A metal ion `M^(3+)` after loss of three electrons in a reaction will have an oxidation number equal to

Options

A. zero
B. `+2`
C. `+3`
D. `+6`

Answer

To determine the oxidation number of the metal ion \( M^{3+} \) after it loses three electrons, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Initial Oxidation State**:
The metal ion \( M^{3+} \) has an oxidation state of +3. This is indicated by the charge of the ion.

2. **Understand the Process of Electron Loss**:
When an ion loses electrons, its oxidation state increases. Each electron lost corresponds to an increase of one unit in the oxidation number.

3. **Calculate the Change in Oxidation State**:
Since \( M^{3+} \) loses three electrons, we need to increase the oxidation number by 3.

\[ \text{Initial oxidation state} = +3 \]
\[ \text{Change due to loss of 3 electrons} = +3 \]

4. **Determine the New Oxidation State**:
To find the new oxidation state after losing three electrons, we add the change to the initial oxidation state:

\[ \text{New oxidation state} = +3 + 3 = +6 \]

5. **Conclusion**:
After the loss of three electrons, the oxidation number of the metal ion \( M^{3+} \) becomes +6.

### Final Answer:
The oxidation number after the loss of three electrons is +6.

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