What is the reduction potential of a hydrogen gas electrode when pure hydrogen gas is at $1 \ atm$ pressure and the platinum electrode is in contact with an $HCl$ solution of $pH$ $1$ at $298 \ K$ (in $V$)?

If the concentration of a $Zn^{2+}$ solution is diluted $10$ times,what is the change in the potential of the $Zn/Zn^{2+}$ electrode?

Considering the cell $Cu | Cu^{2+} || Ag^{+} | Ag$,what happens to the $emf$ if the concentrations of both $Cu^{2+}$ and $Ag^{+}$ ions are increased by a factor of $10$?

$A$ solution containing $4.5 \ mM$ of $MnO_4^{-}$ and $15 \ mM$ of $Mn^{2+}$ shows $pH$ of $2$. The potential of the half-cell reaction is $......$. (Given: $\log 15 = 1.176$,$\log 4.5 = 0.653$,and standard potential of $MnO_4^{-} \longrightarrow Mn^{2+}$ is $1.51 \ V$) (in $V$)

What will be the $emf$ for the given cell $Pt|H_2(P_1)|H^{+}_{(aq)}||H_2(P_2)|Pt$?

The $EMF$ of a hydrogen electrode in terms of $pH$ is (at $1 \ atm$ pressure).