UPSEE Solved Model Paper 5

The balanced chemical reactions (iconic reactions) for reduction K2Cr2O7 by Sn2+ are :
Cr2O72− + 14H++6e− → 2Cr3++7H2O
(Sn2+→Sn4++2e−) × 3
Blaanced ner reaction : 3Sn2++Cr2O72−+14H+ → 3Sn4++2Cr3++7H2O
Thus according to the balanced reaction : 1 mole of Cr2O72− will be reduced by 3 moles of Sn2+
Thus 1 mole of Sn2+ will reduce = 1/3 moles of Cr2O72−