The standard reduction potentials of the following electrodes are given .\ $\mathrm{Fe}^{3+} / \mat

Question

The standard reduction potentials of the following electrodes are given .\ $\mathrm{Fe}^{3+} / \mathrm{Fe}^{2+}=+0.77 \mathrm{~V}$,\ $\mathrm{Ag}^{+} / \mathrm{Ag}=+0.80 \mathrm{~V}, \quad \mathrm{I}_{2} / \mathrm{I}^{-}=+0.54 \mathrm{~V}$\ $\mathrm{Cu}^{2+} / \mathrm{Cu}=+0.34 \mathrm{~V}, \quad \mathrm{Br}_{2} / \mathrm{Br}^{-}=+1.09 \mathrm{~V}$\ Predict the feasible reaction(s) between the following species.\

Professor PC Thomas Classes · Answer

In the electrodes involving the two ions, the spontaneous reaction is oxidation at the electrode with lower $E^{\ominus}$ and the reduction at the higher $\mathrm{E}^{\ominus}$\ a) $\mathrm{Fe}^{3+}$ can be easily reduced (higher $\mathrm{E}^{	heta}$ ) I- can be easily oxidised (lower E ${ }^{9}$\ $	herefore$ the reaction is feasible\ b) $\mathrm{Cu}^{2+}$ has a lower $\mathrm{E}^{\ominus}$ value than $\mathrm{Ag}^{+}$.\ $	herefore \mathrm{Cu}^{2+}$ can not be reduced by Ag\ Similar is the case of ((C)\ In ((d) $\mathrm{Br}_{2}$ is easily reduced (higher $\mathrm{E}^{\ominus}$ )\ by $\mathrm{Fe}^{2+}$ (lower $\mathrm{E}^{\ominus}$ ) Hence the given change is not feasible\