What is the use of plaster of Paris?

The formula of Gypsum is CaSO4.2H2O. When heated to 120°C, the Plaster of Paris is formed. In this process, three-fourths of the crystalline water present in the gypsum is separated.

2[CaSO4.2H2O] → (CaSO4)2.H2O + 3H2O


It is a white colored powder.

Water effect: The plaster absorbs the water and forms gypsum which hardens. This whole action is called the solidification of plaster. This property of the freezing of plaster is very useful.

(CaSO4)2.H2O + 3H2O → 2[CaSO4.2H2O]

Effect of heat: On heating, the Plaster of Paris to 200°C, all the crystalline water present in it is removed and the material obtained is called dead burnt.

(CaSO4)2.H2O → 2CaSO4 + H2O

Calcium sulfate is reduced to calcium oxide and sulfur dioxide after heating over 400°C.

2CaSO4 → 2CaO + 2SO2 + O2

What is the use of plaster of Paris?

Plastering is used to add broken bones in hospitals.

Blooms and sculptures are made from Plaster of Paris.

Used for making chalk.

Useful in paper factories. Used to make teeth plastering.

Types of Plaster of Paris

There is the most common types of Plaster of Paris are Cement, Gypsum, and Lime.

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