Q. The ease of dehydrohalogenation of alkyl halide with alcoholic KOH is
A) 3${^\circ}$<2${^\circ}$<1${^\circ}$
B) 3${^\circ}$>2${^\circ}$>1${^\circ}$
C) 3${^\circ}$<2${^\circ}$>1${^\circ}$
D) 3${^\circ}$>2${^\circ}$<1${^\circ}$
Explanation
(b)
Such dehydrohalogenation follow $E_{2}$ mechanism. The driving force of such reaction is the stability of alkene produced. Since, tertiary alkyl halide can give more substituted alkene, it reacts fastest followed by secondary and primary $i.e.,\ 3{^\circ} > 2{^\circ} > 1{^\circ}.$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.