How many moles of acidified permanganate are required to oxidise one mole of ferrous oxalate? 

Explanation

Ferrous oxalate `FeC_(2)O_(4)` is a dual reductant
`Fe^(2+) overset(1e^(-))to Fe^(3+)`
`C_(2)O_(4)^(2-) overset(2e^(-))to 2CO_(2)`
One mole of `Fe_(2)C_(2)O_(4)` is involved in 3 electron change.
`MnO_(4)^(2-) overset(5e^(-))to Mn^(2+)`
One mole of `MnO_(4)^(-)` in acid medium is involved in 5 electron change
5 moles of `FeC_(2)O_(4)=3" moles of "MnO_(4)^(-)`
1 moles of `FeC_(2)O_(4)=?`
Number of moles of permanganate that can be oxidised by one mole of ferrous oxalate `=3/5 xx 1=0.6`