Matter is the matter of all the matter .

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1. Matter Presented by Mrs. suneetha Luke m

2. What is Matter ? Anything which occupies space, has mass and can be perceived by our physical senses is called matter.

3. Characteristics of Matter

4. Material A substance from which something is made or can be made is called a material . Ex : wood, water, marble, etc. Kinds of Materials Homogeneous Materials Heterogeneous Materials

5. Kinetic Molecular Theory of Matter The main postulates of this theory are: All matter is composed of small particles called molecules or atoms . The particles are in a state of unending motion and a such have kinetic energy. With the supply of heat energy to matter, the kinetic energy of its particles increases. Reverse happens, if the matter is cooled.

6. Kinetic Molecular Theory of Matter The particles attract each other with a force. This force is called cohesive force, if the particles are of the same kind and adhesive force if the particles are of different kinds. The force of attraction between the particles decreases, if the distance between them increases and vice versa.

7. States of Matter and Their Properties SOLID A solid is that state of matter which has a definite shape and definite volume. Properties of solids They have definite shape and volume. They are generally rigid. They can have any number of free surfaces. Their density is generally high. They do not diffuse. The intermolecular spaces are very small and intermolecular forces are very large The dimensions of solids do not increase on large proportion on heating or cooling.

8. Explanation of a Solid on the Basis of Kinetic Model The definite shape and volume of solids can be explained on the basis of kinetic theory of matter. The molecules of the solids can just vibrate about their mean positions, but cannot migrate from one position to another. Examples of solids: All metals, wood, etc.

9. LIQUID A liquid is a state of matter which has definite mass and volume but no definite shape. Properties of Liquids Liquids have definite mass and volume but do not have a definite shape. The force of attraction between molecules of the liquids is less than the solids. Intermolecular space in liquids are larger than solids. Thus, they are slightly more compressible. They have only one free space. Their density is relatively less than the solids. Liquids expand far more than solids on heating and contract far more than solids on cooling. The particles of two different liquids can diffuse in one another, depending on the nature of the molecules of the liquids.

10. Explanation of a Liquid on the basis of Kinetic Model On the basis of the kinetic theory of matter we can say that kinetic energy of the molecules of a liquid is very large, and so is the distance between the molecules. Thus, the attractive force of the molecules is small as compared to solids. Therefore, the molecules of a liquid are free to move about within the liquid and hence, the liquid can easily take the shape of the containing vessel. Ex: Water, alcohol, benzene, etc .

11. GAS A gas is a state of matter, which has definite mass, but no definite shape and no definite volume . Properties of Gas A gas contained in a vessel has a definite mass. A gas can occupy the entire space of a given vessel. Intermolecular spaces are very large as compared to solids and liquids. They are highly compressible. Gases have no free surface and they diffuse in one another to form a homogeneous mixture. There are no intermolecular forces, they expand to a large extent when heated and contract to a large extent when cooled. The density of gases is extremely small as compared to solids and liquids .

12. Explanation of a Gas on the Basis of Kinetic Model The intermolecular distance between the molecules of a gas are very large with the result that the force of attraction between the molecules is negligible. The molecules have a very large kinetic energy. Thus, the molecules can move in any direction and hence can fill any space. Thus, the gases have no definite shape and no definite volume and are highly compressible. Ex: Oxygen, Nitrogen, hydrogen, etc.

13. Interparticle Space and Interparticle Attraction. Solids The interparticle spaces are very small. the interparticle attraction is very strong and there is no collision of particles.