7-Aklyl Halides and Nucleophilic Substitution

Question 1

boiling point of alkyl halides (increase/decrease) as the size of R increases

Answer 1

INCREASE

Question 2

Melting point of alkyl halides (increase/decrease) as the size of R increases

Answer 2

INCREASE

Question 3

Boiling point of alkyl halides (increase/decrease) as the size of
X increases

Answer 3

increase

Question 4

Melting point of alkyl halides (increase/decrease) as the size of X increases

Answer 4

increase

Question 5

alkyl halides are (insoluble/soluble) in organic solvents

Answer 5

soluble

Question 6

alkyl halides are (insolble/insoluble) in water

Answer 6

insoluble

Question 7

alkyl halides undergo ______ reactions with NUCLEOPHILES

Answer 7

substitution

Question 8

alkyl halides undergo ______ reactions with BRONSTED-LOWRY BASES

Answer 8

elimination

Question 9

The better leaving group is the (weaker/stronger) base

Answer 9

weaker

Question 10

across a row, basicity (increases/decreases)

Answer 10

decreases

Question 11

across a row, leaving group ability (increases/decreases)

Answer 11

increases

Question 12

Down a column, basicity (increases/decreases)

Answer 12

decreases

Question 13

Down a column, leaving group ability (increases/decreases)

Answer 13

increases

Question 14

Good leaving groups have (high/low) pKa

Answer 14

low

Question 15

When the leaving group is a weaker base than the nucleophile the (reactants/products) are favored?

Answer 15

products

Question 16

Nucleophiles normally attack?

Answer 16

carbons

Question 17

nucleophilicity (increases/decreases) as basicity (increases/decreases)

Answer 17

increase-increase or decrease-decrease

Question 18

As the number of R groups on the carbon with the leaving group increases, the rate of the SN2 reaction (increases/decreases)

Answer 18

decreases

Question 19

Rate of SN2 reactions (substitution of R group)

Answer 19

(fastest)CH3-X > RCH2-X > R2CH-X > R3C-X (slowest)

Question 20

SN2 Mechanism

kinetics

Answer 20

second order

rate=k[RX][Nu:-]

Question 21

SN2 Mechanism

mechanism

Answer 21

one step

Question 22

SN2 Mechanism

stereochemistry

Answer 22

backside attack of the nucleophile

inversion of configuration at a stereogenic center

Question 23

SN2 Mechanism

identity of R and rate

Answer 23

CH3-X > RCH2X > R2CHX > R3CX

Question 24

SN2 reactions have ___ step(s)

Answer 24

one

Question 25

SN1 reactions have ___ step(s)

Answer 25

two

Question 26

______ are formed as a reactive intermediate in an SN1 reaction

Answer 26

cabocations

Question 27

As the number of R groups on the carbon with the leaving group increases, the rate of the SN1 reaction (increases/decreases)

Answer 27

increases

Question 28

Rate of SN1 reactions (substitution of R group)

Answer 28

(slowest) CH3-X < RCH2-X < R2CH-X < R3C-X(fastest)

Question 29

SN1 Mechanism | kinetics

Answer 29

first order | rate=k[RX]

Question 30

SN1 Mechanism | mechanism

Answer 30

two steps

Question 31

SN1 Mechanism | stereochemistry

Answer 31

trigonal planar carbocation intermediate | racemization at a single stereogenic center

Question 32

SN1 Mechanism | identity of R and rate

Answer 32

R3CX > R2CHX > RCH2X > CH3X

Question 33

carbocation stability

Answer 33

(least stable)CH3 < RCH2 < R2CH < R3C(most stable)

Question 34

Vocab: | spreading our charge by the overlap of an empty p orbital with an adjacent sigma bond is called

Answer 34

hyperconjugation

Question 35

as alkyl substitution increases, dispersal of positive charge (increases/decreases)

Answer 35

increases

Question 36

rate of an SN1 reaction (increases/decreases) as the stability of the carbocation (increases/decreases)

Answer 36

increase-increase or decrease-decrease

Question 37

increasing alkyl substitution favors ___

Answer 37

SN1

Question 38

decreasing alkyl substitution favors ___

Answer 38

SN2

Question 39

strong nucleophiles favor (SN1/SN2)

Answer 39

SN2

Question 40

weak nucleophiles favor (SN1/SN2)

Answer 40

SN1

Question 41

SN1 reactions favor polar (protic/aprotic) solvents

Answer 41

protic

Question 42

SN2 reactions favor polar (protic/aprotic) solvents

Answer 42

aprotic

Question 43

solvent that contains an O-H or N-H bond

Answer 43

polar protic

Question 44

solvent does NOT contain an O-H or N-H bond

Answer 44

polar aprotic