When `KMnO_(4)` is reduced with oxalic acid in acidic solution, the oxidation number of `Mn` changes from

Options

A. From ` 7` to `2`
B. From `6` to `2`
C. From `5` to` 2`
D. From `7` to `4`

Answer

A

Explanation

During the reaction of `KMnO_(4)` in acidic medium, following change takes place:
`overset(+7)(M)nO_(4)^(-) rarr overset(+2)(M)n^(2+)`
Thus, the magnitude of change is from `+7` to `+2`