Based on the given standard electrode potentials,identify the metal that can be displaced from its salt solution by all other metals listed.
$E^o Zn^{2+}/Zn = -0.76 \ V, E^o Cu^{2+}/Cu = +0.34 \ V$
$E^o Ag^+/Ag = +0.80 \ V, E^o Co^{2+}/Co = -0.28 \ V$

$A$ cell reaction is spontaneous when:

The standard electrode potentials of two half-cells are given as: $Ni^{2+}_{(aq)} + 2e^{-} \rightarrow Ni_{(s)}$; $E^o = -0.25 \ V$ and $Zn^{2+}_{(aq)} + 2e^{-} \rightarrow Zn_{(s)}$; $E^o = -0.76 \ V$. What is the standard $emf$ of the cell formed by connecting these two half-cells in $volt$?

What is the procedure to determine the cell potential?

The relation between $\Delta G$ and $E$ for a cell is given by $\Delta G = -nFE$. Which of the following conditions must be satisfied for the cell reaction to be spontaneous?

Given the standard electrode potentials:
$K^{+} / K = -2.93 \, V$,$Ag^{+} / Ag = 0.80 \, V$
$Hg^{2+} / Hg = 0.79 \, V$
$Mg^{2+} / Mg = -2.37 \, V$,$Cr^{3+} / Cr = -0.74 \, V$
Arrange these metals in their increasing order of reducing power.