JEE Main levelNumerical answerDifficulty 2 of 3ec064
E∘(CeX4+/CeX3+)=1.61V and E∘(FeX3+/FeX2+)=0.77V. For the reaction FeX2++CeX4+FeX3++CeX3+ at 298 K, log10K (nearest integer) is. Take F2.303RT=0.0591V.
Numerical answer type.
Answer: 14
Ecell∘=1.61−0.77=0.84V with n=1. logK=0.0591nE∘=0.05910.84=14.2≈14. The very large K (∼1014) is why CeX4+ titration of FeX2+ goes essentially to completion.