Question

what do you observe when blue vitriol is heated?

Answer 1

The formula of blue vitriol is CuSO₄.5H₂O .

The water molecules are in loose chemical combination with the substance.

Hence this is typically called water of crystallization.

What do we observe when this substance is heated ?

The substance was originally blue in colour.

If we heat it , it becomes white powder.

This is shown in the attachment.

As the substance loses its water of crystallisation , its colour changes from blue to white.