Draw the non-degenerate 3d orbitals in a ${\mathrm{Ni}}^{+}$ ion on a diagram. The electrons should be shown in the configuration that gives the lowest possible energy.

Using the standard electrode potentials given below, explain why magnesium $\left(\mathrm{Mg}\right)$ can displace silver ions $\left({\mathrm{Ag}}^{+}\right)$ from a solution of silver nitrate.

$$\begin{gathered} {\mathrm{Mg}}^{2+}\left(\mathrm{aq}\right) + 2{\mathrm{e}}^{-} \rightleftharpoons \mathrm{Mg}\left(\mathrm{s}\right), (\mathrm{E}° = -2.37 \mathrm{V}) \\ {\mathrm{Ag}}^{+}\left(\mathrm{aq}\right) + {\mathrm{e}}^{-} \rightleftharpoons \mathrm{Ag}\left(\mathrm{s}\right), (\mathrm{E}° = +0,80 \mathrm{V}) \end{gathered}$$

Write a general set of rules to derive the expression for the equilibrium constant, ${\mathrm{K}}_{\mathrm{C}\text{'}}$ for a reaction such as:

$\mathrm{mA}\left(\mathrm{aq}\right) + \mathrm{nB}\left(\mathrm{aq}\right) \rightleftharpoons \mathrm{pC}\left(\mathrm{aq}\right) + \mathrm{qD}\left(\mathrm{aq}\right)$