1. Tardigrade
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  3. Chemistry
  4. The efficiency of a fuel cell is 80 % and the standard the heat of reaction is -300 kJ. The reaction involves two electrons in redox change. E ominus for the cell is

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Q. The efficiency of a fuel cell is $80 \%$ and the standard the heat of reaction is $-300 \,kJ$. The reaction involves two electrons in redox change. $E^{\ominus}$ for the cell is

Electrochemistry

Solution:

Efficiency $=\frac{\Delta G^{\ominus}}{\Delta H^{\ominus}}=-\frac{n E^{\ominus}F }{\Delta H}=80$
$E^{\ominus}=\frac{80 \times(-300) \times 10^3}{2 \times 96500 \times 100}=1.24 \,V$