Mention with reason the colour changes observed when :
Silver chloride is exposed to sunlight.

Explanation

**Step-by-Step Solution:**

1. **Identify the Substance:** The substance in question is silver chloride (AgCl), which is initially a white solid.

2. **Exposure to Sunlight:** When silver chloride is exposed to sunlight, it undergoes a chemical reaction known as decomposition.

3. **Chemical Reaction:** The decomposition reaction can be represented as follows:
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