MHT CET202523 Apr 2025Morning ShiftChemistryElectrochemistryActual
Standard potential of electrode reaction Cu ⁺² _ ( aq ) +2 e Cu _ ( s ) is +0.34 V . What is standard potential of reaction 2 Cu _ ( s ) 2 Cu _ ( aq ) ⁺²+4 e ?
Options
- A+0.68 ~V
- B-0.68 ~V
- C+0.34 ~V
- D-0.34 ~V
Correct answer
D. -0.34 ~V
Step-by-step solution
The standard potential for the reduction reaction Cu ²⁺_ ( aq ) + 2e⁻ Cu _ ( s ) is given as E^ = +0.34 V . To find the standard potential for the reaction 2 Cu _ ( s ) 2 Cu ²⁺_ ( aq ) + 4e⁻ , note that this represents an oxidation process. Reversing a reaction changes the sign of E^ , and since E^ is an intensive property, scaling the stoichiometry does not affect its value. Therefore, the standard electrode potential remains E^ = -0.34 V , corresponding to option D . The correct answer is D .