MHT CET202526 Apr 2025Morning ShiftChemistryElectrochemistryActual
If E ^ ( Cu _ ( aq ) ⁺² Cu _ ( s ) )=+0 34 ~V . What is potential for Cu _ ( s ) Cu _ ( aq ) ⁺²(0 1 M )+2 e at 298 K ?
Options
- A+0.3696 V
- B-0.3696 V
- C+0.3104 V
- D-0.3104 V
Correct answer
D. -0.3104 V
Step-by-step solution
The standard reduction potential for Cu ²⁺ + 2e^- Cu _ (s) is given as +0.34 V , so the standard oxidation potential for the reverse reaction Cu _ (s) Cu ²⁺ + 2e^- is -0.34 V . Using the Nernst equation at 298 K with n = 2 and Q = [ Cu ²⁺] = 0.1 M : E = E^ - 0.0592 n Q = -0.34 - 0.0592 2 (0.1) Since (0.1) = -1 , this simplifies to: E = -0.34 + 0.0296 = -0.3104 V The potential for the reaction is thus -0.3104 V .