For hydrogen - oxygen fuel cell at one atm and 298 K H2(g)+ (1/2) O2(g) → H2O(l) ; Δ G°=-240 kJ E° for the cell is approximately, (Given F = 96,500 C)

Question

For hydrogen - oxygen fuel cell at one atm and 298 K H2(g)+ (1/2) O2(g) → H2O(l) ; Δ G°=-240 kJ E° for the cell is approximately, (Given F = 96,500 C) (A) 1.25 V (B) 1.26 V (C) 2.48 V (D) 2.5 V

Tardigrade Admin · Accepted Answer

From Δ G°=-n F E° where, n= number of moles of electrons transferred =2 ⇒ F=96500 C Δ G°=-240 kJ =-240 × 1000 J ∴ E°=(-240000/-2 × 96500)=1.24 V

Q. For hydrogen - oxygen fuel cell at one $a t m$ and $298 K$
$H_{2} (g) + \frac{1}{2} O_{2} (g) \to H_{2} O_{(l)}; Δ G^{\circ} = - 240 k J$
$E^{\circ}$ for the cell is approximately, (Given $F = 96, 500 C$ )

$1.25 V$

$1.26 V$

$2.48 V$

$2.5 V$

From $Δ G^{\circ} = - n F E^{\circ}$

where, $n =$ number of moles of electrons

transferred $= 2$

$\Rightarrow F = 96500 C$

$Δ G^{\circ} = - 240 k J = - 240 \times 1000 J$

$∴ E^{\circ} = \frac{- 240000}{- 2 \times 96500} = 1.24 V$

Q. For hydrogen - oxygen fuel cell at one atm and 298K H2​(g)+21​O2​(g)→H2​O(l)​;ΔG∘=−240kJ E∘ for the cell is approximately, (Given F=96,500C)

1.25V

1.26V

2.48V

2.5V