`SO_2` acts as a bleaching agent. How?

Explanation

To understand how sulfur dioxide (SO₂) acts as a bleaching agent, we can break down the process step by step.

### Step 1: Formation of Sulfuric Acid
When sulfur dioxide is introduced to moisture (water), it reacts to form sulfuric acid (H₂SO₄). The chemical reaction can be represented as follows:

\[ SO_2 + H_2O \rightarrow H_2SO_4 \]
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