ochem ch 6 alkyl halides part 3

increases, because of size and polarizability increase

weak

• reduce the strength of the nucleophile (which
• makes it more favorable for Sn1 and less favorable for Sn2). The hydrogen bonds
• between the solvent and the nucleophile must be broken before the nucleophile
• can attack the carbon

• do not form hydrogen bonds with the nucleophile.
• Favors Sn2 reactions and disfavors sn1 reactions

• inversion doesn't always result in a change i
• nthe configuration of the chiral carbon, but 99% of the time it does.

yes

rate = k[R-X]

• so, concentration of nucleophile doesn't play a role in the rate, only the
• concentration of the alkyl halide does.

tertiary>secondary>primary>>>methyl

weak

unimolecular (meaning only one molecule is involved in the transition stat eof the rate limiting step) nucleophilic substitution. it is a multi-step reaction (2-3 steps) that involves a carbocation intermediate. 

Ex. 

• Step 1 formation of carbocation (slow step)
• 

• Step 2 nucleophilic attack
• 

• Step 3 Loss of Hydrogen ion (H+) if needed
• 

there is only one molecule involved in the transition state of the rate-limiting step