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Cadmium metal is placed in a solution of iron(II) ions, with E°(Cd²⁺/Cd) = -0.40 V and E°(Fe²⁺/Fe)…

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Cadmium metal is placed in a solution of iron(II) ions, with $E^\circ(\text{Cd}^{2+}/\text{Cd}) = -0.40\ \text{V}$ and $E^\circ(\text{Fe}^{2+}/\text{Fe}) = -0.44\ \text{V}$ . For the reaction $\text{Cd}(s) + \text{Fe}^{2+}(aq) \rightarrow \text{Cd}^{2+}(aq) + \text{Fe}(s)$ , find the standard emf, $\Delta G^\circ$ and $\log K$ . Does cadmium dissolve to any large extent?

Need a reminder? The key ideaShow

$\Delta G^\circ = -nFE^\circ$ , with $F = 96500\ \text{C/mol}$ , and $E^\circ = \dfrac{0.0591\ \text{V}}{n}\log K$ at $298\ \text{K}$ . A reaction with $E^\circ > 0$ has $\Delta G^\circ < 0$ and $K > 1$ . When half-reactions with different numbers of electrons are added, add the Gibbs energies, not the potentials.

The worked solution

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Cadmium metal is placed in a solution of iron(II) ions, with E°(Cd²⁺/Cd) = -0.40 V and E°(Fe²⁺/Fe)…

The worked solution

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