The compound that does not produce nitrogen gas by the thermal decomposition is

Options

A. `NH_4 NO_2`
B. `(NH_4)_2 SO_4`
C. `Ba(N_3)_2`
D. `(NH_4)_2 Cr_2 O_7`

Explanation

To determine the compound that does not produce nitrogen gas (N2) upon thermal decomposition, we will analyze the thermal decomposition reactions of the given compounds.

### Step-by-Step Solution:

1. **Identify the Compounds**: We need to analyze the thermal decomposition of the following compounds:
- NH4NO2 (Ammonium nitrite)
- NH4SO4 (Ammonium sulfate)
- N3 (Azide)
- NH4Cr2O7 (Ammonium dichromate)

2. **Thermal Decomposition of NH4NO2**:
- When ammonium nitrite (NH4NO2) is heated, it decomposes to produce nitrogen gas (N2) and water (H2O).
- Reaction:
\[ 2 NH4NO2 \rightarrow N2 + 4 H2O \]
- **Conclusion**: N2 is produced.

3. **Thermal Decomposition of NH4SO4**:
- When ammonium sulfate (NH4)2SO4 is heated, it decomposes to produce ammonia (NH3) and sulfuric acid (H2SO4).
- Reaction:
\[ (NH4)2SO4 \rightarrow 2 NH3 + H2SO4 \]
- **Conclusion**: N2 is not produced.

4. **Thermal Decomposition of N3**:
- When azide (N3) is heated, it decomposes to produce nitrogen gas (N2).
- Reaction:
\[ 2 N3 \rightarrow 3 N2 \]
- **Conclusion**: N2 is produced.

5. **Thermal Decomposition of NH4Cr2O7**:
- When ammonium dichromate (NH4)2Cr2O7 is heated, it decomposes to produce nitrogen gas (N2) and chromium(III) oxide (Cr2O3).
- Reaction:
\[ (NH4)2Cr2O7 \rightarrow N2 + Cr2O3 + 4 H2O \]
- **Conclusion**: N2 is produced.

### Final Answer:
The compound that does not produce nitrogen gas by thermal decomposition is **(NH4)2SO4 (Ammonium sulfate)**.

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