nucleophilic substitution

Question 1

sn1 mechanism steps

Answer 1

step 1: leaving group dissociates
step 2: nucleophile attacks

Question 2

what happens to nucleophilicity as you move left to right on the periodic table?

Answer 2

decreases (opposite of acidity trend)

Question 3

what happens to nucleophilicity as you depronate a species?

Answer 3

depronation increases nucleophilicity

Question 4

what happens to nucleophilicity as you move from top to bottom on the periodic table?

Answer 4

depends on solvent.
polar protic: increases top —> bottom
polar aprotic: decreases top —> bottom

Question 5

what happens to nucleophilicity as you increase resonance?

Answer 5

nucleophilicity decreases

Question 6

what happens to electrophilicity as you increase carbocation stability (for sn1)?

Answer 6

reactivity/electrophilicity decreases

Question 7

what makes a better leaving group?

Answer 7

weaker base is better leaving group

Question 8

what reaction mechanism will a tertiary electrophile favour? how about primary?

Answer 8

tertiary: sn1
primary: sn2

Question 9

what conditions will favour an sn2 reaction?

Answer 9

primary (or secondary) electrophile, low steric bulk, strong/anionic nucleophile, polar aprotic solvents

Question 10

what conditions will favour an sn1 reaction?

Answer 10

tertiary electrophile w/ high steric bulk, polar protic solvents