In: Chemistry
using equation, G=Go+RT ln Q [Q=reaction quotient,at equilibrium G=0 and Q=K]
Go=-RT ln K
R=8.314 J/K.mol (universal gas constant)
T=25+273=298K
Go=-(8.314 J/K.mol)*298K ln (5.0*10^-6)=-(8.314 J/K.mol)*298K *2.030 log (5.0*10^-6)=30246.87 J/mol=30.246 KJ/mol
Also Go=-nFEocell
30246.87 J/mol=-(1mol electron)*(96485 C/mol)*Eocell [F=faraday's constant, C=J/V]
Eocell=-30246.87J/96485 J/V=-0.31V
b)
Go=-(8.314 J/K.mol)*298K ln (0.065)=-(8.314 J/K.mol)*298K *2.030 log (0.065)=6773.336 J/mol=Go
for n=2 mol
Go=6773.336 J/mol* 2 mol =13546.672 J/mol=13.546 KJ/mol
Also Go=-nFEocell
6773.336 J/mol=-(2mol electron)*(96485 C/mol)*Eocell [F=faraday's constant, C=J/V]
Eocell=-6773.336J/96485 J/V=-0.070 V