Q. Which of the following alkenes is most reactive towards cationic polymerization?
A) ${CH}_{2} = \ {CHCH}_{3}$
B) $H_{2}C\ = \ CHCl$
C) $H_{2}C = {CHC}_{6}H_{5}$
D) $H_{2}C\ = \ {CHCO}_{2}{CH}_{3}$
Explanation
(c)
In cationic polymerization,carbocationsare formed. Greater the stability of the carbocation, more reactive is the alkene. Since, the stability of the intermediate carbocation follows the order.
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Therefore, reactivity decreases in the same order. Thus, styrene is most reactive.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.