Consider a cell based on the following half-reactions:

a. Draw this cell under standard conditions, labeling the anode, the cathode, the direction of electron flow, and the concentrations, as appropriate.

b. When enough \(\mathrm{NaCl}(s)\) is added to the compartment containing gold to make \(\left[\mathrm{Cl}^{-}ight]=0.10 \mathrm{M}\), the cell potential is observed to be \(0.31 \mathrm{~V}\). Assume that \(\mathrm{Au}^{3+}\) is reduced and that the reaction in the compartment containing gold is

\[\mathrm{Au}^{3+}(a q)+4 \mathrm{Cl}^{-}(a q) ightleftharpoons \mathrm{AuCl}_{4}^{-}(a q)\]

Calculate the value of \(K\) for this reaction at \(25^{\circ} \mathrm{C}\).

3+ Au + Au + 3e Fe+ + e Au Fe+ 8 = 1.50 V 8 = 0.77 V