Use standard reduction potentials (shown below) to calculate the
potential of a nickel-cadmium cell that uses a basic electrolyte
that has a 3.2 M hydroxide concentration.
Cd(OH)2(s) + 2e- → Cd(s) + 2OH-(aq) Eº = -0.83 V
NiO(OH)s) + H2O(l) + e- → Ni(OH)2(s) + OH-(aq) Eº = 0.52 V
Oxidation : Cd(s) + 2OH⁻(aq) -------------> Cd(OH)₂(s) + 2e⁻ E° = -0.83 V
Reduction : NiO(OH)(s) + H₂O(l) + e⁻ ----------> Ni(OH)₂(s) +
OH⁻(aq) E° = +0.52 V
The overall equation is :
2NiO(OH)(s) + Cd(s) + 2H₂O(l) ------------> 2
Ni(OH)₂(s) + Cd(OH)₂ (s)
Standard potential of the nickel-cadmium cell,
E°cell = E°(red) - E°(oxid)
= 0.52 - (- 0.83)
E°cell = 1.35 V
Get Answers For Free
Most questions answered within 1 hours.