Give reasons for
Methane does not undergo addition reactions, but ethene does.

Explanation

To understand why methane does not undergo addition reactions while ethene does, we need to look at the structure and bonding of both molecules.

### Step-by-Step Solution:

1. **Identify the Structures**:
- Methane (CH₄) consists of one carbon atom bonded to four hydrogen atoms. Its structure is tetrahedral, and it has only single bonds (sigma bonds).
- Ethene (C₂H₄) consists of two carbon atoms, each bonded to two hydrogen atoms, and has a double bond (one sigma bond and one pi bond) between the two carbon atoms.

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