practice problems series 1 ch1-ch6

Organic Chemistry

Carey/Giuliano

9th edition

Chapter 1

Copyright © 2014 The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

Question 1

What is the electronic configuration of carbon?

A) 1s2 2s2 2px2

B) 1s2 2s2 2px1 2py

12pz0

C) 1s2 2s2 2px12py

12pz1

D) 1s2 1px1 1py

12s2

Question 2

K+ is isoelectronic with what other element?

A) Ar

B) Ca

C) Na

D) Rb

Question 3

Select the correct Lewis structure for methyl

fluoride (CH3F).

A) B)

C) D)

Question 4

What is the correct Lewis structure of

formaldehyde (H2C=O)?

A) B)

C) D)

Question 5

In which of the compounds below is the d+ for

H the greatest?

A) CH4

B) NH3

C) SiH4

D) H2O

Question 6

Which of the following bonds have the greatest

dipole moment?

A) B)

C) D)

Question 7

Which of the following bonds have the greatest

dipole moment?

A) B)

C) D)

Question 8

How many constitutional isomers have the

formula C3H7Cl?

A) one

B) two

C) three

D) four

Question 9

The bond-line representation for

(CH3)2CHCH2CH2CHBrCH3 is

A) B)

C) D)

Question 10

How many constitutional alcohol isomers have

the molecular formula C4H10O?

A) two

B) three

C) four

D) five

Question 11

What is the formal charge of the sulfur atom in

the Lewis structure?

A) -1

B) 0

C) +1

D) +2

Question 12

What is the formal charge of the sulfur atom in

the Lewis structure given at the right?

A) -2

B) -1

C) +1

D) +2

Question 13

Which resonance structure contributes more to

the hybrid?

A) B)

Question 14

What is the molecular shape of the carbons of

acetylene (HCCH)?

A) tetrahedral

B) bent

C) trigonal planar

D) linear

Question 15

Select the chemical equation that depicts the

correct movement of electrons in the

reaction of ammonia with hydrogen chloride.

A) B)

C) D)

Question 16

Which of the following is most likely to have

ionic bonds?

A) HCl

B) Na2O

C) N2O

D) NCl3

Question 17

In which of the following is oxygen the positive

end of the bond dipole?

A) O-F

B) O-N

C) O-S

D) O-H

Question 18

The total number of unshared pairs of

electrons in the molecule is:

A) 0

B) 1

C) 2

D) 3

Question 19

Which of the following contains a triple bond?

A) SO2

B) HCN

C) C2H4

D) NH3

Answer Key – Chapter 1

1. B

2. A

3. C

4. C

5. D

6. D

7. A

8. B

9. A

10. C

11. C

12. D

13. B

14. D

15. C

16. B

17. A

18. D

19. B

Organic Chemistry

Carey/Giuliano

9th edition

Chapter 2

Copyright © 2014 The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

Question 1

In the most stable conformation of butane,

what is the dihedral angle between the

methyl groups?

A) 109.5°

B) 60°

C) 120°

D) 180°

Question 2

How many hydrogens are in a molecule of

isobutane?

A) 6

B) 8

C) 10

D) 12

Question 3

How many isomeric hexanes exist?

A) 2

B) 3

C) 5

D) 6

Question 4

What is the approximate C-C-C bond angle of

propane (CH3CH2CH3)?

A) 90°

B) 109.5°

C) 120°

D) 180°

Question 5

The correct IUPAC name for 2-ethylpentane is:

A) n-heptane

B) 2-methylpentane

C) 2-methylhexane

D) 3-methylhexane

Question 6

The correct structure of 3-ethyl-2-

methylpentane is:

A) B)

C) D)

Question 7

In 3-ethyl-2-methylpentane, carbon #3 (marked by a star) is classified as:

A) primary (1°)

B) secondary (2°)

C) tertiary (3°)

D) quaternary (4°)

Question 8

The second carbon of 2,2-dimethylbutane

(marked by a star) is classified as:

A) primary (1°)

B) secondary (2°)

C) tertiary (3°)

D) quaternary (4°)

Question 9

What is the correct IUPAC name for the

compound on the right?

A) 1-ethyl-2-methylcyclohexane

B) 2-ethyl-1-methylcyclohexane

C) 1-methyl-2-ethylcyclohexane

D) 2-methyl-1-ethylcyclohexane

Question 10

What is the correct IUPAC name for the

cycloalkane on the right?

A) undecane

B) cyclodecane

C) cycloundecane

D) cyclododecane

Question 11

Arrange octane, 2,2,3,3-tetramethylbutane and 2-methylheptane in order of increasing boiling point.

A) 2,2,3,3-tetramethylbutane < octane < 2- methylheptane

B) octane < 2-methylheptane < 2,2,3,3- tetramethylbutane

C) 2,2,3,3-tetramethylbutane < 2- methylheptane < octane

D) 2-methylheptane < 2,2,3,3- tetramethylbutane < octane

Question 12

To carry out the reaction shown below we need:

CH3OH H2C=O

A) an oxidizing agent

B) a reducing agent

Question 13

What is the hybridization of the starred carbon

in humulene (shown)?

A) sp

B) sp2

C) sp3

D) 1s2 2s2 2p2

Question 14

What is the hybridization of the starred carbon

of geraniol?

A) sp

B) sp2

C) sp3

D) 1s2 2s2 2p2

Question 15

The carbon skeleton shown at the bottom right accounts for 9 carbon atoms. How many

other isomers of C10H22 that have 7 carbons in their longest continuous chain can be generated by adding a single carbon to various positions on this skeleton? A) 2

B) 3

C) 4

D) 5

Question 16

How many primary carbons are in the molecule

shown at the bottom right?

A) 2

B) 3

C) 4

D) 5

Question 17

Which one contains the greatest number of

tertiary carbons?

A) 2,2-dimethylpropane

B) 3-ethylpentane

C) sec-butylcyclohexane

D) 2,2,5-trimethylhexane

Question 18

The systematic name for a sec-butyl group is:

A) 1-methylpropyl

B) 2-methylpropyl

C) 1,1-dimethylethyl

D) 1,2-dimethylethyl

Question 19

Which of the following is a 3-methylbutyl group?

A) CH3CH2CH2CH2CH2-

B) (CH3)2CHCH2CH2-

C) (CH3CH2)2CH-

D) (CH3)3CCH2-

Question 20

Which alkane has the highest boiling point?

A) hexane

B) 2,2-dimethylbutane

C) 2-methylpentane

D) 2,3-dimethylbutane

Answer Key – Chapter 2

1. D

2. C

3. C

4. B

5. D

6. B

7. C

8. D

9. A

10. C

11. C

12. A

13. C

14. B

15. B

16. C

17. C

18. A

19. B

20. A

Organic Chemistry

Carey/Giuliano 9th edition Chapter 3

Copyright © 2014 The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

Question 1 What is the relationship between the Newman

representations shown? A) identical B) constitutional isomers C) different conformations of the same compound D) stereoisomers

Question 2 What is the relationship between the Newman

representations shown? A) identical B) constitutional isomers C) different conformations of the same compound D) stereoisomers

Question 3

Select the least stable conformation of ethylene glycol.

A) B) C) D)

Question 4

Select the most stable conformation of butanoic acid.

A) B) C) D)

Question 5

Which compound has the greatest torsional strain in the planar conformation?

A) cyclopropane B) cyclobutane C) cyclopentane D) cyclohexane

Question 6

Rank the conformations of cyclohexane in order of decreasing stability.

A) chair > half-chair > twist-boat B) chair > twist-boat > half-chair C) twist-boat > half-chair > chair D) half-chair > twist-boat > chair

Question 7

The most stable conformation of cis-1-tert-butyl-4-methylcyclohexane has

A) both groups equatorial B) both groups axial C) the tert-butyl group axial and the methyl

equatorial D) the tert-butyl group equatorial and the

methyl axial

Question 8

The most stable conformation of trans-1-isopropyl-3-methylcyclohexane is:

A) B) C) D)

Question 9 What is the relationship between the two chair

conformations below? A) conformational isomers B) constitutional isomers C) different compounds D) stereoisomers

Question 10

What is the relationship between the two cyclohexane chairs below?

A) conformational isomers B) constitutional isomers C) stereoisomers D) different compounds

Question 11

Which of the following statements is not true concerning the chair-chair interconversion of

trans-1,2-diethylcyclohexane? A) An axial group will be changed into the

equatorial position. B) The energy of repulsions present in the

molecule will be changed. C) Formation of the cis substance will result. D) One chair conformation is more stable

than the other

Question 12

Which of the listed terms best describes the relationship between the methyl groups in the chair conformation of the substance shown?

A) eclipsed B) trans C) anti D) gauche

Question 13

Which of the following has an equatorial methyl group in its most stable conformation?

A) B) C) D)

Question 14

The structure shown is the carbon skeleton of adamantane, a hydrocarbon having a

structure that is a section of the diamond lattice. Adamantane is:

A) bicyclic B) tricyclic C) tetracyclic D) pentacyclic

Question 15

Which structure has the most strain? A) the eclipsed conformation of ethane B) the gauche conformation of butane C) the boat conformation of cyclohexane D) the skew boat conformation of

cyclohexane

Question 16 What is the IUPAC name for the compound

represented by the Newman projection? A) 1-tert-Butyl-1-isopropylethane B) 1-tert-Butyl-3-methylbutane C) 2-isopropyl-3,3-dimethylbutane D) 2,2,3,4-tetramethylpentane

Question 17 Which one of the following statements is true? A) Van der Waals strain in cis-1,2-

dimethylcyclopropane is the principal reason for its decreased stability relative to the trans

isomer. B) Cycloalkanes larger than cyclodecane rarely

occur naturally because they are too strained. C) One mole of cyclohexane gives off less heat

on being burned in air than one mole of any other cycloalkane.

D) The principal source of strain in the gauche conformation of butane is torsional strain.

Question 18

Which of the following statements best describes the most stable conformation of

trans-1,3-dimethylcyclohexane? A) Both methyl groups are axial. B) Both methyl groups are equatorial. C) One methyl groups is axial, the other

equatorial. D) The molecule is severely strained and

cannot exist.

Question 19 What is the relationship between the two

structures shown? A) Constitutional isomers B) Stereoisomers C) Different drawings of the same conformation of the same compound. D) Different conformations of the same

compound.

Question 20 The most stable conformation of the compound

to the right has A) an axial methyl group and an axial ethyl group. B) an axial methyl group and an equatorial ethyl group. C) an equatorial methyl group and an

equatorial ethyl group. D) an equatorial methyl group and an axial

ethyl group.

Answer Key – Chapter 3 1. C 2. B 3. C 4. B 5. D 6. B 7. D 8. B 9. A 10. C

11. C 12. D 13. D 14. B 15. C 16. D 17. A 18. C 19. A 20. D

Organic Chemistry

Carey/Giuliano 9th edition Chapter 4

Copyright © 2014 The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

Question 1 Name the compound on the right according to

the IUPAC system. A) 4-bromo-5-ethyl-2-methylheptane B) 4-bromo-3-ethyl-6-methylheptane C) 4-bromo-5-diethyl-2-methylpentane D) 4-bromo-3-ethyl-6-dimethylhexane

Question 2 Name the compound on the right according to

the IUPAC system. A) 3,4-dimethyl-2-hydroxypentane B) 2,3-dimethyl-4-pentanol C) 3,4-dimethyl-2-pentanol D) 2,3-dimethylpentyl-2-alcohol

Question 3 Name the compound on the right according to

the IUPAC system. A) trans-2-methylhydroxypentanol B) trans-2-methylcyclopentanol C) cis-2-methylhydroxypentanol D) cis-2-methylcyclopentanol

Question 4

What type of alcohol is 2-methyl-3-pentanol? A) primary (1°) B) secondary (2°) C) tertiary (3°) D) quaternary (4°)

Question 5

What is the product of the reaction of 2-methylcyclohexanol with HBr?

A) B) C) D)

Question 6

What product will be isolated from the reaction of 2-pentanol with HBr?

A) B) C) D)

Question 7

What is the rate-determining step in the reaction of cyclobutanol with HCl?

A) protonation of the OH group B) attack of the bromide on the carbocation C) simultaneous formation of the C-Br bond

and the breaking of the C-OH bond D) carbocation formation

Question 8

What are the best conditions to convert 1-pentanol into 1-chloropentane?

A) HCl, heat B) SOCl2, pyridine C) Cl2, CCl4 D) NaCl, H2O, heat

Question 9

Select the most stable carbocation. A) B) C) D)

Question 10

How many monochlorination products do you expect to obtain from the chlorination of

2-methylbutane? A) two B) three C) four D) five

Question 11

The step shown below is a _____________ step of the free-radical chlorination of

chloromethane. A) initiation B) propagation C) chain-terminating D) bond cleavage

Question 12

What is the major product of the radical bromination of 1-tert-butylcyclopentane?

A) B) C) D)

Question 13

Which one of the following reacts with HBr at the fastest rate?

A) B) C) D)

Question 14

Which of the following is the least able to serve as a nucleophile in a chemical reaction?

A) Br- B) OH- C) NH3 D) CH3

+

The species shown below represents _____ of the reaction between isopropyl alcohol and

hydrogen bromide. A) the alkyloxonium ion intermediate B) the transition step of the bimolecular

proton transfer C) the transition state of the attack of the

nucleophile on the carbocation D) the transition state of the unimolecular

dissociation

Question 15

Question 16 For the free-radical reaction below, light is

involved in which of the following reaction steps? A) Initiation only B) Propagation only C) Termination only D) Initiation and propagation

Question 17

How many monohalogenation products are possible? (Do not consider stereoisomers.)

A) 2 B) 3 C) 4 D) 5

Question 18

Which one of the following would not be a satisfactory method for the preparation of a

primary alkyl halide? A) Treatment of 1-hexanol with PBr3. B) Treatment of 4-methyl-1-pentanol with SOCl2. C) Treatment of 2-methylbutane with Br2 (light,

heat). D) Treatment of 1-decanol with NaBr and H2SO4

(heat).

Question 19 Which of the following best describes a mechanistic

feature of the free-radical bromination (Br2, light) of 2-methylpropane?

A) The initiation step involves cleavage of a C-H bond.

B) The free-radical (CH3)3C· is produced in one propagation step and reacts with Br2 in another.

C) The reaction is characterized by the homolytic cleavage of the C-Br bond.

D) The reaction is concerted; i.e., it occurs in a single step.

Question 20

An alkane with a molecular formula of C8H18 reacts with Cl2 in the presence of light and

heat to give a single monochloride C8H17Cl. What is the most reasonable structure for the starting alkane?

A) CH3CH2CH2CH2CH2CH2CH2CH3 B) (CH3CH2)2CHCH2CH2CH3 C) (CH3)2CHCH2CH2CH(CH3)2 D) (CH3)3CC(CH3)3

Answer Key – Chapter 4 1. A 2. C 3. B 4. B 5. D 6. B 7. D 8. B 9. C 10. C

11. B 12. D 13. C 14. D 15. D 16. A 17. C 18. C 19. B 20. D

Organic Chemistry

Carey/Giuliano

9th edition

Chapter 5

Copyright © 2014 The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

Question 1

Name the alkene below according to the

IUPAC system.

A) 2-bromo-5-heptane

B) 6-bromo-2-heptene

C) 2-bromo-5-heptene

D) 5-bromo-2-heptene

Question 2

How many alkenes will produce 3-ethylpentane

on catalytic hydrogenation?

A) 2

B) 3

C) 4

D) 5

Question 3

What is the major product of the dehydration of

2-methylcyclohexanol?

A) 1-methylcyclohexene

B) 2-methylcyclohexene

C) 3-methylcyclohexene

D) cyclohexene

Question 4

The major product of the dehydration of 1-

phenyl-2-propanol is

A) B)

C) D)

Question 5

Which alkene can have cis/trans stereoisomers?

A) B)

C) D)

Question 6

Of the compounds with the formula C3H5Cl,

which one has cis/trans isomers?

A) 1-chloropropene

B) 2-chloropropene

C) 3-chloropropene

D) all of them

Question 7

Assign the configuration of the alkenes below as Z or E, respectively.

A) E,E

B) E,Z

C) Z,Z

D) Z,E

Question 8

Rank the following alkenes in order of decreasing heat of combustion:

A) 3 > 1 > 2

B) 2 > 3 > 1

C) 1 > 2 > 3

D) 2 > 1 > 3

Question 9

The dehydration of 2-methyl-2-propanol cannot

be accomplished by using which of the

following reagents?

A) H2SO4

B) H3PO4

C) HCl

D) KHSO4

Question 10

What is the major product in the reaction of 2-

methyl-2-butanol with H2SO4 at 80°C?

A) B)

C) D)

Question 11

The reaction of 2-bromobutane with

KOCH2CH3 in ethanol produces trans-2-

butene. If the concentration of both

reactants is doubled, what would be the

effect on the rate of the reaction?

A) halve the rate

B) double the rate

C) quadruple the rate

D) no effect on the rate

Question 12

Which would react with KOCH2CH3 in ethanol

faster?

A) cis-2-tert-butylcyclohexyl bromide

B) trans-2-tert-butylcyclohexyl bromide

Question 13

Which would react with KOC(CH3)3/(CH3)3COH

faster?

A) cis-3-tert-butylcyclohexyl bromide

B) trans-3-tert-butylcyclohexyl bromide

Question 14

How many alkenes would you expect to be

formed from the E2 elimination of

3-bromo-2-methylpentane?

A) 2

B) 3

C) 4

D) 5

Question 15

Of the isomeric alcohols having the molecular

formula C5H12O, which one will undergo

acid-catalyzed dehydration most readily?

A) 2-pentanol

B) 2-methyl-1-butanol

C) 2-methyl-2-butanol

D) 3-methyl-2-butanol

Question 16

The heat of hydrogenation of cis-2-pentene is 117 kJ/mol. For which one of the following

alkenes is the heat of hydrogenation 126 kJ/mol?

A) 1-pentene

B) trans-2-pentene

C) 2-methyl-1-butene

D) 2,3-dimethyl-2-butene

Question 17

The molecular formula of b-Carotene is C40H56.

On catalytic hydrogenation, b-carotene is

converted to a saturated hydrocarbon of

molecular formula C40H78. How many rings

does b-carotene contain?

A) none

B) one

C) two

D) three

Question 18

Which one of the following best describes a mechanistic feature of the reaction of

3-bromopentane with sodium ethoxide?

A) The reaction occurs in a single step which is bimolecular.

B) The reaction occurs in two steps, both of which are unimolecular.

C) The rate-determining step involves the formation of the carbocation (CH3CH2)2CH+.

D) The carbon-halogen bond breaks in a rapid step that follows the rate-determining step.

Question 19

Which of the following statements is false?

A) tert-Butyl alcohol reacts with sodium faster than 1-butanol.

B) tert-Butyl alcohol reacts with hydrogen bromide faster than sec-butyl alcohol.

C) tert-Butyl alcohol undergoes acid-catalyzed dehydration faster than sec-butyl alcohol does.

D) tert-Butyl alcohol undergoes E2 elimination faster than tert-butyl fluoride does.

Question 20

The Zaitsev rule can be used to predict the major product of which one of the following

reactions?

A) 2-methylbutane + Cl2 (heat)

B) 2-methyl-2-butanol + Na

C) 2-methyl-2-butanol with HCl

D) 2-bromo-2-methylbutane + NaOCH2CH3 in ethanol (heat)

Question 21

Which reaction would be most likely to proceed

by an E1 mechanism?

A) 2-chloro-2-methylbutane + NaCH2CH3 in

ethanol (heat)

B) 1-bromo-2-methylbutane + KOC(CH3)3 in

DMSO

C) 2-bromo-2-methylbutane in ethanol

(heat)

D) 2-methyl-2-butanol + K

Question 22

Which one of the following groups has the highest rank when precedence is assigned

according to the Cahn-Ingold-Prelog system?

A) -CH2Cl

B) -CH=O

C) -C(CH3)3

D) CH2NH2

Question 23

How many alkenes, including stereoisomers,

contain a tert-butyl group and have the

molecular formula C7H14?

A) 3

B) 4

C) 5

D) 6

Answer Key – Chapter 5

1. B

2. A

3. A

4. C

5. D

6. A

7. A

8. D

9. D

10. B

11. C

12. A

13. B

14. B

15. C

16. A

17. C

18. A

19. A

20. D

21. C

22. A

23. B

Organic Chemistry

Carey/Giuliano

9th edition

Chapter 6

Copyright © 2014 The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

Question 1

Rank the following alkenes in order of

decreasing heat of hydrogenation.

A) 1 > 3 > 2

B) 3 > 2 > 1

C) 2 > 3 > 1

D) 1 > 2 > 3

Question 2

Which of the alkenes below will produce 2-

methylbutane on catalytic hydrogenation?

A) 1 and 3

B) 1, 2 and 3

C) 2 and 4

D) 2, 3 and 4

Question 3

Which carbocation forms when 3-methyl-2-

pentene is protonated?

A) B)

Question 4

Which alkene has the lowest heat of

hydrogenation?

A) B)

C) D)

Question 5

The reaction of 3-methyl-1-butene with HBr

produces 2-bromo-3-methylbutane and

which other alkyl halide?

A) B)

C) D)

Question 6

What is the product of the reaction of 1-

methylcyclohexene with HCl?

A) B)

C) D)

Question 7

What is the correct IUPAC name of the

compound isolated from the reaction of

2-methyl-2-pentene with HBr in the

presence of peroxides?

A) 3-bromo-4-methylpentane

B) 3-bromo-2-methylpentane

C) 2-bromo-2-methylpentane

D) 2,3-dibromo-2-methylpentane

Question 8

The product isolated from the acid-catalyzed

hydration of cis-3-methyl-2-pentene is:

A) 2-ethyl-2-butanol

B) 2-ethyl-1-butanol

C) 3-methyl-2-pentanol

D) 3-methyl-3-pentanol

Question 9

Which alkene will undergo acid-catalyzed

hydrolysis at the fastest rate?

A) B)

C) D)

Question 10

What is the product of the addition of Br2 to

cyclopentene?

A) B)

C) D)

Question 11

Arrange the alkenes in order of decreasing rate of reaction toward bromine addition:

2-methyl-1-butene, 2-methyl-2-butene, and 3-methyl-1-butene

A) 2-methyl-1-butene > 3-methyl-1-butene > 2-methyl-2-butene

B) 3-methyl-1-butene > 2-methyl-1-butene > 2-methyl-2-butene

C) 2-methyl-2-butene > 2-methyl-1-butene > 3-methyl-1-butene

D) 2-methyl-2-butene > 3-methyl-1-butene > 2-methyl-1-butene

Question 12

The ozonolysis of 2,4-dimethyl-2-pentene will

produce:

A) B)

C) D)

Question 13

Which combination of reagents is the best choice for carrying

out the conversion shown?

A) 50% water - 50% sulfuric acid

B) 1. H2SO4

2. H2O, heat

C) 1. O3

2. H2O, Zn

D) 1. BH3-THF

2. H2O2, NaOH

Question 14

Which one of the following terms best applies

to the hydrogenation of an alkene in the

presence of finely divided platinum? (in

ethanol as solvent)

A) anti addition

B) Concerted reaction

C) heterogeneous catalysis

D) endothermic reaction

Question 15

Which reagent reacts with an alkene to

produce an epoxide?

A) B)

C) D)

Question 16

Hydroboration-oxidation of which one of the

following yields a primary alcohol as the

major product?

A) B)

C) D)

Question 17

Which one of the following is not stereospecific?

A) reaction of cis-2-butene with peroxyacetic acid

B) hydroboration-oxidation of 1- methylcyclopentene

C) addition of Br2 to trans-2-pentene

D) addition of HBr to cis-2-butene in the presence of peroxides

Question 18

Which alkene reacts with HCl (electrophilic

addition) at the fastest rate?

A) B)

C) D)

Question 19

Which one of the following outlines the best synthesis of trans-2-chlorocyclohexanol?

A) Heat a mixture of cyclohexanol and Cl2 to 400oC.

B) 1. Treat cyclohexene with HCl;

2. Treat product of reaction 1 with peroxyacetic acid.

C) 1. Hydrogenation of cyclohexene in the presence of Pt;

2. Treat product of reaction 1 with Cl2 in H2O.

D) 1. Treat bromocyclohexane with KOC(CH3)3 in DMSO;

2. Treat product of reaction 1 with Cl2 in water.

Answer Key – Chapter 6

1. A

2. A

3. B

4. C

5. B

6. A

7. B

8. D

9. D

10. A

11. C

12. B

13. D

14. C

15. C

16. A

17. D

18. C

19. D