The name plaster of Paris came from the fact that it was first of all made by heating gypsum which was mainly found in Paris. The compound plaster of Paris is prepared by heating gypsum at 120oC.
CaSO4.2H2O → CaSO4.1/2H2O + 3/2H2O
The chemical formula for the plaster of Paris is (CaSO4) H2O and is better known as calcium sulfate hemihydrate.
Applications of plaster of Paris
- Plaster of Paris is used by doctors for supporting fractured bones in the right position.
- It is used for making toys and decorative materials.
- It is also used for increasing smoothness of surfaces.