A platinum electrode immersed in a solution containing and ions is connected to a…

CHEMISTRY · Subjective · AP · Chemistry · Thermodynamics and Electrochemistry · Thermodynamics and Electrochemistry

Problem

A platinum electrode immersed in a solution containing

\mathrm{Fe}^{3+}

and

\mathrm{Fe}^{2+}

ions is connected to a standard hydrogen electrode (SHE,

P_{H_2}=1.00\,\text{atm}

[\mathrm{H}^{+}]=1.00\,\text{M}

). At

25\,^\circ\text{C}

the cell potential is

0.165\,\text{V}

, and the iron electrode acts as the cathode. The standard reduction potential for

\mathrm{Fe}^{3+}+e^{-}\to\mathrm{Fe}^{2+}

0.77\,\text{V}

. Determine the ratio

[\mathrm{Fe}^{2+}]/[\mathrm{Fe}^{3+}]

in the iron solution.