In the preparation of `H_(2)SO_(4)`

Options

A. `SO_(2)` is dissolved in `H_(2)SO_(4)`
B. `SO_(2)` is dissolved in water
C. `SO_(3)` is dissolved in conc. `H_(2)SO_(4)`
D. `SO_(3)` is dissolved in dilute `H_(2)SO_(4)`

Answer

To prepare sulfuric acid (H₂SO₄), we can follow these steps:

### Step-by-Step Solution:

1. **Formation of Sulfur Trioxide (SO₃)**:
- The first step involves the reaction of sulfur dioxide (SO₂) with oxygen (O₂) to produce sulfur trioxide (SO₃). This reaction can be represented as:
\[ 2 \text{SO}_2 + \text{O}_2 \rightarrow 2 \text{SO}_3 \]

2. **Dissolution of SO₃**:
- The next step is to dissolve the sulfur trioxide (SO₃) in concentrated sulfuric acid (H₂SO₄). This reaction forms oleum (H₂S₂O₇), which is also known as fuming sulfuric acid. The reaction can be represented as:
\[ \text{SO}_3 + \text{H}_2\text{SO}_4 \rightarrow \text{H}_2\text{S}_2\text{O}_7 \]

3. **Hydration of Oleum**:
- Finally, the oleum (H₂S₂O₇) is then hydrated to produce sulfuric acid (H₂SO₄). This can be represented as:
\[ \text{H}_2\text{S}_2\text{O}_7 + \text{H}_2\text{O} \rightarrow 2 \text{H}_2\text{SO}_4 \]

### Conclusion:
The correct method for the preparation of sulfuric acid (H₂SO₄) involves dissolving sulfur trioxide (SO₃) in concentrated sulfuric acid (H₂SO₄) to form oleum, which is then hydrated to yield sulfuric acid.

### Answer:
The correct option for the preparation of H₂SO₄ is: **SO₃ is dissolved in concentrated H₂SO₄.**

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