Question

The efficiency of fuel cell is given by the expression, $\eta$ is

• A. $\eta=-\frac{ nF E _{\text {cell }}}{\Delta H } \times 100$
• B. $\eta=-\frac{n F E_{\text {cell }}}{\Delta S} \times 100$
• C. $\eta=-\frac{ nFE _{\text {cell }}}{\Delta A } \times 100$
• D. None of the above

Answer 1

Answer: (A)

Efficiency of fuel cell is $\eta=-\frac{ nFE _{\text {cell }}}{\Delta H } \times 100$.
The thermodynamic efficiency of the fuel cell is the ratio of the electrical free energy to the enthalpy change of the reaction.
$\eta=\frac{\Delta G }{\Delta H } \times 100$
Also, $\Delta G =- nFE _{\text {cell }}$