Consider the following standard electrode potential values: $$\mathrm{Fe^{3+}(aq)}+e^-\rightarrow\mathrm{Fe^{2+}(aq)};\ E^{\circ}=+0.77\ \mathrm{V}$$ $$\mathrm{MnO_4^-(aq)}+8\mathrm{H^+}+5e^-\rightarrow\mathrm{Mn^{2+}(aq)}+4\mathrm{H_2O};\ E^{\circ}=+1.51\ \mathrm{V}$$ What is the cell potential for the redox reaction?

CBSE Class 12 · 2023 · Redox Reactions and ElectrochemistryMultiple Choice

Consider the following standard electrode potential values:

F e^{3 +} (aq) + e^{-} \to F e^{2 +} (aq); E^{\circ} = + 0.77 V

Mn O_{4}^{-} (aq) + 8 H^{+} + 5 e^{-} \to M n^{2 +} (aq) + 4 H_{2} O; E^{\circ} = + 1.51 V

What is the cell potential for the redox reaction?

Answer: (C)

MnO

_{4}^{-}

, with the higher reduction potential, is reduced (cathode); Fe

^{2 +}

is oxidised (anode).

E_{ce l l}^{\circ} = E_{c a t h o d e}^{\circ} - E_{an o d e}^{\circ} = 1.51 - 0.77

= + 0.74 V

CBSE Class 12 Board · 2023 · Single correct option