For the following concentration cell, to be spontaneous \(\mathrm{Pt}\left(\mathrm{H}_2\right) P_1\) atm.…
For the following concentration cell, to be spontaneous \(\mathrm{Pt}\left(\mathrm{H}_2\right) P_1\) atm. \(|\mathrm{HCl}| \mathrm{Pt}\left(\mathrm{H}_2\right) P_2\) atm. Which of the following is correct?
\(P_1=P_2\)
\(P_1 < P_2\)
\(P_1 > P_2\)
Can't be predicted
Solution
$\mathrm{Pt}\left(\mathrm{H}_2\right) \mathrm{P}_1$ atm. $|\mathrm{HCl}| \mathrm{Pt}\left(\mathrm{H}_2\right) \mathrm{P}_2$ atm.
For spontaneous reaction, $E_{\text {cell }}$ should be positive so $P_1 > P_2$
$E_{\text {cell }}=\frac{0.059}{2} \log \frac{P_1}{P_2}$
Also, if $P_1 > P_2$ oxidation occurs at L.H.S. electrode and reduction occurs at R.H.S. electrode.