Question

Using the standard electrode potential, predict if the reaction between the following is feasible:

Fe³⁺(aq) and I^–(aq)

Answer 1

The possible reaction between Fe³⁺_(aq) + I^–_(aq)is given by,

\[\ce{2Fe^{3+}_{(aq)} + 2I-_{(aq)} -> 2Fe^{2+}_{(aq)} + I_{2(s)}}\]

Oxidation half equation:	\[\ce{2I-_{(aq)} -> I_{2(s)} + 2e-}\]; E° = - 0.54 V
Reduction half equation:	\[\ce{[Fe^{3+}_{aq}) + e- -> Fe^{2+}_{(aq)}] × 2}\]; E° = + 0.77 V
	\[\ce{2Fe^{3+}_{(aq)} + 2I-_{(aq)} -> 2Fe^{2+}_{(aq)} + I_{2(s)}}\]; E° = + 0.23 V

E° for the overall reaction is positive. Thus, the reaction between `"Fe"_(("aq"))^(3+)` and `"I"_(("aq"))^(-)` is feasible.