Concept:An \( \text{sp}^3 \) hybridized carbon atom must be attached to four separate domains exclusively by single bonds (sigma bonds).
Formula:$$ \text{sp}^3 \implies \text{Only single bonds (alkane-like carbons)} $$
Solution:- Benzene (\( \text{C}_6\text{H}_6 \)) consists of a planar hexagonal ring where every single carbon atom forms one double bond (delocalized) and two single bonds. Therefore, every carbon in benzene is \( \text{sp}^2 \) hybridized. It has absolutely zero \( \text{sp}^3 \) carbons.
- 1-Butene, 2-Butyne, and 1-Pentene all contain carbon chains that feature standard alkane-like \( \text{CH}_2 \) or \( \text{CH}_3 \) groups, which are fully \( \text{sp}^3 \) hybridized.
Why other options are incorrect:- Option B, Option C, Option D: These aliphatic chains contain at least one saturated carbon with four single bonds, meaning they do possess \( \text{sp}^3 \) hybridized carbons.
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