Question

When blue salt of copper sulphate is heated it becomes colorless explain why?

Answer 1

When blue salt of copper sulphate i.e. CuSO4 is heated, it becomes colorless because the salt strongly looses all the water of crystallization, which leads to the formation of anhydrous copper sulphate which is white in colour.

Water of crystallization is the fixed number of water molecules present in one formula unit of saly. CuSO4 has 5 water molecules.