What is the standard reduction potential $(E^o)$ for $Fe^{3+} \to Fe$ ? ............... $V$
Given that :
$Fe^{2+} + 2e^- \to Fe;$ $E^o_{Fe^{2+}/Fe} = -0.47 \ V$
$Fe^{3+} + e^- \to Fe^{2+};$ $E^o_{Fe^{3+}/Fe^{2+}} = +0.77 \ V$

If the standard reduction potentials of $Zn$, $Ni$, and $Fe$ are $-0.76 \text{ V}$, $-0.23 \text{ V}$, and $-0.44 \text{ V}$ respectively, determine the electrodes $X$ and $Y$ for the reaction $X(s) + Y^{+2}(aq) \rightarrow X^{+2}(aq) + Y(s)$ to be spontaneous.

Calculate the standard potential of a cell having the following electrode reactions:
$Cd_{(aq)}^{2+} + 2e^{-} \rightarrow Cd_{(s)}$ $E^{\circ} = -0.403 \ V$
$Zn_{(aq)}^{2+} + 2e^{-} \rightarrow Zn_{(s)}$ $E^{\circ} = -0.763 \ V$ (in $V$)

If the standard reduction potentials of four electrodes $A$, $B$, $C$, and $D$ are $+2.5 \text{ V}$, $+3.0 \text{ V}$, $-2.0 \text{ V}$, and $-1.5 \text{ V}$ respectively, in which case is the standard $emf$ of the cell maximum?

Which from the following is the correct relationship between standard Gibbs energy change and standard cell potential?

Calculate the standard electromotive force $(E^o_{cell})$ for the following cell: $Zn|Zn^{2+} (1 \ M)||I^{-} (1 \ M)|CuI|Cu$. Given the half-cell reactions:
$CuI_{(s)} + e^{-} \to Cu_{(s)} + I^{-}_{(aq)}$ ; $E^o = -0.17 \ V$
$Zn^{2+}_{(aq)} + 2e^{-} \to Zn_{(s)}$ ; $E^o = -0.76 \ V$ (in $V$)