Given that $\mathrm{E}_{\mathrm{Fe}^{2+} / \mathrm{Fe}}^{\mathrm{o}}=-0.44 \mathrm{V}$ and $\mathrm{E}_{\mathrm{Fe}^{3+} / \mathrm{Fe}^{2+}}^{\mathrm{o}}=0.77 \mathrm{V}$, the $\mathrm{E}_{\mathrm{Fe}^{3+} / \mathrm{Fe}}^{\mathrm{o}}$ is :
(a)1.21 V
(b)0.33 V
(c)-0.036 V
(d)0.036 V
Answer
SELF-PRACTICE — the source book printed no answer.
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