Delgado Community College CHEM 222 Chapter 6

Delgado Community College

CHEM 222

Chapter 6.Ionic Reactions

Multiple Choice

Section: 6.3

1)Which is the best nucleophile?

1. C^-
2. N^-
3. O^-
4. F^-

Section: 6.4

2. The best leaving group produces a                                           base that is a(n)                                  

anion.

1. weak, stable
2. strong, stable
3. weak, unstable
4. strong, unstable

Section: 6.4

3. Which is the best leaving group?

1. Br^-
2. Cl^-
3. F^-
4. I^-

Section: 6.5

4. S_N2 reactions are                                 and have                              kinetics.

1. unimolecular, 2^nd order
2. unimolecular, 1^st order
3. bimolecular, 2^nd order
4. bimolecular, 1^st order

Section: 6.5

5. In an S_N2 reaction, if the [nucleophile] doubles, the reaction rate                                             . In an S_N2 reaction, if the [substrate] doubles, the reaction rate                                                                                .

1. doubles, doubles
2. halves, halves
3. doubles, halves
4. halves, doubles
5. doubles, will not be effected
6. will not be effected, doubles

Section: 6.8

6. S_N2 reactions proceed with a(n)                                     of configuration.

1. inversion
2. retention
3. racemization

Section: 6.9

7. S_N1 reactions are                                 and have                              kinetics.

1. unimolecular, 2^nd order
2. unimolecular, 1^st order
3. bimolecular, 2^nd order
4. bimolecular, 1^st order

Section: 6.9

8. In an S_N1 reaction, if the [nucleophile] doubles, the reaction rate                                             . In an S_N1 reaction, if the [substrate] doubles, the reaction rate                                                                                .

1. doubles, doubles
2. halves, halves
3. doubles, halves
4. halves, doubles
5. doubles, will not be effected
6. will not be effected, doubles

Section: 6.6, 6.10

9. The S_N2 mechanism is characterized by the presence of a(n)                                              . The S_N1 mechanism is characterized by the formation of a(n)                                                                                     called a(n)

                        .

1. intermediate, transition state, carbocation
2. transition state, intermediate, carbanion
3. intermediate, intermediate, carbanion
4. transition state, intermediate, carbocation
5. transition state, transition state, carbocation

Section: 6.10

10. Which mechanism(s) is represented by the following?

1. S_N1
2. S_N2
3. E1
4. E2
5. S_N1 solvolysis
6. a and c
7. b and d
8. a, c and e

Section: 6.11

11. The order for stability of carbocations is                                             .

1. methyl > tertiary > secondary > primary
2. methyl > primary > secondary > tertiary
3. tertiary > secondary > primary > methyl
4. secondary > tertiary > primary > methyl

Section: 6.11

12. Carbocations have                                        geometry.

1. tetrahedral
2. octahedral
3. bent
4. linear
5. trigonal pyramidal
6. trigonal planar

Section: 6.12

13. S_N1 reactions produce                                   products.

1. inverted
2. identical
3. racemic

Section: 6.13

14. In an S_N2 reaction, reaction rates are affected by the                                                  of the substrate. In an S_N1 reaction, reaction rates are determined by the                                                                                                  of the carbocation.

1. stability, substrate
2. steric hindrance, stability
3. substrate, concentration
4. stability, steric hindrance

Section: 6.13

15. S_N1 reactions run best in                                         solvents and S_N2 reactions run best in

                            solvents.

1. polar protic, polar protic
2. polar protic, polar aprotic
3. polar aprotic, polar aprotic
4. polar aprotic, polar protic

Section: 6.13

16. 
    Which of the following is a polar protic solvent?

1. I
2. II
3. III
4. IV
5. I and IV
6. I, II and IV
7. all of the above

Section: 6.6, 6.7, 6.16

17. Which mechanism(s) is represented by the following?

1. S_N1
2. S_N2
3. E1
4. E2
5. S_N1 solvolysis
6. a and c
7. b and d
8. a, c and e

Section: 6.10, 6.17

18. Which mechanism(s) is represented by the following?

1. S_N1
2. S_N2
3. E1
4. E2
5. S_N1 solvolysis
6. a and c
7. b and d
8. a, c and e

Section: 6.18

19.                                increases the likelihood of elimination occurring instead of substitution.

1. Increased pressure
2. Increased temperature
3. Decreased pressure
4. Decreased temperature

Section: 6.13, 6.18, 6.19

20. S_N2 reactions proceed fastest with                                      substrates.

1. Primary
2. Secondary
3. Tertiary

Section: 6.18, 6.19

21. Primary substrates always give S_N2 reactions with all bases except for

                        , which will give E2 reactions due to its steric hindrance.

1. Sodium methoxide
2. Sodium ethoxide
3. Potassium hydroxide
4. Potassium methoxide
5. Potassium tert-butoxide

Section: 6.18, 6.19

22. What is the major product of the following reaction?

1. I
2. II
3. III
4. IV

Section: 6.18, 6.19

23. What is the major product of the following reaction?

1. I
2. II
3. III
4. IV

Section: 6.18, 6.19

24. 
    What is the major product of the following reaction?

1. I
2. II
3. III
4. IV

Section: 6.18, 6.19

25. What is the major product of the following reaction?

1. I
2. II
3. III
4. IV

Section: 6.18, 6.19

26. What is the major product of the following reaction?

1. I
2. II
3. III
4. IV

Section: 6.18, 6.19

27. 
    What is the major product of the following reaction?

1. I
2. II