2 Fe0 + 3 CuIISO4 2 (FeIII)3+ + 3 Cu0 + 3 SO42-

This is an oxidation-reduction (redox) reaction:

3 CuII + 6 e- 3 Cu0 (reduction)

2 Fe0 - 6 e- 2 FeIII (oxidation)

CuSO4 is an oxidizing agent, Fe is a reducing agent.