Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Chemistry 101 COPY > Substitution Reactions (SN2) > Flashcards

Substitution Reactions (SN2) Flashcards

1
Q

Which is the better leaving group: H2O or I-?

A

H2O

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Which is the better nucleophile: CH3CO2- or F-?

A

F-

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Which is the better leaving group: Br- or I-?

A

I-

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Which is the better leaving group: OR- or F-?

A

F-

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How many transition states does a concerted mechanism have?

A

One

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Why can’t substitution reactions occur in vinylic alkyl halides?

A

The bonds are too strong

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Is a concerted substitution reaction bimolecular or unimolecular?

A

Bimolecular

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are concerted substitution reactions also called?

A

SN2 reactions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

For a concerted substitution reaction, what is the order of reaction speed by the order of the halide?

A

Primary>Secondary>Tertiary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Why do primary alkyl halides react fastest in concerted substirution reactions?

A

As there is the least steric hindrance and thus most room for the nucleophile to attack

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the worst leaving group?

A

OH-

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How does an SN2 reaction get its name?

A

Substitution Nucleophilic Bimolecular (2)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Which is the better leaving group: Br- or I-?

A

Br-

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Which is the better leaving group: CH3CO2- or Cl-?

A

Cl-

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the easiest way to identify the spectator ion?

A

They are always a group I or II atom.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What may be the result of the nucleophile attacking from the opposite side to the leaving group in a concerted substitution reaction?

A

The orientation of the molecule may change.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How many arrows are shown in a substitution reaction?

A

Two

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the three steps for showing the mechanism of stepwise substitution reactions?

A

Identify the nucleophile, leaving group, δ+ carbon and the spectator ion

Draw the arrows for the first step (leaving group stealing e-)

Draw the arrows for the second step showing the carbocation and then an arrow to show the nucleophile attacking the positive charge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is a concerted process (in terms of a substitution reaction)?

A

Where nucleophilic attack and the loss of leaving group occur simultaneously

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Which is the better leaving group: CH3CO2- or F-?

A

CH3CO2-

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

How many transition states does a stepwise mechanism have?

A

Two

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

How many “steps” are shown in a concerted substitution reaction?

A

One

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Can concerted substitution reactions occur in aryl halides?

A

No

24
Q

What is the rate law for a concerted substitution reaction?

A

Rate = k[alkyl halide][nucleophile]

25
Q

What is the best nucleophile?

A

OH-

26
Q

Which is the better nucleophile: CH3CO2- or Cl-?

A

CH3CO2-

27
Q

State the molecular geometry of the molecule in concerted substitution reaction by step

A

Tetrahedral to start Planar in transition state Tetrahedral to finish (inverted if chiral)

28
Q

What are the two steps for showing the mechanism of concerted substitution reactions?

A

Identify the nucleophile, leaving group, δ+ carbon and the spectator ion Draw arrows (nuc→δ+ carbon) and (leaving group stealing e-)

29
Q

How can you make the rate of reaction faster?

A

Lower the energy of the transition state, hence lowering the activation energy

30
Q

What are the two arrows shown in a substitution reaction?

A

One for the loss of a leaving group One for the nucleophilic attack

31
Q

What is the relationship between how good of a nucleophile and how good of a leaving group an ion is?

A

The better the leaving group, the worse the nucleophile, or vice versa

32
Q

Which is the better leaving group: Br- or Cl-?

A

Br-

33
Q

What is the easiest way to determine which atom is the most electronegative (usually)?

A

The atom with the negative charge

34
Q

Which is the better leaving group: Br- or I-?

A

<span>I</span>-

35
Q

Can concerted substitution reactions occur in vinylic alkyl halides?

A

No

36
Q

Which is the better nucleophile: OR- or NH2-?

A

NH2-

37
Q

Which is the better nucleophile: OH- or NH2-?

A

OH-

38
Q

How is the nucleophile able to attack the alkyl halide?

A

Using its lone pair

39
Q

Do concerted mechanisms and stepwise mechanisms have a different number of steps?

A

No. They just occur at different times.

40
Q

What does the rate of reaction ultimately depend on?

A

How stable the transition state is

41
Q

Which is the better leaving group: OR- or NH2-?

A

OR-

42
Q

What is a stepwise process (in terms of a substitution reaction)?

A

Where the loss of leaving occurs first, followed by nucleophilic attack

43
Q

How does the strength of a base relate to the stability of the anion?

A

Strong bases = unstable anions

44
Q

What charge will the leaving group always have?

A

A delta negative charge

45
Q

How many “steps” are shown in a stepwise substitution reaction?

A

Two

46
Q

Which is the better nucleophile: OR- or F-?

A

OR-

47
Q

Which is the better leaving group: OH- or NH2-?

A

NH2-

48
Q

What side does the nucleophile attack from in a concerted substitution reaction?

A

From the opposite side to the leaving group

49
Q

Which is the better leaving group: H2O or I-?

A

H2O

50
Q

What is the best leaving group?

A

H2O

51
Q

Do stepwise and concerted reactions have the same products?

A

No.

52
Q

What is the worst nucleophile?

A

H2O

53
Q

Why can’t substitution reactions occur in aryl halides?

A

The geometry of the molecule prevents the backside attack from the nucleophile

54
Q

How do acidity and basicity relate to the quality of a leaving group or nucleophile?

A

The stronger the base, the better the nucleophile

The stronger the acid, the better the leaving group

55
Q

How does electronegativity relate to the quality of a leaving group and a nucleophile?

A

The higher the electronegativity, the better the nucleophile

The lower the electronegativity, the better the leaving group

Chemistry 101 COPY (32 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions