Question

Which among the following molecules has the shortest $CH$ bond length?

• A. Ethane
• B. Ethene
• C. Ethyne
• D. All of the above have equal $CH$ bond lengths

Answer 1

The correct option is C Ethyne

Greater the $s-$ character, shorter the bond length. Hence, ethane with $s{p}^3$ hybridization has the longest bond length and ethyne with $sp$ hybridization has the shortest bond length.