Question

Plaster of Paris should be stored in a moisture-proof container. Explain why?

Answer 1

The Plaster of Paris should be stored in a moisture-proof container, as it absorbs moisture and turns into hard substance (Gypsum) as shown in following chemical equation.

\[\ce{\underset{Plaster of Paris}{CaSO4. 1/2 H2O} + 3/2 H2O -> \underset{Gypsum}{CaSO4.}2H2O}\]