Question

Identify the correct statement.

• A. Plaster of Paris is obtained by the partial oxidation of gypsum.
• B. The percentage of plaster of calcium in gypsum is less than plaster of Paris.
• C. Gypsum is obtained by the plaster of Paris on heating.
• D. Plaster of Paris is obtained by the addition of water in gypsum.

Answer 1

Answer: (B)

The percentage of plaster of calcium in gypsum $ (CaS{{O}_{4}}.2{{H}_{2}}O) $ is less than plaster of Paris $ \left( CaS{{O}_{4}}.\frac{1}{2}{{H}_{2}}O \right) $ $ \underset{gypsum}{\mathop{2CaS{{O}_{4}}.2{{H}_{2}}O}}\,\xrightarrow[{}]{\Delta }\underset{plaster\text{ }of\text{ }Paris}{\mathop{{{(CaS{{O}_{4}})}_{2}}.{{H}_{2}}O}}\,+3{{H}_{2}}O $