Question

A fuel cell designed to react grain alcohol with oxygen has the following net reaction:

Answer 1

Answer:

b. E = 2,28V

Explanation:

The maximum work is the same than ΔG. As ΔG could be written as:

ΔG = nFE (1)

Where n is moles of electrons transferred, F is faraday constant (96485 J/Vmol) and E is the voltage of the cell.

For the reaction:

CH₃OH(l) + ³/₂O₂(g) → CO₂(g) + 2H₂O(l)

The oxidation state of C in CH₃OH is -2 but in CO₂ is +4, that means transferred electrons are +4 - -2 = 6e⁻

Replacing in (1):

1320x10³ J = 6mol e⁻×96485J/Vmol×E

E = 2,28V

I hope it helps!