In a cell reaction
$Cu_{(s)} + 2Ag^{+}_{(aq)} \to Cu^{2+}_{(aq)} + 2Ag_{(s)}$
$E_{cell}^o = + 0.46 \ V$.
If the concentration of $Cu^{2+}$ ions is doubled,then $E_{cell}^o$ will be

Which metal cannot produce $H_2$ gas by reaction with $HCl$ solution?
$E^0_{Fe^{2+}/Fe} = -0.44 \ V$
$E^0_{Cu^{2+}/Cu} = +0.34 \ V$
$E^0_{Ni^{2+}/Ni} = -0.25 \ V$
$E^0_{Zn^{2+}/Zn} = -0.76 \ V$

For the following cell,the standard potential of the copper electrode is $0.337 \ V$ and the standard cell potential is $0.463 \ V$ for the reaction $Cu|Cu^{2+}(1 \ M)||Ag^{+}(1 \ M)|Ag$. What is the standard potential of the silver electrode (in $V$)?

Which of the following statements is false for $Hg$?

$Cr_2O_7^{2-} + I^{-} \to I_2 + Cr^{3+}$
$E^0_{cell} = 0.79 \ V$
$E^0_{Cr_2O_7^{2-}} = 1.33 \ V$,$E^0_{I_2}$ is ........... $V$

For the half-cell $Zn^{2+} | Zn$,the standard electrode potential $E^{\circ}$ is $-0.76 \ V$. What is the $e.m.f.$ of the cell $Zn_{(s)} | Zn^{2+}_{(aq)} (1 \ M) || 2H^{+}_{(aq)} (1 \ M) | H_{2(g)} (1 \ atm)$ in $V$?