Chemistry - Electrochemistry Question with Solution | TestHub

Cell reaction is:

$\text{Sn}(\text{s})+{\text{Pb}}^{+2}(\text{aq})\to {\text{Sn}}^{+2}(\text{aq})+\text{Pb}(\text{s})$

Apply Nernst equation:

${\text{E}}_{\text{cell }}={\text{E}}_{\text{cell }}^0-\frac{0.06}{2}\log \frac{\left[{\text{Sn}}^{+2}\right]}{\left[{\text{Pb}}^{+2}\right]}\mathrm{.....}\left(1\right)$

${\text{E}}_{\text{cell }}^0=-0.13+0.14=0.01\text{V}$

At equilibrium :${\text{E}}_{\text{cell }}^{}=0$Substituting in (1)

$0=0.01-\frac{0.06}{2}\log \frac{\left[{\text{Sn}}^{+2}\right]}{\left[{\text{Pb}}^{+2}\right]}$

$\Rightarrow \frac{1}{3}=\log \frac{\left[{\text{Sn}}^{+2}\right]}{\left[{\text{Pb}}^{+2}\right]}$

$\Rightarrow \frac{\left[{\text{Sn}}^{+2}\right]}{\left[{\text{Pb}}^{+2}\right]}=2.15$