Oxidation Number of `Mn` in `[MnO_(4)]^(-)` is:

Options

A. `-7`
B. `+7`
C. `+2`
D. `-2`

Answer

To find the oxidation number of manganese (Mn) in the permanganate ion \([MnO_4]^-\), we can follow these steps:

### Step 1: Identify the oxidation state of oxygen
Oxygen typically has an oxidation state of \(-2\). Since there are four oxygen atoms in the permanganate ion, the total contribution from oxygen will be:
\[ 4 \times (-2) = -8 \]

### Step 2: Set up the equation for the oxidation state of manganese
Let \(X\) represent the oxidation state of manganese (Mn). The overall charge of the permanganate ion is \(-1\). Therefore, we can set up the equation:
\[ X + \text{(total oxidation state from oxygen)} = \text{overall charge} \]
Substituting the values we have:
\[ X - 8 = -1 \]

### Step 3: Solve for \(X\)
Now, we can solve for \(X\):
\[ X - 8 = -1 \\ X = -1 + 8 \\ X = +7 \]

### Conclusion
The oxidation number of manganese (Mn) in the permanganate ion \([MnO_4]^-\) is \(+7\).

### Final Answer
The oxidation number of Mn in \([MnO_4]^-\) is \(+7\).

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