Question

`KMnO_(4)` acts as an oxidizing agent in acidic medium. The number of moles of `KMnO_(4)` that will be needed to react with one mole of sulphide ions in acidic solution is
A. `(2)/(5)`
B. `(3)/(5)`
C. `(4)/(5)`
D. `(1)/(5)`

Answer 1

Correct Answer - a
`2KMnO_(4)+ 3H_(2)SO_(4) rarr K_(2)SO_(4) + 2MnSO_(4) + 3H_(2)O + 5(O)`
`H_(2)S+ (O) rarr H_(2)OI +S ] xx 5`
`bar ( 2KMnO_(4) + 3H_(2)SO_(4) + 5H_(2)Srarr K_(2)SO_(4) + 8 H_(2)O 5S)`
1 mole of `S^(2-)` ions will required`KMnO_(4) = ( 2)/( 5) `moles