Concept:In alkynes (like ethyne), the carbon atoms are sp hybridized, featuring linear geometry and a triple bond consisting of one sigma (\( \sigma \)) bond and two pi (\( \pi \)) bonds.
Solution:- Each carbon in ethyne (\( \text{HC}\equiv\text{CH} \)) utilizes sp hybridization.
- The primary sigma bond directly between the two carbon atoms is formed by the head-to-head overlap of an sp orbital from one carbon with an sp orbital from the other carbon.
Why other options are incorrect:- sp-s overlap forms the C-H sigma bonds in ethyne, not the C-C bond.
- \( \text{sp}^2-\text{sp}^2 \) overlap is characteristic of the C-C double bond in alkenes like ethene.
- 2py-2py (and 2pz-2pz) sideways overlaps form the pi (\( \pi \)) bonds, not the sigma bond.
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