The standard reduction potentials for the and electrodes are and respectively. For the specific cell — Electrochemistry Chemistry Question
Question
The standard reduction potentials for the $Fe^{2+}/Fe$ and $Sn^{2+}/Sn$ electrodes are $-0.44\text{ V}$ and $-0.14\text{ V}$ respectively. For the specific cell reaction $Fe^{2+}(aq) + Sn(s) \rightarrow Fe(s) + Sn^{2+}(aq)$, calculate the standard electromotive force ($E^\circ_{cell}$) in Volts.
💡 Solution & Explanation
In the provided redox reaction, $Sn$ undergoes oxidation to $Sn^{2+}$ (acting as the anode) and $Fe^{2+}$ undergoes reduction to $Fe$ (acting as the cathode). The standard cell potential is computed as $E^\circ_{cell} = E^\circ_{cathode} - E^\circ_{anode} = E^\circ_{Fe^{2+}/Fe} - E^\circ_{Sn^{2+}/Sn} = -0.44\text{ V} - (-0.14\text{ V}) = -0.30\text{ V}$. The negative sign confirms the reaction is non-spontaneous as written.