Question

What do you mean by the water of crystallization of substance? Describe the activity to show that blue copper sulfate contains water of crystallization.

Answer 1

Hint: The water of crystallization is caused by forming purified crystals from an aqueous solution. These crystals do not include contaminants. These crystals are easily affected by the heat.

Complete Step by step solution:
The water of crystallization refers to water that is found in the crystalline framework of a metal complex or a salt, which is not directly bonded to the metal cation.
The water of crystallization or the water of hydration is the water that occurs in the crystals. It is denoted as a hydrated compound $n{{H}_{2}}O$.
Let's consider an example gypsum is a soft mass having the formula \[CaS{{O}_{4}}.2{{H}_{2}}O\]. When we heat gypsum, plaster of Paris is formed by losing the water of crystallization. The Plaster of Paris is a hard mass with the formula ${{(CaS{{O}_{4}})}_{2}}.{{H}_{2}}O$.
Blue copper sulfate crystals which seem to be dry contain water of crystallization. When we heat the crystals, this water is removed and the salt turns white. If you moisten the crystals again with water, you will find that the blue color of the crystals reappears.
The above-mentioned step completely describes that blue copper sulfate contains water of crystallization.

Note: The water of crystallization is the fixed number of water molecules present in one formula unit of salt. Five water molecules are present in one formula unit of blue copper sulfate. The chemical formula for hydrated blue copper sulfate is \[CuS{{O}_{4}}.~5{{H}_{2}}O\] .