- SN2 reaction rate is influenced by the leaving group; a superior leaving group results in a faster SN2 substitution. - Iodine (I\(^-\)) functions as a superior leaving group compared to bromine (Br\(^-\)), attributable to iodine's larger atomic size and the weaker bond it forms with the carbon atom.- Consequently, ethyl iodide (CH\(_3\)CH\(_2\)I) will experience a faster SN2 reaction than ethyl bromide (CH\(_3\)CH\(_2\)Br). \\end{center}