8.14 Consider the reactions :
Why does the same reductant, thiosulphate react differently with iodine and bromine?
oxidizing power order
Bromine is a stronger oxidizing agent than iodine. So in the case of bromine (avg. oxidation number of sulphur is changed from +2 to +6)
and in case of iodine it (+2 to +2.5). So that's why thiosulphate reacts differently with bromine and iodine.