Question

what happens when a piece of iron metal is placed in copper sulphate solution

Answer 1

copper will be reduced and iron sulphate will be formed.

Answer 2

When a piece of iron metal is placed in copper solution, iron displaces copper from the sulphate solution leading to formation of ferrous sulphate and copper. CuSO4 + Fe ----> FeSO4 + Cu The blue colour of the solution changes to pale green and there is a reddish-brown deposit of copper. This is a displacement reaction in which a more reactive metal displaces a less reactive metal from its salt solution.