Question

how can you show with an activity the presence of water in blue copper sulphate crystals

Answer 1

We will take a test tube and will heat copper sulphate crystals in it.You will observe that from these crystals the water gets evaporate.
And when we mix this left copper sulphate with water it will again form blue coloured crystals.

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.