The gas obtained on heating lead nitrate to `400^(@) C` :

Options

A. `N_(2)O`
B. `NO`
C. `NO_(2)`
D. `N_(2)O_(5)`

Answer

To determine the gas obtained on heating lead nitrate (Pb(NO3)2) to 400°C, we can follow these steps:

### Step 1: Identify the chemical formula of lead nitrate
Lead nitrate is represented by the chemical formula Pb(NO3)2.

### Step 2: Understand the decomposition reaction
When lead nitrate is heated, it undergoes thermal decomposition. This means that it breaks down into simpler substances when exposed to heat.

### Step 3: Write the decomposition reaction
The decomposition of lead nitrate can be represented by the following chemical equation:
\[ 2 \text{Pb(NO}_3\text{)}_2 \rightarrow 2 \text{PbO} + 4 \text{NO}_2 + \text{O}_2 \]
This equation shows that lead nitrate decomposes to form lead oxide (PbO), nitrogen dioxide (NO2), and oxygen (O2).

### Step 4: Identify the gases produced
From the decomposition reaction, we can see that two gases are produced:
1. Nitrogen dioxide (NO2)
2. Oxygen (O2)

### Step 5: Determine the primary gas of interest
Since the question specifically asks for the gas obtained, we can focus on nitrogen dioxide (NO2), which is typically the gas of interest in this reaction.

### Conclusion
The gas obtained on heating lead nitrate to 400°C is nitrogen dioxide (NO2).

### Final Answer
The correct answer is NO2.

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