Kohlrausch's law states that at

Standard free energies of formation (in kJ/mol) at 298 K are $$-$$237.2, $$-$$ 394.4 and $$-$$8.2 for H₂O_(l), CO_2(g) and pentane _(g) respectively. The value of E^o_cell for the pentane-oxygen fuel cell is

On the basis of the following E^o values, the strongest oxidizing agent is
[Fe(CN)₆]^4$$-$$ $$ \to $$ [Fe(CN)₆]^3$$-$$ + e^$$-$$;  E^o = $$-$$0.35 V

Fe²⁺ $$ \to $$ Fe³⁺ + e^$$-$$;  E^o = $$-$$0.77 V

The efficiency of a fuel cell is given by