Pb(NO3)2 + 2 Zn → 2 Zn(NO3) + Pb
This is an oxidation-reduction (redox) reaction:
PbII + 2 e- → Pb0 (reduction)
2 Zn0 - 4 e- → 2 ZnII (oxidation)
2 NV + 2 e- → 2 NIV (reduction)
Pb(NO3)2 is an oxidizing agent, Zn is a reducing agent, Pb(NO3)2 is an oxidizing agent.