Question

For the fuel cell reaction, $2H_2+O_2\to 2H_{2}O$, $\Delta G=-475kJ$.

The value of $E^o$ cell is:

• A. 1.23 V
• B. 2.46 V
• C. 0.615 V
• D. 0.31 V

Answer 1

The correct option is A 1.23 V

$2H_2+O_2⟶2H_{2}O$

$O_2+4H^{+}+4e^{-}⟶2H_{2}O$

Total electrons involved $=4$

$\Delta G^o=-nF{E}^o$

$-475\times 1000=-4\times 96500\times E^o$

$E^o=1.23V$

Hence, option A is correct.