Nitrogen dioxide can not be obtained from

Options

A. `Cu(NO_(3))_(2)`
B. `Hg(NO_(3))_(2)`
C. `NaNO_(3)`
D. `AgNO_(3)`

Explanation

To determine which reactant does not produce nitrogen dioxide (NO2), we will analyze the decomposition reactions of each compound mentioned in the question.

### Step-by-Step Solution:

1. **Analyze Copper Nitrate (Cu(NO3)2)**:
- When copper nitrate is heated, it decomposes according to the reaction:
\[ \text{Cu(NO}_3\text{)}_2 \rightarrow \text{CuO} + 2\text{NO}_2 + \frac{1}{2}\text{O}_2 \]
- **Conclusion**: Copper nitrate produces nitrogen dioxide (NO2).

2. **Analyze Mercuric Nitrate (Hg(NO3)2)**:
- When mercuric nitrate is heated, it decomposes as follows:
\[ \text{Hg(NO}_3\text{)}_2 \rightarrow \text{Hg} + 2\text{NO}_2 + \text{O}_2 \]
- **Conclusion**: Mercuric nitrate also produces nitrogen dioxide (NO2).

3. **Analyze Sodium Nitrate (NaNO3)**:
- When sodium nitrate is heated, it decomposes to form:
\[ 2\text{NaNO}_3 \rightarrow 2\text{NaNO}_2 + \frac{1}{2}\text{O}_2 \]
- **Conclusion**: Sodium nitrate does not produce nitrogen dioxide (NO2).

4. **Analyze Silver Nitrate (AgNO3)**:
- When silver nitrate is heated, it decomposes according to the reaction:
\[ 2\text{AgNO}_3 \rightarrow 2\text{Ag} + 2\text{NO}_2 + \text{O}_2 \]
- **Conclusion**: Silver nitrate produces nitrogen dioxide (NO2).

### Final Conclusion:
Among the four compounds analyzed, only sodium nitrate does not yield nitrogen dioxide as a product upon decomposition. Therefore, the answer is:

**Sodium Nitrate (NaNO3)** cannot be obtained from nitrogen dioxide.

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