Question

Following two half cells form a complete cell which has $\Delta G ^{\circ}($ in $kJ )$ value
$2 H ^{+}+1 / 2 O _{2}+2 e ^{-} \rightarrow H _{2} O ; \quad E ^{\circ}=+1.23 V$
$Fe ^{2+}+2 e ^{-} \rightarrow Fe ( s )$ $E^{\circ}=-0.44 V$

• A. -122 kJ
• B. -222 kJ
• C. -322 kJ
• D. -422 kJ

Answer 1

Answer: (C)

$\Delta G^{0}=-n F E^{0}=-2 \times 96500 \times[1.23-(-0.44)] J$

$=-322310\, J =-322.31\, kJ$