Use the tabulated half-cell potentials below to calculate ΔG° for the following balanced redox reaction.
Pb²⁺(aq) + Cu(s) → Pb(s) + Cu²⁺(aq)

Question

Use the tabulated half-cell potentials below to calculate ΔG° for the following balanced redox reaction. Pb²⁺(aq)+ Cu(s)→ Pb(s)+ Cu²⁺(aq) A)-41 kJ B)-0.47 kJ C)46 kJ D)91 kJ E)-21 kJ

Quizplus · Accepted Answer

1. Write the half-reactions for each species:

PbS + 2e- → Pb + S2- E° = -0.16 V
Cu2+ + 2e- → Cu E° = +0.34 V
CuS + e- → Cu + S2- E° = -0.84 V

2. Add up the redox reactions:

PbS + 2Cu2+ + 2e- → Pb + 2CuS E° = -0.66 V

3. Calculate ΔG° using the formula:

ΔG° = -nFE°

Where n is the number of electrons transferred (2 in this case) and F is the Faraday constant (96,485 C/mol)

ΔG° = -2 * 96,485 * (-0.66) = 91 kJ

Therefore, the best choice is D.

Use the Tabulated Half-Cell Potentials Below to Calculate ΔG° for the Following