Doubt: I thought that Mg will attack Cl As it is more negetive then Br but it is not [https://learner-dev.s3.ap-south-1.amazonaws.com/1523020814446] why?? Chapter: Haloalkanes and Haloarenes - Subject: Chemistry - Course: NEET Chemistry Course

I thought that Mg will attack Cl As it is more negetive then Br but it is not why??

C-Br bond is easier to break than C-Cl bond which is the first intermediate step in the above reaction.