Chemistry - Electrochemistry Question with Solution | TestHub

$\begin{array}{rl}& {\mathrm{E}}_{{\mathrm{Cr}}_2{\mathrm{Of}}_4^{\circ }/{\mathrm{ca}}^8}^0=1.33{\mathrm{V}}_{{\mathrm{C}}_2/\mathrm{Cr}}^{\circ }=1.36\mathrm{V}\\ & {\mathrm{E}}_{{\mathrm{MnO}}_4/{\mathrm{Mm}}^2}^{\circ }=1.51\mathrm{V}{\mathrm{E}}_{{\mathrm{Cr}}^2/\mathrm{Cr}}^0=-0.74\mathrm{V}\end{array}$
The species which has the most negative value of standard reduction potential will be the strongest reducing agent. Since ${\mathrm{Cr}}^{3+}/\mathrm{Cr}$ has SRP value of $-0.74\mathrm{V},\mathrm{Cr}$ is the strongest reducing agent.