NCERT Problem 7.8 - Redox Reactions
Question: Explain why SO2 and H2O2 can act as both oxidising and reducing agents, whereas O3 and HNO3 are mainly oxidising agents.
Answer: S in SO2 (+4) and O in H2O2 (-1) have intermediate oxidation states. O3 and nitrate nitrogen are already at high oxidation state and mainly undergo reduction.
Full step-by-step NCERT solution with diagrams on Something by Zero.