If equal volumes of 0.1 M ${\mathrm{KMnO}}_4^{ }$and 0.1 M ${\mathrm{K}}_2{\mathrm{Cr}}_2{\mathrm{O}}_7$ solutions are allowed to oxidize ${\mathrm{Fe}}^{2+} \mathrm{to} {\mathrm{Fe}}^{3+}$ in acidic medium, then ${\mathrm{Fe}}^{2+}$ oxidized will be

${\mathrm{K}}_2{\mathrm{Cr}}_2{\mathrm{O}}_7$ has greater n factor as compared to ${\mathrm{KMnO}}_4^{ }$, so same volume of ${\mathrm{K}}_2{\mathrm{Cr}}_2{\mathrm{O}}_7$ will oxidize more amount of ${\mathrm{Fe}}^{2+}$

$$\begin{gathered} \stackrel{+7}{\mathrm{Mn}}{\mathrm{O}}_4^{-}\to {\mathrm{Mn}}^{+2} (\mathrm{n}-\mathrm{factor}=5) \\ {\stackrel{+6}{\mathrm{Cr}}}_2{\mathrm{O}}_7^{-2}\to 2{\mathrm{Cr}}^{+3} (\mathrm{n}-\mathrm{factor}=6) \end{gathered}$$