Which oxide of nitrogen is used as a catalyst in lead chamber process for the manufacture of `H_2SO_4`?

Options

A. `NO`
B. `NO_(2)`
C. `N_(2)O_(4)`
D. `N_(2)O_(5)`

Explanation

To solve the question "Which oxide of nitrogen is used as a catalyst in the lead chamber process for the manufacture of H₂SO₄?", we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Lead Chamber Process**:
- The lead chamber process is a method used to produce sulfuric acid (H₂SO₄) by oxidizing sulfur dioxide (SO₂) in the presence of nitrogen oxides.

2. **Identify the Role of Nitrogen Oxides**:
- In this process, nitrogen oxides act as catalysts. A catalyst is a substance that increases the rate of a chemical reaction without being consumed in the process.

3. **Determine the Specific Nitrogen Oxide Used**:
- The nitrogen oxide that is commonly used as a catalyst in the lead chamber process is nitric oxide (NO).

4. **Write the Reaction Equation**:
- The overall reaction in the lead chamber process can be represented as:
\[ 2 \text{SO}_2 + \text{O}_2 + \text{NO} \rightarrow 2 \text{SO}_3 \]
- Here, sulfur dioxide (SO₂) reacts with oxygen (O₂) in the presence of nitric oxide (NO) to produce sulfur trioxide (SO₃).

5. **Conclude the Answer**:
- Therefore, the oxide of nitrogen used as a catalyst in the lead chamber process for the manufacture of H₂SO₄ is nitric oxide (NO).

### Final Answer:
The oxide of nitrogen used as a catalyst in the lead chamber process for the manufacture of H₂SO₄ is **NO (Nitric Oxide)**.

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