Question

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

 Br₂(aq) and Fe²⁺(aq)

Answer 1

The possible reaction between `"Be"_(2("aq"))` and `"Fe"_("aq")^(2+)` is given by,

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

Oxidation half equation:	\[\ce{Fe^{2+}_{ (aq)} -> Fe^{3+}_{ (aq)} + e-]× 2}\]; E° = - 0.77 V
Reduction half equation:	\[\ce{Br_{2(aq)} + 2e- -> 2Br^{-}_{ (aq)}}\]; E° = + 1.09 V
	\[\ce{Br_{2(aq)} + 2Fe^{2+}_{ (aq)} -> 2Br^{-}_{ (aq)} + 2Fe^{3+}_{(aq)}}\]; E° = - 0.32 V

Here, E° for the overall reaction is positive. Hence, the reaction between `"Br"_(2("aq"))` and `"Fe"_(("aq"))^(2+)` is feasible.