How many moles of `KMnO_(4)` are required to oxidise one mole of ferrous oxalate in acidic medium ?

Explanation

Ferrous oxalate is dual reducing agent. In acidic medium `MnO_(4)^(-)` oxidies ferrous ion to ferric ion and oxalate ion to `CO_2` . Thus balanced equation for the reaction between the permanganate ion and ferrous oxalate is `3MnO_4^(-)("3 mole") + 5FeC_2O_4("5 mole ") + 24 H^+ rarr 3Mn^(2+) + 5Fe^(3+) + 10CO_2 + 12H_2O`
Thus one mole of `KMnO_4` can oxidise 1.67 moles of ferrous oxalate.