Question

When SO2 gas is passed through saturated solution of H2S, the following reaction occurs SO2 + 2H2S → 2 H2O + 3S In this reaction, which substance is oxidized and which one is reduced.

Answer 1

see it is very simple. first you need to see which substance has hydrogen before reaction and which one has later. thus H2S has hydrogen. Now see which product has hydrogen, i.e. H2O. now see where does O belong from. O belongs from SO2. thus SO2 is reduced to H2O and H2S is oxidised to H2O. always remember that oxidisation is reverse of reduction.

hope this helps you!! :)

Answer 2

SO2(oxidation state of S is +4) to 2S(oxidation state of S is 0)

reduction process. SO2 is a oxidising agent.