Question

Write the method of preparation, chemical name and chemical formula of Plaster of Paris.

Answer 1

Plaster of Paris:
Preparation: Plaster of Paris is formed by heating gypsum $\left(CaS{O}_4.2H_{2}O\right)$ at ${100}^o$C.
$\underset{Gupsum}{CaS{O}_4.2H_{2}O}\stackrel{{100}^{o}C}{\underset{\Delta }{\to }}\underset{PlasterofParis}{CaS{O}_4.\frac{1}{2}{H}_{2}O}+\underset{water}{1\frac{1}{2}{H}_{2}O}$
Chemical Name: Calcium sulphate hemihydrate.
Chemical Formula: $CaS{O}_4\frac{1}{2}{H}_{2}O$.