(a) Draw the structure of major monohalo products in each of the reaction. (refer diagram) (b) Which halogen compound in each of the following pairs will react faster in SN2 reaction: (i) CH3Br or CH3I (ii) (CH3)3C-Cl or CH3-Cl

(b)(i) CH3I will react faster in SN2 reaction than CH3Br. This is because I⁻ is a better leaving group, owing to its greater size than Br⁻. As a result, it will leave at a faster rate in the presence of an incoming nucleophile. (ii) CH3Cl will react faster in SN2 reaction than (CH3)3-Cl, as CH3-Cl is a primary halide whereas (CH3)3C-Cl is a tertiary halide. Primary halides undergo SN2 reactions faster.