Synthetic materials.

Material created by man using natural materials is known as synthetic materials.

SOME SYNTHETIC MATERIALS:

Cement:

Discovered by English Mason, Joseph Aspdin, he named it Portland cement.

Limestone, clay and gypsum are some important raw material that is required in the manufacturing of the cement.

When cement is mixed with water and left for some time, it becomes a hard mass. This is known as setting of Cement, it is an exothermic process that’s why sprinkling of water is done for few days for a new construction.

Mortar is a mixture of cement, sand and water; it is used for plastering walls and binding bricks.

Concrete is a mixture of cement, sand, gravel and water. It is used for the construction of floors.

Structure having iron rods embedded in wet concrete is known as reinforced concrete.

Glass :

It is a super cooled liquid of silicate, it is amorphous in nature.

Raw material used for the formation of glass is sodium carbonate, calcium carbonate and sand.

Sudden cooling of molten glass make it brittle if cooled very slowly make it opaque.

The process of slow and uniform cooling is called annealing.

When glass is attacked by hydrofluoric acid, it is called etching of glass.

Coloured glass is obtained by adding certain metallic oxides or salts to the molten glass.

Types of glasses and their uses:

Soft glass (Soda Glass):

Mixture of sodium or calcium silicate.

Used in making of glass, mirrors and common glass ware etc.

Hard Glass:

Mixture of potassium and calcium silicates.

Resistant to the action of acids and used for making hard glass.

Pyrex glass (Borosilicate glass) :

Used by fusing a mixture of sand, lime, borax and alkali carbonates.

Used in making of pharmaceuticals containers.

Glass fiber:

Glass wool is an excellent heat insulator.

Used in insulating material in oven, refrigerator.