If equal volumes of `0.1 M KMnO_(4)` and `0.1 M K_(2)Cr_(2)O_(7)` solutions are allowed to oxidise `Fe^(2+)` to `Fe^(3+)` in acidic medium, then `Fe^(2+)` oxidised will be:

Options

A. More by `K_(2)Cr_(2)O_(7)`
B. More by `KMnO_(4)`
C. Equal in both cases
D. The data is insufficient to predict the answer

Answer

A

Explanation

`Fe^(2+)toFe^(3+)+1e^(-)`
`MnO_(4)^(ɵ)+8H^(o+)+5e^(-)toMn^(2+)+4H_(2)O`
`Cr_(2)O_(7)^(2-)+14H^(o+)+6e^(-)to2Cr^(3+)+7H_(2)O`
Using mole concept
`1 mol MnO_(4)^(ɵ)-=5 mol Fe^(2+)`
`and 1 mol Cr_(2)O_(7)^(2-)-=6 mol Fe^(2+)`
So, `K_(2)Cr_(2)O_(7)` will oxidise more `Fe^(2+)` to `Fe^(3+)`