Question

What is meant by water of crystallization?describe an activity to show that blue copper sulphate crystals contain water of crystallisation?​

Answer 1

Annyeonghaseyo

Answer:

It is the fixed no. of molecules of water present in salt's one formula unit. Or we can say that water stoichiometrically bound into crystal.

For example:-

CuSO. (hydrated copper sulphate)

Explanation:

We need copper sulphate powder, sulphuric acid, water.

step.1

first take approximately 200ml. of water in a beaker.

step.2

Now, add dilute sulphuric acid to it.

step.3

Then this solution will be heated and copper sulphate powder will be added slowly, till saturated solution is formed.

step.4

Wait till Crystals of copper separate out.

Answer 2

AIM - To determine the water of crystallization.

Materials we need - copper sulphate crystals, test tube holder, burner, boiling tube.

Procedure - ★ heat few crystals of copper sulphate in a dry boiling tube.

★we will observe that on heating blue crystals of copper sulphate, it becomes colourless and few drops of water are seen on the test tube.

★ then, on adding few drops of water to the heated copper sulphate, the blue colour of copper sulphate reappears.

the water of crystallisation is the fixed number of water molecules present in one formula unit of salt.