Question

The efficiency of a cell is 60%. Its cell reaction is $A\left(s\right)+B^{2+}(aq.)\to A^{2+}(aq.)+B;\Delta H=-240kJ$. The standard electrode potential of cell is?

• A. 0.746 V
• B. 0.37 V
• C. 1.48 V
• D. 2.96 V

Answer 1

The correct option is A

0.746 V

$\eta =\frac{\Delta G}{\Delta H}=\frac{60}{100}\Delta G=\frac{-60\times 240\times {10}^3}{100}=-144000\Delta G=-\eta FE\Rightarrow E=\frac{144000}{2\times 96500}=0.746V$