The oxidation state of nitrogen is correctly given for

Options

A. Compound = `[CO(NH_(3))_(5)Cl]Cl_(2)`, Oxidation state = `0`
B. Compound = `NH_(2)OH` , Oxidation state = `-2`
C. Compound =`(N_(2)H_(5))_(2)SO_(4)` , Oxidation state = `+2`
D. Compound = `Mg_(3)N_(2)` , Oxidation state = `-3`

Explanation

To determine the correct oxidation state of nitrogen in the given compounds, we will analyze each option step by step.

### Step 1: Analyze NH3 (Ammonia)
1. **Identify the compound**: NH3
2. **Assign oxidation states**:
- Let the oxidation state of nitrogen be \( x \).
- Each hydrogen has an oxidation state of +1.
- The overall charge of NH3 is 0.
3. **Set up the equation**:
\[ x + 3(+1) = 0 \]
\[ x + 3 = 0 \]
\[ x = -3 \]
4. **Conclusion**: The oxidation state of nitrogen in NH3 is -3.

### Step 2: Analyze NH2OH (Hydroxylamine)
1. **Identify the compound**: NH2OH
2. **Assign oxidation states**:
- Let the oxidation state of nitrogen be \( x \).
- Each hydrogen has an oxidation state of +1, and oxygen has -2.
- The overall charge of NH2OH is 0.
3. **Set up the equation**:
\[ x + 2(+1) + (-2) = 0 \]
\[ x + 2 - 2 = 0 \]
\[ x = 0 \]
4. **Conclusion**: The oxidation state of nitrogen in NH2OH is 0.

### Step 3: Analyze N2H5^2+ (Hydrazinium ion)
1. **Identify the compound**: N2H5^2+
2. **Assign oxidation states**:
- Let the oxidation state of nitrogen be \( x \).
- Each hydrogen has an oxidation state of +1.
- The overall charge of N2H5 is +2.
3. **Set up the equation**:
\[ 2x + 5(+1) = +2 \]
\[ 2x + 5 = 2 \]
\[ 2x = 2 - 5 \]
\[ 2x = -3 \quad \Rightarrow \quad x = -\frac{3}{2} \]
4. **Conclusion**: The oxidation state of nitrogen in N2H5^2+ is -1.5.

### Step 4: Analyze Mg3N2 (Magnesium Nitride)
1. **Identify the compound**: Mg3N2
2. **Assign oxidation states**:
- Let the oxidation state of nitrogen be \( x \).
- Each magnesium has an oxidation state of +2.
- The overall charge of Mg3N2 is 0.
3. **Set up the equation**:
\[ 3(+2) + 2x = 0 \]
\[ 6 + 2x = 0 \]
\[ 2x = -6 \quad \Rightarrow \quad x = -3 \]
4. **Conclusion**: The oxidation state of nitrogen in Mg3N2 is -3.

### Final Conclusion
- The oxidation states of nitrogen in the compounds are:
- NH3: -3
- NH2OH: 0
- N2H5^2+: -1.5
- Mg3N2: -3

The correct oxidation state of nitrogen is given in **Mg3N2**, where it is -3.

### Correct Option
The correct answer is **Mg3N2** (option D), where the oxidation state of nitrogen is correctly given as -3.

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