Q6 / 95 · NTA Abhyas (JEE Main) 2020 · Chemistry · s Block Elements

Identify the correct statement

Correct answer
A
Gypsum contains a lower percentage of calcium than plaster of paris
B
Gypsum is obtained by heating plaster of paris
C
Plaster of paris can be obtained by hydration of gypsum
D
None of these

Solution

Gypsum is

2 {CaSO}_{4} \cdot 2 H_{2} O

Plaster of paris is

{CaSO}_{4} \cdot \frac{1}{2} H_{2} O

Hence, Gypsum contains a lower percentage of calcium than plaster of paris.

Hence, the correct answer is option: 'A'.