How much is the oxidising power of the `MnO_4^(-) (1M)|Mn^(2+)` (1M) couple decreased if the `H^+` concentration is decreased from 1M to `10^-4 M` at `25^@C`

Explanation

To solve the problem of how much the oxidizing power of the \( \text{MnO}_4^{-} (1M) | \text{Mn}^{2+} (1M) \) couple decreases when the \( \text{H}^{+} \) concentration is decreased from \( 1M \) to \( 10^{-4}M \) at \( 25^{\circ}C \), we can follow these steps:

### Step 1: Write the half-reaction for the reduction of \( \text{MnO}_4^{-} \)
The half-reaction for the reduction of permanganate ion to manganese ion can be written as:
\[ \text{MnO}_4^{-} + 8 \text{H}^{+} + 5 \text{e}^{-} \rightarrow \text{Mn}^{2+} + 4 \text{H}_2\text{O} \]

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