation of his scattering experiment, Rutherford assumed that the solid gold foil consists of layers of individual atoms touching each other so that there is hardly any empty space between them. Rutherford explained his observation as follows:

• Most of the space inside the atom is empty because most of the a-particles passed through the gold foil without getting deflected.
• Very few particles were deflected from their path, indicating that the positive charge of the atom occupies very little space
• A very small fraction of a-particles was deflected by 180°, indicating that all the positive charge and mass of the gold atom were, concentrated in a very small volume within the atom.

On the basis of his experiment, Rutherford put forward the nuclear model of an atom, which had the following features:

• There is a positively charged centre in an atom called the nucleus. Nearly all the mass of an atom resides in the nucleus.
• The electrons revolve around the nucleus in circular paths.
• The size of the nucleus is very small as compared to the size of the atom.

6. Drawbacks of Rutherford’s model of the atom
Rutherford’s model could not explain the stability of the atom. This is because according to Rutherford’s model, an atom consists of a small heavy positively charged nucleus in the centre and the electrons revolve around it.

However, whenever a charged particle like an electron revolves around a central force like that of a nucleus, it loses energy continuously in the form of radiations. Thus, the orbit of the revolving electron will keep on becoming smaller and smaller and ultimately the electron should fall into the nucleus.

7. Discovery of Neutrons
Neutron may be defined as subatomic particle which had no charge and a mass nearly equal to that of proton:

• Mass of neutron = 1.676 x 10^-24
• Charge of neutron = 0 (zero).

8. Bohr’s atomic model

• Electron revolves around nucleus only in certain selected circular orbits with definite energies and are called energy shells or energy levels.
• While revolving around the nucleus in an orbit, an electron does not lose energy nor does it gain energy.
• Different shells or orbits are numbered as 1, 2, 3, 4…………………… or designated as K, L, M, N……………….
• Every orbit is associated with a fixed amount of energy, so on gaining a certain amount of energy e~, jumps to the higher orbit.

9. How are electrons distributed in different orbit (shells)?
Answer:
The distribution of the electrons in the shells is known as electronic configuration. It is based on certain guide­lines or rules given by Bohr and Bury. This is known as Bohr-Bury scheme. According to this scheme,

1. The maximum number of electrons present in a shell is given by the formula 2n², where ‘n’ is the orbit number of energy level index, 1, 2. 3,………………… Hence the maximum number of electrons in different shells are as follows:

• First orbit or K-shell will be = 2 x 1² = 2,
• Second orbit or L-shell will be = 2 x 2² = 4,
• Third orbit or M-shell will be = 2 x 3² = 18,
• Fourth orbit or N-shell will be = 2 x 4² = 32 and so on.

3. The maximum number of electrons that can be accommodated in the outermost orbit is 8.

4. Electrons are not accommodated in a given shell, unless the inner shells are filled. That is, the shells are filled in a step-wise manner.
Atomic structure of first eighteen elements is shown schematically in the figure given below.

10. Valency
The electrons present in the outermost shell of an atom are known as the valence electrons.
From the Bohr-Bury scheme, the outermost shell of the an atom can accommodate a maximum of 8 electrons. The combining capacity or valency of elements having a completely filled outermost shell is zero. Inert elements, like helium atom has two electrons in its outermost shell and all other elements have atoms with eight electrons in their outermost shell.

The combining capacity of the atoms of other elements was explained in terms of their tendency to attain a fully-filled outermost shell (stable octect or dulpet). The atoms which do not have their outermost shell fully filled enter into bond formation with other atoms in order to achieve an octet (or duplet) of electrons in their outermost shells. They do so either by sharing, losing or gaining electrons.

If the number of electrons in the outermost shell of an atom is close to its full capacity, then valency is determined in a different way.

11. Atomic number (Z)
The number of unit positive charges present in the nucleus of an atom is known as atomic number of the element.
It is denoted by the symbol Z.
Atomic no. (Z) = No. of protons = No. of electrons.
For example: Hydrogen, Z = 1 because in hydrogen atom, only one proton is present in the nucleus.
Similarly, for carbon Z = 6.

12. Mass number
The mass number is defined as the sum of the total number of protons and neutrons present in the nucleus of an atom. For example, mass of carbon is 12u because it has 6 protons and 6 neutrons, 6u + 6u = 12u. Similarly, the mass of aluminium is 27u because it has 13 protons and 14 neutrons.

The atomic number, mass number and symbol of the element are to be written as:

For example: Nitrogen is written as \({ }_{7}^{14} \mathrm{N}\).

13. Isotopes
The different atoms of the same element having same atomic number but different mass numbers.
For example: Hydrogen atom, has three isotopes, namely protium \(\left({ }_{1}^{1} \mathrm{H}\right)\), deuterium and tritium \(\left({ }_{1}^{3} \mathrm{H} \text { or } \mathrm{T}\right)\)

14. Applications of isotopes:

• An isotope of Uranium (U-235) is used as a fuel in nuclear reactors.
• An isotope of cobalt (C-60) is used in treatment of cancer by radiation therapy.
• An isotope of iodine is used in the treatment of goitre.
• Ages of old wooden articles are determined by observing the radioactivity of C-14 isotope of carbon.

15. Isobars:
Atoms of different elements with different atomic numbers which have the same mass number are known as isobars.

For example: Two elements – calcium, atomic number 20, and argon, atomic number 18 are isobars. The number of electrons in these atoms is different, but the mass number of both of these elements is 40.

Class 9 Science Chapter 4 Notes Important Terms

Cathode rays: It consist of negatively charged particles (electrons) emitted by passing electricity through gases at low pressure.

Anode rays: These rays are produced along with cathode rays and move towards cathode. They consist of positively charged ions.

Electrons: Electrons are fundamental particles carrying a unit negative charge and are a common constituent of all atoms.

Protons: (This positively charged particle was characterised in 1919). The fundamental particle which carries one unit of positive charge and has a mass nearly equal to that of an H-atom. Mass of proton = 1.6726 x 10^-24 g.

Neutron: The fundamental particle, which has a mass nearly equal to that of an H atom but has no charge.
Mass of neutron = 1.6749 x 10^-24 g.

Valency: It is the capacity of atoms of a given element to combine with, or replace atoms of hydrogen. In HCl gas, valency of chlorine is 1.

Nucleons: Protons and neutrons together are known as nucleons.

Isobars: Atoms having the same mass number but different atomic numbers.
For example, K – 40 and Ar – 40.

Isotopes: Atoms with identical atomic number but different mass numbers.
For example,\({ }_{1}^{1} \mathrm{H},{ }_{1}^{2} \mathrm{H} \text { and }{ }_{1}^{3} \mathrm{H}\)

On this page, you will find Chemical Reactions and Equations Class 10 Notes Science Chapter 1 Pdf free download. CBSE NCERT Class 10 Science Notes Chapter 1 Chemical Reactions and Equations will seemingly help them to revise the important concepts in less time.

CBSE Class 10 Science Chapter 1 Notes Chemical Reactions and Equations

Chemical Reactions and Equations Class 10 Notes Understanding the Lesson

1. Chemical reaction: The reaction in which the original state of the particles changes and it cannot be reversed by simple physical means, is known as a chemical reaction.
Examples: fermentation of grapes, burning of wood, etc. Burning of wood produces charcoal and we cannot get back wood from charcoal on reversing the conditions.

• Chemical reaction is accompanied by change in state, colour, evolution of gas or change in temperature. The chemical reaction is represented as
  Reactants → Products
• Example of a chemical reaction is burning of magnesium ribbon with a dazzling white flame to form a white powder (magnesium oxide).
  2Mg + O₂ → 2MgO

2. Chemical equation: Representation of a chemical reaction in terms of chemical symbols and formulae of the reactants and products is known as chemical equation. A chemical equation represents the reactants, products and their physical states symbolically.
For example,
Magnesium + Oxygen → Magnesium oxide
2Mg(s) + O₂(g) → 2MgO(s)
The substances that undergo chemical change in the reaction, i.e., magnesium and oxygen, are the reactants. The new substance, magnesium oxide, formed during the reaction is the product.

Writing a chemical reaction in terms of chemical equation: A chemical equation represents a chemical reaction. While writing a chemical equation the reactants are written on the left hand side of the equation while products on the right hand side.
Examples:

3. Balanced chemical equation: The chemical equation in which the number of atoms of different elements is same on both sides of the arrow is called a balanced chemical equation.
This is in accordance to the law of conservation of mass.
Let us try to balance the following chemical equation:
Fe + H₂O → Fe₃O₄ + H₂
Number of atoms of different elements present in the unbalanced equation

Element	Number of atoms in reactants (LHS)	Number of atoms in products (RHS)
Fe	1	3
H	2	2
O	1	4

Now select the element which has the maximum number of atoms Fe304. There are four oxygen atoms on the RHS and only one on the LHS.

To balance the oxygen atoms

Atoms of oxygen	In reactants	In products
(i) Initial	1 (in H2O)	4 (in Fe3O4)
(ii) To balance	1 x 4	4

So, multiplying H₂O molecules by four, we get
Fe + 4H₂O → Fe₃O₄ + H₂

To balance H atoms, make the number of molecules of hydrogen as four on the RHS.
Fe + 4H₂O → Fe₃O₄ + 4H₂

To equalise Fe, we multiply Fe atoms by three on the LHS.
Hence,
3Fe + 4H₂O → Fe₃O₄ + 4H₂ (Balanced equation)

To make chemical equation more informative gaseous, liquid, aqueous and solid states of reactants and products are represented by the notations (g), (l), (aq) and (s) respectively.
Hence,  3Fe(s) + 4H₂O(g) → Fe₃O₄(s) + 4H₂(g)

4.Types of chemical reactions
(a) Combination reaction: The reactions in which two or more substances combine to form a new substance is called combination reaction.
For example,

• 2Mg(s) + O₂ (fe)→ 2MgO(s)
• CaO(s) + H₂O(l) → Ca(OH)₂(aq)

(b) Decomposition reaction: The reaction in which a single compound breaks up into two or more simpler substances is called decomposition reaction. For example,

2Pb(NO₃)₂(s) → 2PbO(s) + 4NO₂(g)+ O₂(g)

The decomposition of a substance by passing electric current through it is known as electrolysis.

The decomposition of a substance on heating is known as thermal decomposition.

The decomposition of a substance by absorbing light energy is called photochemical decomposition.
For example,

The above two reactions are used in black and white photography.

Decomposition reactions are opposite of combination reactions.

(c) Displacement reaction: The chemical reaction in which a more reactive element displaces a less reactive element from its salt solution is known as displacement reaction. For example,

• Zn(s) + CuSO₄(aq)→  ZnSO₄(aq) + Cu(s)
• Cu(s) + 2AgNO₃(aq) → Cu(NO₃)₂ (aq) + 2Ag(s)

(d) Double displacement reaction: In this reaction two different atoms or group of atoms are mutually exchanged.

A white, insoluble substance, i.e., BaS04 is formed which is called precipitate.
Precipitation Reaction-Any reaction that produces a precipitate is called a precipitation reaction.

(e) Oxidation: Oxidation is the gain of oxygen or loss of hydrogen.

(f) Reduction: Reduction is the loss of oxygen or gain of hydrogen.

Redox reaction: The reaction in which one reactant gets oxidised while other gets reduced.

Exothermic reactions: Reaction in which heat is released along with the formation of products.
For example, \(\mathrm{CH}_{4}(g)+2 \mathrm{O}_{2}(g) \longrightarrow \mathrm{CO}_{2}(\mathrm{g})+2 \mathrm{H}_{2} \mathrm{O}(g)\)
Respiration and decomposition of vegetable matter into compost are exothermic reactions.

Endothermic reactions: The reactions which require energy in form of heat, light or electricity are called endothermic reactions.
\(2 \mathrm{Ba}(\mathrm{OH})_{2}+2 \mathrm{NH}_{4} \mathrm{Cl} \longrightarrow \text { Heat } \mathrm{2BaCl}_{2}+2 \mathrm{NH}_{4} \mathrm{OH}\)

5. Corrosion: The process of slow deterioration of some metals like iron, copper and silver into their compounds due to their reaction with oxygen, water, acids, gases, etc. present in the atmosphere is called corrosion.
Rusting The process in which iron reacts with oxygen and moisture present in the air to form a reddish brown coating called rust on its surface.

6. Rancidity: The taste and odour of food materials containing fat and oil changes when they are left exposed to air for a long time. This is called rancidity. It is caused due to oxidation of fat and oil present in food material. It can be prevented by using various methods such as by adding antioxidants to the food materials, storing food in air tight containers and by flushing out air with nitrogen.

Class 10 Science Chapter 1 Notes Important Terms

Chemical reaction is a process in which old bond breaks up and new bonds are formed.

Chemical equation is the representation of a chemical reaction in terms of chemical symbols and formulae.

Combination reaction is a reaction in which two or more substances combine to form a new substance.

Decomposition reaction is a reaction in which a single compound breaks up into two or more simpler substances.

Displacement reaction is a reaction in which a more reactive element displaces a less reactive element from its salt solution.

Redox reaction is the reaction in which oxidation and reduction takes place simultaneously.

On this page, you will find NCERT Class 9 History Chapter 6 Notes Pdf free download. CBSE Class 9 Social Science Notes History Chapter 6 SST Peasants and Farmers will seemingly, help them to revise the important concepts in less time.

Peasants and Farmers Class 9 Notes Social Science History Chapter 6

CBSE Class 9 History Chapter 6 Notes Understanding the Lesson

1. This lesson deals with the small cottages in England, the wheat farmers of the USA, and the opium producers of Bengal and what happened to them with the coming to modern agriculture.

2. It is England where the agriculture revolution first occurred. Over the late eighteenth and early nineteenth centuries the English countryside changed dramatically.

3. Before this time in large parts of England the countryside was open where peasants cultivated, pastured their cows and grazed their sheep. For the poor, the common land was essential for survival.

4. But their life change miserably when common land began to be enclosed. Rich farmers drove them out and prevented them from entering the enclosed fields.

5. The early enclosures were usually created by individual landlords. They were not supported by the state or the church. After the mid-eighteenth century, however the enclosure movement swept through the countryside, changing the English landscape forever. The British Parliament legalized these enclosures.

6. Unlike the early enclosures that promoted sheep farming, the land being enclosed in the late eighteenth century was for grain production to feed the growing population.

7. Landlords were encouraged to enclose lands and enlarge the area under grain cultivation. Farmers at this time continued to use the simple innovations in agriculture that had become common by the early eighteenth century.

8. Enclosures allowed the richer landowners to expand the land under their control and produce more for the market. But it worsened the condition of the poor. They could no longer collect their firewood from the forests, or graze their cattle on the commons.

9. In places where enclosures happened on an extensive scale—the poor were displaced from the land. They found their customary rights gradually disappearing. Deprived of their rights and driven off the land, they wandered in search of work.

10. The introduction of threshing machines increased the miseries of the poor. The rich farmers bought the new threshing machines that had come into the market. This reduced their dependence on laborers. As a result, their income became instable, their jobs insecure, their livelihood precarious. For them the threshing machines had become a sigh of bad times.

11. At the time that common fields were being enclosed in England at the end of the eighteenth century, settled agriculture had not developed on any extensive scale in the USA. Forests covered over 800 millions acres and grasslands 600 million acres.

12. By the early nineteenth century, this landscape had transformed radically. White Americans had moved westward and established control upto the west coast, displacing local tribes and carving out the entire landscape into different agricultural belts.

13. The story of agrarian expansion is closely connected to the westward movement of the white settlers who took over the land. After the American War of Independence from 1775 to 1783 and the formation of the United States of America, the white Americans began to move westward and turn forests into cultivated fields.

14. From the late nineteenth century, wheat production expanded in the USA dramatically. By the early twentieth century about 45 million acres of land in the USA was under wheat. The area soon expanded to 74 million acres. This dramatic expansion was made possible by new technological innovations such as mechanical reapers, drills, tractors, etc.

15. For the poorer farmers, machines brought miseries. They became jobless because mechanization had reduced the need for labour. The boom of the late nineteenth and early twentieth centuries came to an end by the mid-1920s. There was large surplus wheat which lowered down its prices.

16. The expansion of wheat agriculture in the Great Plains created ecological problems too because zealous farmers had recklessly uprooted all vegetation, and tractors had turned the soil over, and broken the sod into dust. In the early twentieth century, the whole region had become a dust bowl.

17. In the colonial period, rural India produced a range of crops for the world market. In the early nineteenth century, indigo and opium were two of the major commercial crops. By the end of the century, peasants were producing sugar cane, cotton, jute, wheat and several other crops for export.

18. The history of opium production in India was linked up with the story of British trade with China. In the late eighteenth century, the English East India Company was buying tea and silk from China for sale in England. As tea became a popular English drink, the trade became very important.

19. But there was a problem. England at this time produced nothing that could be easily sold in China. Opium, they thought, could be sold in China so they persuaded Indian farmers to grow this commodity.

20. They introduced system of advances to trap the poor farmers of Bengal and Bihar. When offered a loan, they readily accepted it, hoping to meet their immediate needs and pay back the loan at a later stage. But the loan tied the peasants to the headmen and through him to the government.

21. By taking the loan, the cultivator was forced to grow opium on a specified area of land and handover the produce to the agents once the crop had been harvested. Here, it is worth mentioning that the prices given to the peasants were very low.

Peasants and Farmers Class 9 CBSE Notes Important Terms

Bushel: A measure of capacity.

Shillings: An English currency. (20 shillings = £ 1)

Commons: Land or resources belonging to or affecting the whole of a community.

Sod: Pieces of earth with grass.

Maund: A measure of weight. (1 maund = 40 seers. 1 seer is a little under a kg))

Opium: The dried latex obtained from the opium poppy.

Scythe: A machine used for mowing grass.

Agrarian: Relating to cultivated land or the cultivation of land.

Enclosure: An area that is surrounded by a barrier.

On this page, you will find NCERT Class 9 History Chapter 5 Notes Pdf free download. CBSE Class 9 Social Science Notes History Chapter 5 SST Pastoralists in the Modern World will seemingly, help them to revise the important concepts in less time.

Pastoralists in the Modern World Class 9 Notes Social Science History Chapter 5

CBSE Class 9 History Chapter 5 Notes Understanding the Lesson

1. Pastoralism has been important in societies like India and Africa. Here we will read about the way colonialism impacted their lives, and how they have coped with the pressures of modern society. Pastoralism in India-Pastoralists are found in mountains, plateaus, plains and deserts of India. In the mountains of Jammu and Kashmir are found the Gujjar Bakarwals. They are great herders of goat and sheep.

2. The Gaddi shepherds are found in Himachal Pradesh. Further to the east, in Garhwal and Kumaon, the Gujjar cattle herders can be seen.

3. These pastoral communities moved annually between their summer and winter grazing grounds. They had to adjust to seasonal changes and make effective use of available pastures in different places. When the pasture was exhausted or unusable in one place they moved their herds and flock to new areas.

4. Dhangars were an important pastoral community of Maharashtra. They stayed in the central plateau of Maharashtra during the monsoon, grew bajra and moved west by October. After a march of about one month they reached the Konkan where they lived till the onset of monsoon. Afterwards, they left the Konkan and the coastal areas with their flocks and returned to the settlements on the dry plateau.

5. In Karnataka and Andhra Pradesh, the dry central plateau was inhabited by cattle, goat and sheepherders. The Gollas herded cattle. The Kurumas and Kurubas reared sheep and goats and sold woven blankets.

6. Banjaras were well-known group of graziers. They were to be found in the villages of Uttar Pradesh, Punjab, Rajasthan, Madhya Pradesh and Maharashtra.

7. In the deserts of Rajasthan lived the Raikas. They combined cultivation with pastoralism. One group of Raikas-known as the Maru (desert) Raikas-herded camels and another group reared sheep and goat.

8. The life of pastoralists changed dramatically during the colonial rule. Their grazing grounds shrank, their movements were regulated, and the revenue they had to pay increased.

9. The colonial government enacted Forest Acts which prevented pastoralists from entering many forests that had earlier provided valuable forage for their cattle.

10. The British officials were suspicious of nomadic people. Since they kept on moving from one place to another, they were considered to be criminal. In 1871, the colonial government in India passed the Criminal Tribes Act to check their movement.

11. As pasturelands were turned into cultivated fields, the existing animal stock had to feed on whatever grazing land remained. This led to continuous intensive grazing of these pastures. As a result of this the quality of pastures declined. This in turn created a further shortage of forage for animals and the deterioration of animal stock.

12. Some pastoralists reduced the number of cattle in their herds, because there was dearth of enough pastures. Others discovered new pastures when movement to old grazing grounds became difficult. And thus, pastoralists continue to survive. In many regions their numbers have also expanded over recent decades.

13. Pastoralism in Africa-Over half the world’s pastoral population lives in Africa. Even today, over 22 million Africans depend on some form of pastoral activity for their livelihood. They include communities like Bedouins, Berbers, Maasai, Somali, Boran and Turkana.

14. Like pastoralists in India, the lives of African pastoralists have changed dramatically over the colonial and post-colonial periods. We can take example of one pastoral community-the Maasai-whose life changed when new laws and regulations were imposed on them by the colonial government.

15. The Maasai cattle herders live primarily in east Africa in Kenya and Tanzania. Before colonial times, Maasai land stretched over a vast area from north Kenya to the steppes of northern Tanzania. In the late nineteenth century, their best grazing lands were gradually taken over for white settlement and they were pushed into a small area in south Kenya and north Tanzania.

16. From the late nineteenth century, the British colonial government in east Africa also encouraged local peasant communities to expand cultivation. As a result, pasturelands were turned into cultivated fields. Large areas of grazing land were also turned into game reserves like the Maasai Mara and Samburu National Park in Kenya and Serengeti Park in Tanzania.

17. The loss of the finest grazing lands and water resources created pressure on the small area of land that the Maasai were confined within. Continuous grazing within a small area deteriorated the quality of pastures.

18. Like the Maasai, other pastoral groups were also forced to live within the confines of special reserves. The boundaries of these reserves became the limits within which they could now move.

19. The new territorial boundaries and restrictions imposed on them suddenly changed the loves of pastoralists. This adversely affected their pastoral and trading activities.

20. Pastoral communities in different parts of the world are affected in a variety of different ways by changes in the modem world. New laws and new borders affect the patterns of their movement. Yet, they do adapt to new times. They change the paths of their annual movement and reduce their cattle number but at the same time also demand a right in the management of forests and water resources.

Pastoralists in the Modern World Class 9 CBSE Notes Important Terms

Nomads: People who do not live in one place but move from one area to another to earn their living.

Pastoralism: The branch of agriculture concerned with the raising of livestock. It is animal | husbandry: the care, tending and use of animals such as camels, goats, cattle, etc.

Kafila: When several households come together for a journey, it is known as

Bhabar: A dry forested area below the foothills of Garhwal and Kumaun.

Bugyal: Vast meadows in the high mountains.

Kharif: The autumn crop, usually harvested between September and October.

Rabi: The spring crop, usually harvested after March.

Stubble: Lower ends of grain stalks left in the ground after harvesting.

Customary rights: Rights that people are used to by custom and tradition.

Livestock: Cattle, goats and sheep.

Drought: A period of below-average precipitation in a given region, resulting in prolonged shortages in its water supply.

Forage: Plant material (mainly plant leaves and stems) eaten by grazing livestock.

On this page, you will find NCERT Class 9 History Chapter 4 Notes Pdf free download. CBSE Class 9 Social Science Notes History Chapter 4 SST Forest Society and Colonialism will seemingly, help them to revise the important concepts in less time.

Forest Society and Colonialism Class 9 Notes Social Science History Chapter 4

CBSE Class 9 History Chapter 4 Notes Understanding the Lesson

1. Forests treasure valuable resources. They provide us many things, such as paper, gum, honey, rubber, fruits, flowers and many other things.

2. Forest area is fast disappearing due to various reasons. The process of deforestation began many centuries ago; but under colonial rule it became more systematic and extensive.

3. In the colonial period, cultivation expanded rapidly for a variety of reasons. The British thought that forests were unproductive. They were considered to be wilderness that had to be brought under cultivation so that the land could yield agricultural products and revenue. This led to the clearance of forests.

4. By the 1830s, trees were felled on a massive scale and vast quantities of timber were exported from India to England.

5. The spread of railways from the 1850s also led to deforestation. Large areas of natural forests were also cleared to make way for tea, coffee and rubber plantations to meet Europe’s growing need for these commodities.

6. In order to manage the forests the British made Dietrich Brandis, a German expert, the first Inspector General of Forests in India. Brandis thought that felling of trees and grazing should be restricted in order to preserve forests for timber production. Hence, rules about the use of forest resources were made. Anybody who cut trees without permission was punished.

7. Brandis introduced ‘scientific forestry’ in which natural forests which had lots of different types of trees were cut down. In their place, one type of tree was planted in straight rows.

8. In 1865, the Forest Act was enacted. It was amended twice, once in 1878 and then in 1927. The 1878 Act divided forests into three categories-reserved, protected and village forests. The best forests were called ‘reserved forests’. Villagers could not take anything from these forests.

9. The Forest Act meant severe hardship for villagers across the country. After the Act, all their everyday practices such as grazing cattle, collecting fruits and roots, etc., became illegal.

10. The British government also banned shifting cultivation. As a result, many communities were forcibly displaced from their homes in the forests. The new forest laws also deprived the forest dwellers of their customary rights to hunt. Those who were caught hunting were now punished for poaching.

11. Some people, however, benefited from the new opportunities that had opened up in trade. Many communities started trading in forest products such as hides, horns silk cocoons, bamboo, spices, fibres, grasses, gums and resins, etc.

12. New opportunities of work did not always mean improved well-being for the people. In Assam, both men and women from forest communities like Santhals and Oraons from Jharkhand, and Gonds from Chhattisgarh were recruited to work on tea plantations. Their wages were low and conditions of work were very bad.

13. In many parts of India, and across the world, forest communities rebelled against the changes that were being imposed on them. The first rebellion took place in Bastar district in Madhya Pradesh in 1910 which was suppressed by the British troops.

14. The colonial power in Indonesia were the Dutch and there were many similarities in the laws for forest control in Indonesia and India. Java in Indonesia is where the Dutch started forest management. Like the British, they wanted timber from Java to build ships.

15. The Dutch enacted forest laws in Java, restricting villagers access to forests. They were punished for grazing cattle in young stands, transporting wood without a permit, or travelling on forest roads with horse carts or cattle.

16. Around 1890, Surontiko Samin of Randublating village, a teak forest village, began questioning state ownership of the forest. He argued that the state could not own wind, water, earth and wood. Soon a widespread movement developed.

17. War and deforestation are closely related. The two world wars had a major impact on forests. In India, the forest department cut trees freely to meet British war needs. In Java, just before the Japanese occupied the region, the Dutch followed ‘a scorched earth’ policy, destroying sawmills, and burning huge piles of giant teak logs so that they would not fall into Japanese hands.

18. Conservation of forests has now become and important goal. The government has recognized that in order to meet this goal, the people who live near the forests must be involved.

Forest Society and Colonialism Class 9 CBSE Notes Important Terms

Deforestation: The disappearance of forests.

Sleepers: Wooden planks laid across railway tracks; they hold the tracks in position.

Plantation: Planting of one type of trees in straight rows.

Scientific forestry: A system of cutting trees controlled by the forest department in which old trees are cut and new ones planted.

Poaching: The illegal practice of trespassing on another’s property to hunt or steal game without the landowner’s permission.

Pargana: Cluster of villages.

Notes of History Class 9 Chapter 4 Time Period

1850s: the spread of railways started from this period.

1860s: The railway network expanded rapidly from this period.

1864: The Indian Forest Service was set up.

1865: The Forest Act was enacted.

1878: The Forest Act was amended.

1910: Rebellion took place in the Kingdom of Bastar.

1927: The Forest Act was amended.

On this page, you will find NCERT Class 9 History Chapter 3 Notes Pdf free download. CBSE Class 9 Social Science Notes History Chapter 3 SST Nazism and the Rise of Hitler will seemingly, help them to revise the important concepts in less time.

Nazism and the Rise of Hitler Class 9 Notes Social Science History Chapter 3

CBSE Class 9 History Chapter 3 Notes Understanding the Lesson

1. Germany was a powerful empire in the early twentieth century. It fought the First World War (1914-1918) alongside the Austrian empire and against the Allies.

2. Germany was defeated in 1918 and the emperor was abdicated. This gave an opportunity to parliamentary parties to recast German polity. A National Assembly met at Weimar and established a democratic constitution with a federal structure.

3. German people did not welcome the new Weimar Republic because they held it responsible for the defeat of Germany in the war and the disgrace at Versailles.

4. Germany faced deep economic crisis in 1923. It had fought the war largely on loans and had to pay war reparations in gold. This depleted gold reserves at a time resources were scarce.

5. The German economy was further hit by the Great Economic Depression. By 1932, industrial production was reduced to 40 percent of the 1929 level. Workers lost their jobs. The economic crisis created deep anxiety and fears in people. Since the Weimar Republic failed to manage this crisis; people lost confidence in the democratic parliamentary system.

6. All this formed the background of Hitler’s rise to power. The German defeat horrified Hitler and the Versailles Treaty made him furious. In 1919, he joined the German Worker’s Party. He subsequently took over the organization and renamed it the National Socialist German Worker’s Party which later came to be known as the Nazi Party.

7. Nazism became a mass movement during the Great Depression. In a situation when workers lost jobs and the middle classes were threatened with destitution, Nazi propaganda stirred hopes in them. In 1928, the Nazi Party was not very successful but by 1932, it had become the largest party. Hitler impressed the German people with his powerful speeches. He promised them to build a strong nation, undo the injustice of the Versailles Treaty and restore their dignity.

8. On 30 January 1933, Hitler was offered the Chancellorship of Germany. Having acquired power, Hilter set out to dismantle the structures of democratic rule. Civic rights like freedom of speech, press and assembly were suspended. The Communists were sent to the newly established concentration camps.

9. The famous Enabling Act, passed on 3 March 1933, established dictatorship in Germany. Hilter became the most powerful man in the country. He sidelined Parliament and rule by decree. He also banned all political parties and trade unions.

10. Special surveillance and security forces were created to control and order society in ways that the Nazis wanted. People could now be detained in Gestapo (secrete state police) torture chambers, rounded up and sent to concentration camps.

11. Hitler got quick success in his foreign policy. He integrated Austria and Germany in 1938 under the slogan, One people, One empire and One leader.

12. In September 1939, Germany invaded Poland. This started a war with France and England. In September 1940, a Tripartite Pact was signed between Germany, Italy and Japan which strengthened Hitler’s claim to international power.

13. Hitler created an exclusive racial community of pure German by eliminating all those who were seen as ‘undesirable’ in extended empire. Nazis wanted only a society of pure and healthy Nordic Aryan’s. Only they were seen as worthy of prospering and multiplying against all who were classed; as ‘undesirables’.

14. Jews, Gypsies and blacks living in Nazi Germany were widely persecuted. Even Russians and Poles were considered subhuman. However, Jews remained the worst sufferers. They were terrorized, pauperized and segregated.

15. Hitler was fanatically interested in the youth of the country. He felt that a strong Nazi society could be established only by teaching children Nazi ideology. So, all schools were ‘cleansed’ and ‘purified’. Jew teachers and children were thrown out of schools.

16. School textbooks were rewritten, racial science was introduced to justify Nazi ideas of race. Children were taught to be loyal and submissive, hate Jews, and worship Hitler.

17. Youth organizations were made responsible for educating German youth in ‘the spirit of National Socialism’. Ten-year-olds had to enter Jungvolk and at 14 all boys had to join the Nazi youth organization e. Hilter youth where they learnt to worship war, glorify aggression and violence, and condemn democracy.

18. In Nazi Germany, all mothers were not treated equally. Women who bore racially undesirable children were punished and those who produced racially desirable children were awarded.

19. The art of propaganda that Nazis used was peculiar. They never used the words ‘kill’ or ‘murder’ in their official communications. Mass killings were termed special treatment, final solution (for the Jews), euthanasia (for the disabled), selection and ‘Evacuation’ meant deporting people to gas chambers.

Nazism and the Rise of Hitler Class 9 CBSE Notes Important Terms

Allies: The Allied Powers were initially led by the UK and France. In 1941 they were joined by the USSR and USA. They fought against the Axis Powers, namely Germany, Italy and Japan.

Genocidal: Killing on large scale leading to destruction of large sections of people.

Deplete: Reduce, empty out.

Reparation: Make up for a wrong done.

Wall Street Exchange: The name of the world’s biggest stock exchange located in the USA.

Hyperinflation: A situation when prices rise phenomenally high.

Proletarianization: To become impoverished to the level of working classes.

Propaganda: Specific type of message directly aimed at influencing the opinion of people through the use of posters, films, speeches, etc.

Concentration camp: A camp where people were isolated and detained without due process of law. Typically, it was surrounded by electrified barbed wire fences.

Nordic German Aryans: One branch of those classified as Aryans. They lived in north European countries and had German or related origin.

Gypsy: The groups that were classified as ‘gypsy’ had their own community identity. Sinti and Roma were too such communities. Many of them traced their origin to India.

Pauperised: Reduce to absolute poverty.

Persecution: Systematic, organized punishment of those belonging to a group or religion.

Usurers: Moneylenders charging excessive interest, often used as a term of abuse.

Synagogues: Place of worship for people of Jewish faith.

Jungvolk: Nazi youth groups for children below 14 years of age.

Holocaust: It was a genocide in which Hitler’s Nazi Germany and its collaborators killed about six million Jews.

Notes of History Class 9 Chapter 3 Time Period

1914: The First World War broke out.

1917: Entry of the USA in the First World War.

1918: The First World War ended.

1919: Treaty of Versailles.

1923: Economic crisis in Germany.

1929: The Great Economic Depression started.

1932: The Nazi Party became the largest party in the German Parliament.

1933: Hilter was made Chancellor of Germany.

1939: Germany invaded Poland, Second World War began.

1940: Hitler was at the height of his power.

1941: The USA joined Second World War.

1945: Allied victory in Europe, Hitler was defeated.

On this page, you will find NCERT Class 9 History Chapter 2 Notes Pdf free download. CBSE Class 9 Social Science Notes History Chapter 2 SST Socialism in Europe and the Russian Revolution will seemingly, help them to revise the important concepts in less time.

Socialism in Europe and the Russian Revolution Class 9 Notes Social Science History Chapter 2

CBSE Class 9 History Chapter 2 Notes Understanding the Lesson

1. The powerful ideas of freedom and equality circulated in Europe after the French Revolution. In many parts of the world including Europe and Asia, new ideas about individual rights and who controlled social power began to be discussed.

2. Not everyone in Europe wanted a complete transformation of society. Responses varied from those who accepted that some change was necessary but wished for a gradual shift, to those who wanted to reconstruct society radically. Some were conservatives, others were liberals or radicals. Conservatives were opposed to radicals and liberals. After the French Revolution, however, even conservatives had opened their minds to the need for change.

3. Liberals and radicals opposed to the privileges the old aristocracy had by birth because they firmly believed in aristocracy had by birth because they firmly believed in the value of individual effort, labour and enterprise. So, many working men and women rallied around liberal and radical groups and parties in the early nineteenth century.

4. By the mid-nineteenth century in Europe, socialism attracted widespread attention. Socialist were against private property, and saw it as the root of all social evils of the time. They wanted that attention should be part to collective social interest.

5. Karl Marx was against capitalism. He believed that to free themselves from capitalist exploitation, workers had to construct a radically socialist society where all property was socially controlled. This would be a communist society.

6. Socialists took over the government in Russia in 1917 by a eliminating monarchy there. But this came about after a long struggle.

7. In 1914, Tsar Nicholas II ruled Russia and its empire. At that time, the vast majority of Russia’s people were agriculturists. Industries were few and were controlled by industrialists.

8. Russia was an autocracy. Unlike other European rulers, even at the beginning of the twentieth century, the Tsar was not subject to parliament. Liberals in Russia campaigned to end this system. The year 1904 was bad for Russian workers. Prices of essential goods rose so quickly that real wages declined by 20 percent. Hence, the workers in St. Petersburg went on strike demanding an increase in wages.

9. When the procession of workers reached the Winter Palace it was attacked by the police and the Cossacks. Hundreds of workers were killed and many were wounded. The incident, known as Bloody Sunday, started a series of events that came to be known as the 1905 Revolution.

10. During the 1905 Revolution, the Tsar allowed the creation of an elected consultative Parliament or Duma. But he dismissed the first Duma within 75 days and re-elected second Duma within three months. He did not want any reduction in his power. He changed the voting laws and packed the third Duma with conservative politicians.

11. In 1914, the first world war was broke out. In Russia, the war was initially popular and people rallied around the Tsar. But soon the number of his supporters went down, because he did not pay any heed to the soldier’s welfare.

12. The Russians Revolution of 1917 revolves around two primary events—the February Revolution and the October Revolution. The February Revolution brought down the monarchy in Russia through violent demonstrations and riots on the street of Petrograd.

13. But the February Revolution failed to express the wishes of the majority of the Russian population, as the event was primarily limited to the city of Petrograd.

14. However, most of those who took power after the February Revolution, in the Provisional Government that replaced the Tsar, and in the Petrograd Soviet generally favoured rule that was at least partially democratic.

15. The October Revolution, also called the Bolshevik Revolution, overturned the interim Provisional Government and established the Soviet Union.

16. After October, the Bolsheviks realised that they could not maintain power in an election-based system without sharing power with other parties and compromising their principles. As a result, they formally abandoned the democratic process in January 1918 and declared themselves the representatives of a dictatorship of the proletariat. In response, the Russian civil war broke out which lasted till 1920.

17. During the civil war, the Bolsheviks kept industries and banks nationalized. They permitted the peasants to cultivate the land that had been socialized. They also introduced centralized planning which led to economic growth.

18. The Bolsheviks encouraged colonial peoples to follow their experiment. Many non-Russians participated in the conference of the peoples of the East and the Bolshevik founded Comintern. By the time of the outbreak of the Second World War, the USSR had given socialism a global face but afterwards it began losing its popularity.

Socialism in Europe and the Russian Revolution Class 9 CBSE Notes Important Terms

Conservative: A person who favours free enterprise, private ownership, and holds traditional values.

Radical: A person who advocates thorough or complete political or social reform.

Liberal: A person who is open to new ideas.

Suffragette movement: A movement to give women the right to vote.

Autocracy: A system of government by one person with absolute power.

Jadidists: Muslim reformers within the Russian Empire.

Read wage: Reflects the quantities of goods which the wages will actually buy.

Deported: Forcibly removed from one’s own country.

Exiled: Forced to live away from one’s own country.

Collectivization: Consolidation of individual landholdings and labor into collective farms.

Socialism: A political and economic theory of social organization which advocates that the means of production distribution and exchange should be owned or regulated by the community as a whole.

Kulaks: The name for well-to-do peasants in Russia.

Notes of History Class 9 Chapter 2 Time Period

1850s-1880s: Debates over socialism in Russia.

1898: Formation of the Russian Social Democratic Workers Party.

1905: The Bloody Sunday and the Revolution of 1905.

1917: 2nd March- Abdication of the Tsar.

24th October- Bolshevik uprising in Petrograd.

1918-20: The Civil war in Russia.

1919: Formation of Comintern.

1929: Beginning of Collectivisation.

On this page, you will find NCERT Class 9 History Chapter 1 Notes Pdf free download. CBSE Class 9 Social Science Notes History Chapter 1 SST The French Revolution will seemingly, help them to revise the important concepts in less time.

The French Revolution Class 9 Notes Social Science History Chapter 1

CBSE Class 9 History Chapter 1 Notes Understanding the Lesson

1. In 1774, Louis XVI of the Bourbon family of kings ascended the throne of France. Upon his accession the new king found an empty treasury. So the state was forced to increase taxes.

2. French society in the eighteenth century was divided into three estates, but only the members of the third estate had to pay taxes. The third estate was comprised of big businessmen, merchants, court officials, peasants and artisans. The members of the first two estates, that is, the clergy and the nobility, enjoyed certain privileges by birth.

3. The phenomenal increase in the population of France in 1789 led to a rapid increase in the demand for food grains. As a result the price of bread rose rapidly. It became difficult for the poor to keep pace with the rise in prices. The gap between the poor and the rich widened.

4. In the eighteenth century there emerged new social groups, termed the middle class. The people belonging to this class were educated and believed that no group in society should be privileged by birth. Rather, a person’s social position must depend on this merit.

5. Philosophers such as John Locke, Jean Jacques Rousseau and Montesquieu put forward the ideas of freedom and equal laws and opportunities for all. These philosophers refuted the doctrine of the divine and absolute right of the monarch.

6. At a time when general public was facing hard times, the news that Louis XVI planned to impose further taxes generated anger among them. They protested against the system of privileges. But as Louis XVI had to increase taxes, he called together an assembly of the Estates-General on 5 May 1789, to pass proposals for new taxes.

7. Voting in the Estates-General in the past had been conducted according to the principle that each estate had one vote. This time too Louis XVI was determined to continue the same practice. But the members of the third estate demanded that voting now be conducted by the assembly as a whole, where each member would have one vote. However, the king rejected their proposal which compelled them to walkout.

8. Meanwhile, the representatives of the third estate assembled in the grounds of Versailles on 20 June and declared themselves a National Assembly. They had drafted a constitution for France that would limit the powers of the monarch.

9. In the meantime the condition of the common mass in France worsened because of the bad harvest. Unaware of his subjects problem the king ordered troops to move into Paris on 4 July, the agitated crowed stormed and destroyed Bastille.

10. Louis XVI, could not suppress his revolting subjects and finally accorded recognition to the National Assembly and accepted the principle that his powers would from now on be checked by a constitution.

11. On the night of 4 August 1789, the Assembly passed a decree abolishing the feudal system of obligations and taxes. Members of the clergy too were forced to give up their privileges.

12. The National Assembly completed the draft of the constitution in 1791. Powers were now separated and assigned to different institutions-the legislature, executive and judiciary.

13. The constitution began with a Declaration of the Rights of Man and Citizen. Rights such as the right to life, freedom of speech, freedom of opinion, equality before law, were established as natural rights.

14. But one wrong step of Louis XVI worsened the situation in France. Although he had signed the constitution, he entered into secret negotiations with the king of Prussia. In the meantime, the National Assembly declared war against Prussia and Austria. Thousands of volunteers joined the army. They saw this as a war of the people against kings and aristocracies all over Europe.

15. Large sections of population were in favour of the continuation of revolution, as the constitution of 1791 gave political rights only to the richer sections of society. Political clubs came into existence. They wanted to plan their own forms of action. The most successful of these clubs was that of the Jacobins.

16. The members of the Jacobin club belonged mainly to the less prosperous sections of society. Their leader was Maximilian Robespierre.

17. In the summer of 1792 the Jacobins planned an insurrection of a large number of Parisians who were angered by the short supplies and high prices of food. On the morning of August 10 they stormed the Palace of the Tuileries, killed the king’s guards and held the king himself as hostage. Later, the Assembly imprisoned the royal family.

18. Louis XVI and his queen were sentenced to death in 1793. Thus, monarchy was abolished and France was made a republic. Then started the Reign of Terror in France under the leadership of Robespierre. But it could last for long. In July 1794, Robespierre was arrested and then sentenced to death.

19. The fall of the Jacobin government allowed the wealthier middle classes to seize power. But political instability continued which paved the way for the rise of Napoleon Bonaparte who crowned himself Emperor of France in 1804. He was finally defeated at Waterloo in 1815.

20. The Ideas of liberty and democratic rights were the most important legacy of the French Revolution for the peoples of the world during the nineteenth and twentieth centuries.

The French Revolution Class 9 CBSE Notes Important Terms

Livre: Unit of currency in the France, discontinued in 1794.

Clergy: Group of persons invested with special functions in the church.

Tithe: A tax levied by the church, comprising on tenth of the agricultural produce.

Taille: Tax to be paid directly to the state.

Subsistence: An extreme situation where the basic means of livelihood are endangered.

Chateau: (PI. chateaux)-Castle or stately residence belonging to a king or a nobleman.

Manor: An estate consisting of the lord’s lands and his mansion.

Treason: Betrayal of one’s country or government.

Guillotine: A device consisting of two poles and a blade with which a person is beheaded.

Negroes: A term used for the indigenous people of Africa south of the Sahara.

Emancipation: The act of freeing.

Marseillaise: The national anthem of France.

Sans-culottes: Those without knee-breeches.

Notes of History Class 9 Chapter 1 Time Period

1774: Louis XVI became the king of France.

1789: The Bastille was stormed.

1791: A constitution was framed to limit the power of the king.

1792-93: France became a republic, the king was beheaded.

1804: Napoleon became the emperor of France.

1815: Napoleon was defeated at Waterloo.