1. The problem statement, all variables and given/known data The decreasing order of rate of SN2 reaction is: a)CH3-Cl b)CH3-CO-CH2-Cl 2. Relevant equations 3. The attempt at a solution I have been trying hard to find the reason why i am wrong. It's obvious that less hindrance, more reactivity towards SN2. Using the same logic, the answer should be a>b but it is b>a. Now i don't understand where i went wrong. There is more hindrance in b than a.