Question

Equation for plaster of why plaster of paris is called as dead burnt plaster

Answer 1

When plaster of Paris CaSO4.1/2 H2O is heated above 393 K, its water of crystallisation is lost and anhydrous Calcium sulphate is left that is known as a dead burnt plaster.

Answer 2

Explanation:

$\huge \bf \red{ \mid{ \overline{ \underline{ANSWER}}} \mid}$

$\bf{plaster \: of \: paris}$

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.