Why Ethene decolourizes `Br_2` solution but ethane does not

Explanation

To understand why ethene decolorizes bromine solution while ethane does not, we need to consider the structural and chemical properties of these two compounds.

### Step-by-Step Solution:

1. **Identify the Compounds**:
- Ethene (C₂H₄) is an alkene, which means it contains a carbon-carbon double bond (C=C).
- Ethane (C₂H₆) is an alkane, which means it contains only single bonds (C-C).

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