Which of the following pairs of hydrocarbons correctly represent the stated type of structural isome — Hydrocarbons Chemistry Question

💡 Solution & Explanation

(A) Chain isomers have the same formula but a different carbon skeleton; 1-butene is straight, 2-methylprop-1-ene is branched. (B) Position isomers differ only in the location of the functional group/double bond. (C) Propyne has a triple bond (alkyne), while allene has two double bonds (alkadiene); they have different functional groups but the same formula ($C_3H_4$), making them functional isomers. (D) is incorrect because an open chain alkene and a cycloalkane represent ring-chain isomerism, not simple chain isomerism.