The relative rates of Addition in foll Alkenes are:
  1. (CH3)2--C==C--(CH3)2
  2. CH3--CH2--CH==CH2
  3. CH2==CH2
  4. 4.CH3--CH==CH--CH3
​opt; A. 1>2>3>4 B.1>4>2>3 C.1>4<3>2 D. 1<4<2<3
Ans and Explanation

Dear Student,

The relative rates of addition reaction in alkenes depends upon the stability of carbocation formed. 
Tertiary carbocation > Secondary carbocation > Primary carbocation.

Tertiary carbocation will be formed in (1) as well as (4). However, (1) is more stable than (4) as i (1) two methyl groups are attached to the carbocation formed which due to greater +I effect stabilises the carbocation ore than the carbocation in (4).
So, the order is 1>4
Now, secondary carbocation is formed in case of (2) which is more stable than the primary carbocation formed in (3), but less than the tertiary carbocations formed in (1) and (4).
Therefore, the relative rate of addition reaction is :
B. 1>4>2>3

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