The $emf$ of a galvanic cell constituted with the electrodes $Zn^{2+} | Zn$ $(-0.76 \ V)$ and $Fe^{2+} | Fe$ $(-0.41 \ V)$ is

Which statement is correct for $\Delta G$ and $E_{cell}$ for a cell reaction?

Given:
$Co^{3+} + e^- \longrightarrow Co^{2+}; E^o = 1.81 \ V$
$Pb^{4+} + 2e^- \longrightarrow Pb^{2+}; E^o = + 1.67 \ V$
$Ce^{4+} + e^- \longrightarrow Ce^{3+}; E^o = + 1.61 \ V$
$Bi^{3+} + 3e^- \longrightarrow Bi; E^o = + 0.20 \ V$
Oxidizing power of the species will increase in the order:

At ${25 \, ^\circ C}$,the standard reduction potentials for $Li^+/Li$,$Ba^{2+}/Ba$,$Na^+/Na$,and $Mg^{2+}/Mg$ are $-3.05 \, V$,$-2.73 \, V$,$-2.71 \, V$,and $-2.36 \, V$ respectively. Which of the following is the strongest oxidizing agent?

$K, Ca$ and $Li$ metals may be arranged in the decreasing order of their standard electrode potentials as

Which metal does not give the following reaction? $M + \text{water} \rightarrow \text{oxide or hydroxide} + H_2$