♡Plaster of Paris♡

• When gypsum is heated upto 373 K then it gets converted into plaster of paris.
• When POP is moxed with water it gets converted into solid mass.
• Use of plaster of Paris: Used for making fractured bones and constructing statues and pots..etc.

It is the compound of calcium which is used for plastering of lecture bones is calcium sulphate hemihydrate(calcium sulphate half- hydrate)

★ it is also called plaster of paris.

The formula of plaster of Paris is

CaSO4.1/2H2O

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the name plaster of Paris. came from that fact it was first of all made by heating gypsum which is mainly found in Paris..

it is commonly known as P.O.P.

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Chemical equation:

........................... heat to(100°c)

2(CaSO4.2H2O)-------------------->

2CaSO4.H2O. + 3H2O.

here reactant is gypsum.

it is heated on temperature 100°c.

then product obtained is plaster of Paris and water.

Precautions.

→ in the preparation of plaster of Paris heating of gypsum should be controlled carefully.

→ the temperature during the heating of gypsum should not be allowed to go above 100° c.

→ this is because if the gypsum is heated above 100 degree Celsius then its water of crystallization is eliminated and anhydrous calcium sulphate (CaSO4) called dead burnt plaster is formed.

→ The anhydrous calcium sulphate does not set like plaster of Paris on adding water.