Q.

The standard cell potential of the following cell Zn|Zn(aq)2+||Fe(aq)2+|Fe is 0.32 V. Calculate the standard Gibbs energy change for the reaction Zn(s)+Fe(aq)2+Zn(aq)2++Fe(s)  (Given : 1 F = 96487 C)                          [2024]

1 -61.75 kJ mol-1  
2 +5.006 kJ mol-1  
3 -5.006 kJ mol-1  
4 +61.75 kJ mol-1  

Ans.

(1)

ΔG°=-nFEcell

Given, Ecell=0.32 V

and 1F = 96487 C

For the given reaction, n=2

ΔG°=-2×96487×0.32=-61751.68 J mol-1=-61.75 kJ mol-1