In order of oxidise a mixture containing one mole of each of `FeC_(2)O_(4).FeSO_(4)` and `Fe(NO_(2))_(3)` is acidic medium, the number of moles of `KMnO_(4)` required is

Answer

`2`

Explanation

(i) `FEC_(2)O_(4)-=Fe^(2+)+C_(2)O_(4)^(2-)`
5 moles of `C_(2)O_(4)^(2-)` react with 2 moles of acidified `KMnO_(4)`
1 mole of `c_(2)` of `2/4` react with `2/5` moles of `KMnO_(4)` Also 5 moles of `Fe^(2+)` react with 1 mole of `Fe^(2+)` reacts with `1/5` moles of `KMnO_(4)`. Total moles of `KMnO_(4)` required for 1 mole of `FeC_(2)O(4)=2/5+1/5=3/5`
(ii) `FeSO_(4)=Fe^(2+)+SO_(4)^(2-)`
5 moles of `Fe^(2+)` react with 1 mole of acidified `KMnO_(4)`
1 mole of `Fe^(2+)` reacts with `1/5` moles of `KMnO_(4)SO_(4)^(2-)` is not affected by `KMnO_(4)` Total moles of `KMnO_(4)` required for 1 mole of `FESO_(4)=1/5`
(iii) `Fe(NO_(2))_(3)-=Fe^(3+)+3NO_(2)`
5 moles of `NO_(2)^(-)` react with 2 moles of acidified `KMnO_(4)`
3 moles of `NO_(2)^(-)` reat with `6/5` moles of
`KMnO_(4)Fe^(3+)` is not affected by `KMnO_(4)`
`:.` Total moles of `KMnO_(4)` required for 1 mole of `Fe(NO_(2))_(3)=6/5` Total moles required `=3/5+1/5+6/5=2`