elect the word or phrase that complete each sentence (consti…

elect the word or phrase that complete each sentence (constitutional isomers, diastereomers, enantiomers, meso compounds, primary, secondary, tertiary, higher, lower, reaction, addition, carbocation, carbanion, nucleophiles, electrophiles, elimination, heterolysis, homolysis, reagent, substitution, stronger, weaker, charge, concerted, two step, SN1, SN2, racemization, hyperconjugation, alkyl halides, inversion):     SN2 reactions cannot be performed with ………………….. alkyl halides.  Complete word/phrase and correct spelling (verbatim) is required. No partial credit.