When zinc pieces are are put in copper sulphate solution what happens?

Explanation -

Zinc is more reactive than copper. So, by adding zinc to CuSO4 solution, zinc displaces copper from copper sulphate & forms zinc sulphate solution. This is indicated by colour change from blue to colourless. CuSO4 solution has a blue colour while ZnSO4 solution is colourless.

Chemical equation -

Zn (s) + CuSO4 (aq) - > Cu (s) + ZnSO4 (aq).

Type of reaction -

It's a displacement reaction.

It's a redox reaction. Oxidation number of Cu decreases from 2 to 0 so it's reduced. Oxidation number of Zn increases from 0 to 2 so it's oxidised.