Select the compound(s) having exactly two hybridized carbon atoms in their main chain. — GOC and Organic Chemistry Basics Chemistry Question

💡 Solution & Explanation

But-2-yne ($CH_3-C \equiv C-CH_3$) and pent-1-en-4-yne ($CH_2=CH-CH_2-C \equiv CH$) both contain a single triple bond, which is composed of exactly two $sp$ hybridized carbons. Propa-1,2-diene has only one $sp$ carbon (the central atom).