Question

Number of water molecules present in one formula unit of a salt is called__.

• A. water of hydration
• B. water of crystallisation
• C. evaporated water
• D. solid water

Answer 1

The correct option is B

water of crystallisation

The water of crystallization is the fixed number of water molecules present in one formula unit of a salt.
Eg; Five water molecules are present in one formula unit of copper sulphate. The chemical formula for hydrated copper sulphate is ${\text{CuSO}}_4.5{\text{H}}_2\text{O}$.