When two half-cells of electrode potential of E1o and E2o are combined to form a cell of electrode potential E3o(.n1,n2,n3 are the number of electrodes exchanged in first, second and third half-cell reactions), then

Question

When two half-cells of electrode potential of E1o and E2o are combined to form a cell of electrode potential E3o(.n1,n2,n3 are the number of electrodes exchanged in first, second and third half-cell reactions), then (A) E3o=E1o+E2o (B) E3o=E2o-E1o (C) E3o=(n1 E1o + n2 E2o/n3) (D) E3o=(n1 E1o - n2 E2o/n32)

Tardigrade Admin · Accepted Answer

As E° is non additive but Δ G° is additive Δ G3o=Δ G1o+Δ G2o -n3FE3o=-nFE1o-n2FE2o E3o=(n1 E1o + n2 E2o/n3)

Q. When two half-cells of electrode potential of $E_{1}^{o}$ and $E_{2}^{o}$ are combined to form a cell of electrode potential $E_{3}^{o} (n_{1}, n_{2}, n_{3}$ are the number of electrodes exchanged in first, second and third half-cell reactions), then

$E_{3}^{o} = E_{1}^{o} + E_{2}^{o}$

$E_{3}^{o} = E_{2}^{o} - E_{1}^{o}$

$E_{3}^{o} = \frac{n _{1} E _{1}^{o} + n _{2} E _{2}^{o}}{n _{3}}$

$E_{3}^{o} = \frac{n _{1} E _{1}^{o} - n _{2} E _{2}^{o}}{n _{3}^{2}}$

As $E^{\circ}$ is non additive but $Δ G^{\circ}$ is additive
$Δ G_{3}^{o} = Δ G_{1}^{o} + Δ G_{2}^{o}$
$- n_{3} F E_{3}^{o} = - n F E_{1}^{o} - n_{2} F E_{2}^{o}$
$E_{3}^{o} = \frac{n _{1} E _{1}^{o} + n _{2} E _{2}^{o}}{n _{3}}$

Q. When two half-cells of electrode potential of E1o​ and E2o​ are combined to form a cell of electrode potential E3o​(n1​,n2​,n3​ are the number of electrodes exchanged in first, second and third half-cell reactions), then

E3o​=E1o​+E2o​

E3o​=E2o​−E1o​

E3o​=n3​n1​E1o​+n2​E2o​​

E3o​=n32​n1​E1o​−n2​E2o​​