Question

If the reduction reaction has a reduction potential of 0.1 V, and the oxidation reaction has a reduction potential of -0.4V, and 2 electrons were transfered, what is the value of delta G expressed in terms of F?

Answer 1

Answer : The value of ΔG expressed in terms of F is, -1 F

Explanation :

First we have to calculate the standard electrode potential of the cell.

`E^o=E^o_(cathode)-E^o_(anode)`

or,

`E^o=E^o_(reduction)-E^o_(oxidation)`

`E^o=(0.1V)-(-0.4V)=+0.5V`

Now we have to calculate the standard cell potential.

Formula used :

`\Delta G^o=-nFE^o`

where,

`\Delta G^o` = Gibbs free energy = ?

n = number of electrons = 2

F = Faraday constant

`E^o` = standard e.m.f of cell = +0.5 V

Now put all the given values in this formula, we get the Gibbs free energy.

`\Delta G^o=-(2* F* 0.5)`

`\Delta G^o=-1F`

Therefore, the value of ΔG expressed in terms of F is, -1 F