Balance the following reaction by the oxidation number method -
`MnO_(4)^(-)+Fe^(+2)rarrMn^(+2)+Fe^(+3)`

Explanation

To balance the reaction \( \text{MnO}_4^{-} + \text{Fe}^{2+} \rightarrow \text{Mn}^{2+} + \text{Fe}^{3+} \) using the oxidation number method, we can follow these steps:

### Step 1: Assign Oxidation Numbers
- For \( \text{MnO}_4^{-} \):
- Let the oxidation number of Mn be \( x \).
- The oxidation number of O is \(-2\).
- The equation becomes: \( x + 4(-2) = -1 \)
- Solving gives \( x - 8 = -1 \) → \( x = +7 \).
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