In the reactant of KMnO₄ with an oxalate in acidic medium. ${\mathrm{MnO}}_4^{-}$ is reduced to ${\mathrm{Mn}}^{2+}$ and ${\mathrm{C}}_2{\mathrm{O}}_4^{2-}$is oxidized to CO₂. Hence, 50ml of 0.02 M KMnO₄ is equivalent to