Consider the equilibrium obtained by electrically connecting zinc-amalgam (Zn(Hg)) and HgO electrodes in mercury cell,  $Zn\left(Hg\right)+Hg{O}_{\left(s\right)}\underset{ }{\rightleftharpoons }Zn{O}_{\left(s\right)}+H{g}_{\left(l\right)}$  Under this equilibrium what is the relation between the potential of the Zn(Hg) and HgO electrodes measured against the standard hydrogen electrode?