CGPET 2021 Solved Paper

The reaction with KMnO4 and sulphite is as follows :
MnO4−+5SO32−+6H+⟶2Mn2++5SO42−+3H2O
So, one mole of sulphite (SO32−) is needed to react with

2

5

mole of MnO4−according to given reaction.
Note 2 moles of MnO4− react with 5 moles of sulphite in acidic medium.