Which of the following repressents correct dissociation of nitrate salts on heating

Options

A. `2LiNO_(3) rarr Li_(2)O + 2NO_(2) + (1)/(2)O_(2)`
B. `Pb(NO_(3))_(2) rarr PbO + 2NO_(2) + (1)/(2) O_(2)`
C. `NH_(4)NO_(3) rarr N_(2)O + 2H_(2)O`
D. `NH_(4)NO_(2) rarr N_(2) + 2H_(2)O`

Answer

To solve the question regarding the correct dissociation of nitrate salts upon heating, we will analyze each of the given nitrate compounds and their expected products when heated.

### Step-by-Step Solution:

1. **Identify the Nitrate Salts**: The question provides four nitrate salts: Lithium Nitrate (LiNO3), Lead Nitrate (Pb(NO3)2), Ammonium Nitrate (NH4NO3), and Ammonium Nitrite (NH4NO2).

2. **Heating Lithium Nitrate (LiNO3)**:
- When lithium nitrate is heated, it decomposes to form lithium oxide (Li2O), nitrogen dioxide (NO2), and oxygen (O2).
- **Equation**: 2 LiNO3 → Li2O + 2 NO2 + O2

3. **Heating Lead Nitrate (Pb(NO3)2)**:
- Upon heating, lead nitrate decomposes to yield lead(II) oxide (PbO), nitrogen dioxide (NO2), and oxygen (O2).
- **Equation**: 2 Pb(NO3)2 → 2 PbO + 4 NO2 + O2

4. **Heating Ammonium Nitrate (NH4NO3)**:
- When ammonium nitrate is heated, it decomposes to produce nitrous oxide (N2O, also known as laughing gas) and water (H2O).
- **Equation**: NH4NO3 → N2O + 2 H2O

5. **Heating Ammonium Nitrite (NH4NO2)**:
- Upon heating, ammonium nitrite decomposes to release nitrogen gas (N2) and water (H2O).
- **Equation**: NH4NO2 → N2 + 2 H2O

6. **Conclusion**: All four nitrate salts dissociate correctly as per the reactions stated above. Therefore, the correct answer is that all options (1, 2, 3, and 4) are correct.

### Final Answer:
All options (1, 2, 3, and 4) represent the correct dissociation of nitrate salts upon heating.

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