Question

The number of moles of `KMnO_(4)` that will be needed to react with one mole of ferrous sulphite in acidic solution is
A. `0.6`
B. `0.4`
C. `0.8`
D. `1.0`

Answer 1

Correct Answer - A
`FeSO_(3) hArr Fe^(2+)+SO_(3)^(2-)`
`MnO_(4)^(-)` oxidises `Fe^(2+)` and `SO_(3)^(2-)` both
`5Fe^(2+)+MnO_(4)^(-)+8H^(+) rarr 5Fe^(3+)+Mn^(2+)+4H_(2)O`
`5SO_(3)^(2-)+2MnO_(4)^(-) rarr 5SO_(4)^(2-)+2Mn^(2+)+H_(2)O`
`5FeSO_(3)+3MnO_(4)^(-) rarr 5Fe^(3+)+5SO_(4)^(2-)+3Mn^(2+)`
`5FeSO_(3)=3MnO_(4)^(-)`
`1FeSO_(3)=(3)/(5)MnO_(4)^(-)=0.6`