Standard free energies of formation (in KJ/mol) at 298K are -237.2, -394.4, and -8.2 for H2O(l), CO2(g) and pentane (g) respectively. The value of E(standard)cell for pentane oxygen fuel cell is?

1- 0.0968V 2- 1.968V

3- 2.0968V 4- 0.059V

​C5H12(g) + 8O2(g) → 5CO2(g) + 6H2O (l)
ΔG0(298K) = 5(–394.4) + 6(–237.2) – (–8.2) = –3387 × 103 J/mole
ΔG0=  - nFE°cell
n = ​the number of electrons per mole reaction
n= 5x4 + 6X2 = 32
ΔE°cell = (3387 x 103)/(32 x 96500)
 = 1.0968 V

  • 44
What are you looking for?