Oxidation of sulphur dioxide into sulphur trioxide in the absence of a catalyst is a slow process but this oxidation occurs easily in the atmosphere. Explain how does this happen? Give chemical reactions for the conversion of `SO_(2)` into `SO_(3)`.

Explanation

To explain how the oxidation of sulfur dioxide (SO₂) into sulfur trioxide (SO₃) occurs easily in the atmosphere despite being a slow process in the absence of a catalyst, we can break down the explanation into two main methods: photochemical and non-photochemical processes.

### Step-by-Step Solution:

1. **Understanding the Reaction**:
- The oxidation of sulfur dioxide (SO₂) to sulfur trioxide (SO₃) can be represented by the following chemical equation:
\[
2 \, \text{SO}_2 + \text{O}_2 \rightarrow 2 \, \text{SO}_3
...