Rate of reaction with HBr [closed]








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Rate of reaction is more when Carbon is more electrophile(less electron density)


So according to me the order should be D>B>C>A


As NO2 has -M -I effect , Cl has +M -I effect , while OCH3 has +M -I effect.


But the answer given as A>B>C>D




Stability of carbocation is directly proportional to +M effect .
So ,
 carbocation will more stable on A then on B and then C as NO2 has high -M. Effect it's last..


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