During SN2 mechanism of alkyl halides C- X bond undergoes:

Explanation

In the SN2 (substitution nucleophilic bimolecular) mechanism of alkyl halides, the carbon-halogen (C-X) bond undergoes heterolytic cleavage, not homolytic cleavage. The nucleophile attacks the substrate, leading to a concerted reaction where a new bond is formed between the nucleophile and the carbon while the bond between the carbon and the leaving group (X) breaks with both electrons going to the leaving group. This results in the formation of a new C-Nucleophile bond and the departure of the leaving group. The process involves a transition state where the nucleophile and the leaving group are both partially bonded to the carbon atom.