Chemistry - Electrochemistry Question with Solution | TestHub

The standard reduction potentials at $298\mathrm{K}$ for the following half cells are given below : $\begin{array}{l}{\mathrm{Cr}}_2{\mathrm{O}}_7^{2-}+14{\mathrm{H}}^{+}+6{\mathrm{e}}^{-}\to 2{\mathrm{Cr}}^{3+}+7{\mathrm{H}}_2\mathrm{O},{\mathrm{E}}^{\circ }=1.33\mathrm{V}\\ {\mathrm{Fe}}^{3+}(\mathrm{aq})+3{\mathrm{e}}^{-}\to \mathrm{Fe}{\mathrm{E}}^{\circ }=-0.04\mathrm{V}\\ {\mathrm{Ni}}^{2+}(\mathrm{aq})+2{\mathrm{e}}^{-}\to \mathrm{Ni}{\mathrm{E}}^{\circ }=-0.25\mathrm{V}\\ {\mathrm{Ag}}^{+}(\mathrm{aq})+{\mathrm{e}}^{-}\to \mathrm{Ag}{\mathrm{E}}^{\circ }=0.80\mathrm{V}\\ {\mathrm{Au}}^{3+}(\mathrm{aq})+3{\mathrm{e}}^{-}\to \mathrm{Au}{\mathrm{E}}^{\circ }=1.40\mathrm{V}\end{array}$ Consider the given electrochemical reactions, The number of metal(s) which will be oxidized be ${\mathrm{Cr}}_2{\mathrm{O}}_7^{2-}$, in aqueous solution is ______