Grouping on the basis of common properties

• Materials can be grouped on the basis of their properties.
• Different types of materials have different properties.
• We have to choose materials with the right properties for what we want to use it for.
• For example, a chalk made of wood or plastic would be of no use because it cannot be used to write on the blackboard.

Natural and Man Made Materials:

• Natural materials are those materials which occur in nature of their own and can be used or processed to make them more useful.

• E.g. wood, cereals, coal, silk, cotton, stone, water, wax, jute etc
• The materials which do not occur in nature but are made artificially by humans are called man-made materials.

• E.g., plastics, glass, nylon, soaps, detergents etc

Matter:

• Matter is anything that occupies space and has a definite mass.
• It includes all the materials found in universe.
• All substances are made up of matter.

States of Matter:

• Matter can exist in three states. These are:

1. solid state
2. liquid state
3. gaseous state

• Solid, liquid and gaseous state can be interchanged.

Different States of Matter:

Solids:

• Solid state has following characteristics:

1. In solids particles are very closely packed.
2. They have a definite shape and volume.
3. They cannot be compressed.

Sofa and ship are examples of solid state

Liquids:

• Liquid state has following characteristics:

1. In liquids, particles are not compactly packed, have a little space between them.
2. They have a definite volume but do not have definite shape.
3. They take the shape of the container they are poured in.
4. They can only be compressed to a small extent.

Water is an example of liquid state

Gases:

• Gaseous state has following characteristics:

1. In gaseous state particles are far from each other having large spaces between them.
2. They do not have a definite shape or volume.
3. They are highly compressible.

Air in basketball and balloon is an example of gaseous state

Interconversion of states:

Interconversion of states

• The process in which liquid state converts into gaseous state is called vapourization.
• The process in which gaseous state converts into solid state is called deposition.
• The process in which solid state converts into liquid state is called fusion.
• The process in which liquid state converts into solid state is called solidification.
• The process in which solid state converts into gas state is called sublimation.
• The process in which gaseous state converts into liquid state is called condensation.

Properties of Matter: