Chemistry, asked by Kingmanishkumar2819, 1 year ago

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

Answers

Answered by gadakhsanket
81
Hey dear,

● Answer -
E° = 1.096 V

● Solution -
Combustion of pentane in fuel cell is shown by -
C5H12 + 8O2 --> 5CO2 + 6H2O
Here , n = 32 e-

Standard free energy of reaction is calculated by -
∆G° = ∆G(products) ∆G(reactants)
∆G° = 5∆Gf(CO2) + 6∆Gf(H2O) - ∆Gf(C5H12) - 8∆Gf(O2)
∆G° = 5×(-394) + 6(-237) - (-8) - 8(0)
∆G° = -3384 kJ

EMF of a cell is calculated by -
E° = -∆G° / nF
E° = -(-3384×10^3) / (32×96500)
E° = 1.096 V

Therefore, E° for pentane-oxygen cell is 1.096 V.

Hope this helped...




ashubh: how n=32 electrons please explain
shaileydipen: Same doubt, pls explain
gadakhsanket: cauz 1 O2 consumes 4e- in combustion
Answered by zikra0442
2

Explanation:

hope this will help you

Attachments:
Similar questions