What happens when `SO_2` reacts with `Cl_2` :
(i) in presence of sunlight.
(ii) in presence of moisture ?

Explanation

To solve the question about the reaction of sulfur dioxide (SO₂) with chlorine (Cl₂) under different conditions, we can break it down into two parts:

### Part (i): Reaction in Presence of Sunlight

1. **Identify the Reactants**: The reactants are sulfur dioxide (SO₂) and chlorine (Cl₂).

2. **Conditions**: The reaction occurs in the presence of sunlight and a catalyst (charcoal).

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