MHT CET202522 Apr 2025Morning ShiftChemistryElectrochemistryActual
If E ^ ( Mg _ ( aq) ) ⁺² Mg _ ( s ) )=-2 37 ~V . What is potential for Mg _ ( s ) Mg ⁺²(0.01 M )+2 e at 298 K ?
Options
- A+2 3108 ~V
- B-2 3108 ~V
- C+2.4292 ~V
- D-2.4292 ~V
Correct answer
C. +2.4292 ~V
Step-by-step solution
Oxidation Potential via the Nernst Equation Given: Mg _ ( s ) Mg ⁺²(0.01 , M ) + 2 e , with standard reduction potential E ^ ( Mg _ ( aq ) ⁺² Mg _ ( s ) ) = -2.37 , V . The standard oxidation potential is the negative of the reduction potential: E^ _ ox = -(-2.37) = +2.37 , V . The reaction quotient is Q = [ Mg ⁺²] = 0.01 = 10⁻² , since the solid magnesium has unit activity. Using the Nernst equation at 298 , K : E = E^ - 0.0592 n Q with n = 2 electrons transferred: E = 2.37 - 0.0592 2 (10⁻²) = 2.37 - 0.0296 (-2) E