Question

The emf \[\ce{E^\circ_\text{cell}}\] of the following reaction is 0.89 V.

\[\ce{3Sn^{4+} + 2Cr -> 3Sn^{2+} + 2Cr^{1+}}\]

Calculate the value of ΔG° for the reaction. Predict whether the above reaction will be spontaneous or not.

Answer 1

Half-cell reaction

\[\ce{Sn^{4+} + 2e^- -> Sn^{2+} \times 3}\]

\[\ce{Cr^{3+} + 3e^- -> Cr \times 2}\]

n = 6, ΔG° = - nFE°

= - 6 × 96500 × 0.89

ΔG° = - 515.311 kJ

The reaction will be spontaneous as the value of ΔG° is negative.