Which substance is the reducing agent in this reaction? 2KMnO4+3Na2SO3+H2O→2MnO2+3Na2SO4+2KOH

Question

anonymous · Answer

Na2SO3 is the reducing agent, because sulphur in it gets oxidised. Also MnO4- is an oxidising agent and itself gets reduced, so the other substance has to be the reducing agent.

anonymous · Answer

Every oxygen always has a charge of -2 by default except in some very rare cases. so: Sulphur in SO3(2-) has a charge of +4, while in SO4(2-)  it has a charge of +6 and that shows that it got oxidised (oxidation number increased, so it gave up its electrons and acted as a reducing agent to reduce the sodium permanganate ;)