Problem: The nickel­cadmium battery cell has a standard potential of +1.20 V. The cell reaction is2 NiO(OH)(s) + Cd(s) + 2 H2O(l) → 2 Ni(OH)2(s) + Cd(OH)2(s).What is the standard free energy change (kJ) for this reaction?a. -347 kJb. +116 kJc. -116 kJd. +232 kJe. -232 kJ

FREE Expert Solution

We’re being asked to calculate for the standard free energy change, ΔG° (kJ) for this reaction:

2 NiO(OH)(s) + Cd(s) + 2 H2O(l) → 2 Ni(OH)2(s) + Cd(OH)2(s)     E°cell = +1.20 V

ΔG° can be calculated from the cell potential using the following equation:

$\overline{){\mathbf{∆}}{\mathbf{G}}{\mathbf{=}}{\mathbf{-}}{\mathbf{nFE}}{{\mathbf{°}}}_{{\mathbf{cell}}}}$

ΔG° = Gibbs Free Energy, J
n = # of e- transferred
F = Faraday’s constant = 96485 J/(mol e-)
cell = standard cell potential, V

First, let’s determine how many electrons were transferred from the cell reaction:

81% (165 ratings)
Problem Details

The nickel­cadmium battery cell has a standard potential of +1.20 V. The cell reaction is

2 NiO(OH)(s) + Cd(s) + 2 H2O(l) → 2 Ni(OH)2(s) + Cd(OH)2(s).

What is the standard free energy change (kJ) for this reaction?

a. -347 kJ
b. +116 kJ
c. -116 kJ
d. +232 kJ
e. -232 kJ