Question

A compound which is prepared from gypsum has the property of hardening when mixed with a proper quantity of water. Identify the compound and write its chemical formula. Write the chemical equation for its preparation. Mention any one use of the compound.

Answer 1

The compound prepared from gypsum which has hardening property when mixed with water is "Plaster of Paris". The chemical formula of Plaster of Paris is ${\mathrm{CaSO}}_4.\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.{\mathrm{H}}_2\mathrm{O}$.
The balanced chemical equation for the preparation of Plaster of Paris is:
$2{\mathrm{CaSO}}_4.2{\mathrm{H}}_2\mathrm{O}\stackrel{\mathrm{heat}}{\to }2{\mathrm{CaSO}}_4.\frac{1}{2}{\mathrm{H}}_2\mathrm{O}+3{\mathrm{H}}_2\mathrm{O}$

In hospitals, it is used as a plaster for supporting the broken or fractured bones.