Question

Why colour copper sulphate is change when zinc rod is dipped in it?

Answer 1

As copper is less reactive than zinc sulphate trancefers from copper to zinc by a displacement reaction.

Answer 2

When we observe in the reactivity series we find that zinc(Zn) is more reactive than copper(Cu).

Again,we know that the colour of copper sulphate(CuSO4)is blue.But, when zinc rod is dipped in a solution of copper sulphate(CuSO4), then, zinc being more reactive than copper,displaces it from its compound and forms zinc sulphate(ZnSO4) whose colour is not blue.