12 litre of `H_2` and 11.2 litre of `Cl_2` are mixed and exploded. The composition by volume of mixture is:

Explanation

To solve the problem, we need to determine the composition by volume of the mixture after the reaction between hydrogen (H₂) and chlorine (Cl₂) gases. The balanced chemical equation for the reaction is:

\[ \text{H}_2(g) + \text{Cl}_2(g) \rightarrow 2 \text{HCl}(g) \]

### Step-by-Step Solution:

1. **Identify the volumes of reactants:**
- Volume of H₂ = 12 liters
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