Q. For the reduction of silver ions with copper metal, the standard cell potential was found to be +0.46 V at 25°C. The value of standard Gibbs energy, ΔG° will be (F = 96500 C mol⁻¹)
A) −98.0 kJ
B) −89.0 kJ
C) −89.0 J
D) −44.5 kJ
Explanation
[Solution from source] Cu + 2Ag⁺ → Cu²⁺ + 2Ag involves n = 2. ΔG° = −nFE° = −2 × 96500 × 0.46 = −88780 J ≈ −89.0 kJ. Taking n = 1 gives −44.5 kJ; −89.0 J has the wrong unit. Answer (2).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.