What order or C-H bond lengths do you expect in `C_(2) H_(6), C_(2) H_(4) and C_(2) H_(2)` and why ?

Explanation

To determine the order of C-H bond lengths in the molecules C₂H₆ (ethane), C₂H₄ (ethene), and C₂H₂ (ethyne), we need to analyze the type of bonds present in each molecule and how bond order affects bond length.

### Step-by-Step Solution:

1. **Identify the Types of Bonds:**
- **C₂H₆ (Ethane)**: This molecule has single C-H bonds. Each carbon atom is bonded to three hydrogen atoms through single bonds.
- **C₂H₄ (Ethene)**: This molecule has double C-H bonds. Each carbon atom is bonded to two hydrogen atoms and has a double bond with the other carbon atom.
- **C₂H₂ (Ethyne)**: This molecule has triple C-H bonds. Each carbon atom is bonded to one hydrogen atom and has a triple bond with the other carbon atom.
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