Question

Arrange the following alkyl halides in decreasing order of the rate of $\beta$-elimination reaction with alcoholic $KOH$

• A. $a>c>b$
  
• B. $b>c>a$
  
• C. $c>b>a$
  
• D. $a>b>c$
  

Answer 1

The correct option is A $a>c>b$


Alkyl halides on heating with alcoholic potash eliminates one molecule of halogen acid to form an alkene.
a)

b)
So, the alkyl halide which produces the most stable alkene will have maximum reactivity.

Hence, the order of reactivity for $\beta$-elimination


Hence, the correct option is (D).