Question

Question 25
Which of the following does not belong to the same homologous series?
(a) ${\text{CH}}_4$
(b) ${\text{C}}_2{\text{H}}_6$
(c) ${\text{C}}_3{\text{H}}_8$
(d) ${\text{C}}_4{\text{H}}_8$

Answer 1

The answer is (d) ${\text{C}}_4{\text{H}}_8$.

A homologous series is a series of compounds with the same general formula, usually varying by a ${\text{CH}}_2$ group. In the given list of compounds methane, ethane and propane belong to the same homologous series of compounds and butene does not.