Chemistry, 10e (Brown)Chapter 25: The Chemistry of Life: Organic and Biological ChemistryMultiple-Choice and Bimodal

1) Hydrocarbons containing only single bonds between the carbon atoms are called __________. A) alkenes B) alkynes C) aromatics D) alkanes E) ketones Answer: D Diff: 1 Page Ref: Sec. 25.2

2) What general class of compounds is also known as olefins __________? A) alkenes B) alkynes C) aromatics D) alkanes E) ketones Answer: A Diff: 1 Page Ref: Sec. 25.2

3) The simplest alkyne is __________. A) ethylene B) ethane C) acetylene D) propyne E) benzene Answer: C Diff: 1 Page Ref: Sec. 25.2

4) The melting and boiling points of hydrocarbons are determined by __________. A) ion-dipole attraction B) dipole-dipole attraction C) London forces D) hydrogen bonding E) ionic bonding Answer: C Diff: 1 Page Ref: Sec. 25.2

5) Hydrocarbons containing carbon-carbon triple bonds are called __________. A) alkanes B) aromatic hydrocarbons C) alkynes D) alkenes E) olefins Answer: C Diff: 1 Page Ref: Sec. 25.2

6) Alkynes always contain a __________. A) C=C bond B) C≡C bond C) C–C bond D) C=H bond E) C≡H bond Answer: B Diff: 1 Page Ref: Sec. 25.2

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7) Alkenes always contain a __________. A) C=C bond B) C≡C bond C) C–C bond D) C=H bond E) C≡H bond Answer: A Diff: 1 Page Ref: Sec. 25.2

8) The molecular geometry of each carbon atom in an alkane is __________. A) octahedral B) square planar C) trigonal planar D) tetrahedral E) trigonal pyramidal Answer: D Diff: 1 Page Ref: Sec. 25.3

9) Hybridization of the carbon atom indicated by (*) in CH3–*CH2–CH3, *CH=CH2, and CH3–C≡CH is __________, __________, and __________, respectively. A) sp3, sp2, sp B) sp3, sp, sp2 C) sp, sp2, sp3 D) sp, sp3, sp2 E) sp2, sp3, sp Answer: A Diff: 2 Page Ref: Sec. 25.2

10) The minimum number of carbons necessary for a hydrocarbon to form a branched structure is __________. A) 4 B) 6 C) 3 D) 9 E) 12 Answer: A Diff: 1 Page Ref: Sec. 25.3

11) Cyclohexane has __________ fewer hydrogens than n-hexane. A) 0 B) 1 C) 2 D) 3 E) 4 Answer: C Diff: 1 Page Ref: Sec. 25.3 12) How many structural isomers of heptane exist __________? A) 2 B) 4 C) 6 D) 8 E) 10 Answer: D Diff: 2 Page Ref: Sec. 25.3 13) The general formula of an alkane is __________. A) C2nH2n+2

B) CnH2n

C) CnH2n+2

D) CnH2n-2

E) CnHn

Answer: C 2

Diff: 1 Page Ref: Sec. 25.3 14) Alkenes have the general formula __________. A) CnH2n

B) CnH2n-2 C) CnH2n+2

D) CnHn

E) C2nHn

Answer: A Diff: 1 Page Ref: Sec. 25.3

15) The compound below is an __________.

A) alkyne B) alkene C) alkane D) aromatic compound E) olefin Answer: A Diff: 1 Page Ref: Sec. 25.3

16) What is the name of the compound below __________?

A) 2,4-methylbutene B) 2,5-dimethylpentane C) 2,4-ethylbutene D) 2,4-dimethyl-1-pentene E) 2,4-dimethyl-4-pentene Answer: D Diff: 1 Page Ref: Sec. 25.3 17) Alkanes with __________ to __________ carbons are found in straight-run gasoline. A) 2, 3 B) 5, 12 C) 1, 5 D) 9, 15 E) 20, 60 Answer: B Diff: 1 Page Ref: Sec. 25.3

18) Gasoline and water do not mix because gasoline is __________. A) less dense than water B) less viscous than water C) nonpolar and water is polar D) volatile and water is not E) polar and water is nonpolar Answer: C

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Diff: 1 Page Ref: Sec. 25.3

19) Which substance would be the most soluble in gasoline __________? A) waterB) NaNO3

C) HClD) hexaneE) NaClAnswer: D Diff: 1 Page Ref: Sec. 25.3

22) The name of CH3–CH=C=CH-CH–CH=CH–CH3 is __________. A) 2, 3, 5 - octatriene B) 2, 5, 6 - octatriene C) 2, 3, 6 - octatriene D) 3, 5, 6 - octatriene E) 3, 4, 7 - octatriene Answer: C Diff: 1 Page Ref: Sec. 25.4 23) __________ could be the formula of an alkene. A) C3H8

B) C3H6

C) C6H6

D) C17H36 E) CH8

Answer: B Diff: 2 Page Ref: Sec. 25.4

24) In general, __________ are the most reactive hydrocarbons. A) alkenes B) alkynes C) alkanes D) cycloalkanes E) olefins Answer: B Diff: 1 Page Ref: Sec. 25.4

26) Aromatic hydrocarbons __________. A) readily undergo addition reactions like alkenes B) contain a series of π bonds on several consecutive carbon atoms C) undergo substitution reactions more easily than saturated hydrocarbons D) have sp2 hybridized carbon atoms E) are stabilized by resonance Answer: B Diff: 1 Page Ref: Sec. 25.5

27) How many hydroxyl groups are in a glycerol molecule __________? A) 0 B) 1 C) 2 D) 3 E) 4 Answer: D Diff: 1 Page Ref: Sec. 25.5

28) The general formula for an ether is __________. A) R–O–R' B) R–CO–R' C) R–CO–OH

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D) R–OHE) R–CO–H Answer: A Diff: 1 Page Ref: Sec. 25.5 30) The general formula of an aldehyde is __________. A) R–O–R' B) R–CO–R' C) R–CO–OH D) R–CHO E) R–CO–OR' Answer: D Diff: 1 Page Ref: Sec. 25.6

31) The general formula of a carboxylic acid is __________. A) R–O–R' B) R–CO–R' C) R–CO–OH D) R–H E) R–CO–OR' Answer: C Diff: 1 Page Ref: Sec. 25.6

32) Carboxylic acids can be formed by oxidation of __________. A) alkenes B) benzene C) ketones D) primary alcohols E) alkynes Answer: D Diff: 1 Page Ref: Sec. 25.6

33) The general formula of an ester is __________. A) R–O–R' B) R–CO–R' C) R–CO–OH D) R–OH E) R–CO–OR' Answer: E Diff: 1 Page Ref: Sec. 25.6

34) CH3CH2C(=O)NH2 is called a(n) __________. A) amine B) amide C) ketone D) aldehyde E) ester Answer: B Diff: 1 Page Ref: Sec. 25.6 35) The compound below is a(n) __________.

A) carboxylic acid B) ketone

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C) aldehyde D) ester E) amine Answer: D Diff: 1 Page Ref: Sec. 25.6

36) The hybridization of the central carbon atom in an aldehyde is __________. A) sp B) sp3

C) sp2

D) d2sp3

E) sp4

Answer: C Diff: 1 Page Ref: Sec. 25.6

37) Optically active molecules that are mirror images of each other are called __________. A) allotropes B) geometrical isomers C) enantiomers D) cofactors E) chiral compounds Answer: C Diff: 1 Page Ref: Sec. 25.7

40) Starch, glycogen, and cellulose are made of repeating units of __________. A) lactose B) glucose C) fructose D) sucrose E) amino acids Answer: B Diff: 1 Page Ref: Sec. 25.9

44) Which one of the following could be a cyclic alkane? A) C5H5

B) C3H6

C) C4H6

D) C2H6

E) C9H20

Answer: B Diff: 2 Page Ref: Sec. 25.3 46) How many isomers are possible for C4H10? A) 1 B) 2 C) 3 D) 4 E) 10 Answer: B Diff: 2 Page Ref: Sec. 25.3

47) How many isomers are possible for C5H12? A) 1 B) 2 C) 3 D) 4 E) 10 Answer: C Diff: 2 Page Ref: Sec. 25.3

50) What type of compound has been used to replace tetraethyl lead ((C2H5)4Pb) as an antiknock agent in gasoline?6

A) aromatic compounds B) olefins C) fluorochlorocarbons D) paraffins E) oxygenated hydrocarbons Answer: E Diff: 1 Page Ref: Sec. 25.3 51) How many structural isomers (include all types except optical) can be drawn for C5H10?A) 5 B) 6 C) 7 D) 11 E) 12 Answer: D Diff: 3 Page Ref: Sec. 25.4

57) Alcohols are hydrocarbon derivatives in which one or more hydrogens have been replaced by a hydroxyl functional group. __________ is the general formula of an alcohol. A) R–O–R B) R–CO–R C) R–CO–OH D) R–OH E) R–CO–H Answer: D Diff: 1 Page Ref: Sec. 25.5

58) Consider the following statements about alcohols:(i) Alcohols contain a polar O–H bond and hence mix well with polar solvents like water.(ii) Alcohols form hydrogen bonds with water.(iii) Alcohols have a higher boiling point compared to hydrocarbons with the same number of carbon atoms.(iv) For the most part, alcohols are toxic.

Which statement(s) is(are) true? A) none B) (i) and (ii) C) (iii) only D) (i), (ii), and (iv) E) all Answer: E Diff: 1 Page Ref: Sec. 25.5

59) Which one of the following is not an alcohol? A) acetone B) glycerol C) ethanol D) cholesterol E) ethylene glycol Answer: A Diff: 1 Page Ref: Sec. 25.5

60) Which one of the following compounds is an isomer of CH3CH2CH2CH2OH? A) CH3CH2CH2OH B)

C)

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D)

E) CH3OHAnswer: D Diff: 1 Page Ref: Sec. 25.5

61) What is the general formula for a ketone? A) R–O–R B) R–CO–R' C) R–CO–OH D) R–OH E) R–CHO Answer: B Diff: 1 Page Ref: Sec. 25.6

63) Of the compounds below, __________ is an isomer of

A)

B)

C)

D)

E)

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Answer: A Diff: 1 Page Ref: Sec. 25.6 64) Which structure below represents a ketone? A)

B)

C)

D)

E)

Answer: D Diff: 1 Page Ref: Sec. 25.6 65) Which structure below represents an aldehyde? A)

B)

C)

D)

E)

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Answer: C Diff: 1 Page Ref: Sec. 25.6 66) Which structure below represents an ether? A)

B)

C)

D)

E)

Answer: A Diff: 1 Page Ref: Sec. 25.6

67) Which of the following compounds does not contain a C=O bond? A) ketones B) aldehydes C) esters D) amides E) ethers Answer: E Diff: 1 Page Ref: Sec. 25.6 68) Which one of the following molecules is chiral? A)

B)

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C)

D)

E)

Answer: D Diff: 1 Page Ref: Sec. 25.7

69) How many chiral carbon atoms does the neopentane (2,2 - dimethylpropane) have? A) 0 B) 1 C) 2 D) 3 E) 4 Answer: A Diff: 1 Page Ref: Sec. 25.7

72) Sugars are examples of what type of molecule? A) proteins B) carbohydrates C) nucleic acids D) amino acids E) salts Answer: B Diff: 1 Page Ref: Sec. 25.10

Short Answer

5) Write the formula for 2-methyl-4-propylnonane. Answer:

Diff: 1 Page Ref: Sec. 25.3

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6) What is the correct name for the compound, CH3CH2CH=CHCH2CH=CHCH3? Answer: 2,5-octadiene Diff: 1 Page Ref: Sec. 25.4

7) What is the name of the compound below?

Answer: 4,6-dimethyl-1-heptyne Diff: 1 Page Ref: Sec. 25.4

14) What is the name of the compound CH3CH2CH(OH)CH2CH2CH3? Answer: 3-hexanol Diff: 1 Page Ref: Sec. 25.5

15) What functional group is characteristic of carboxylic acids? Answer: -COOH Diff: 1 Page Ref: Sec. 25.6

17) The primary ingredient in vinegar is __________ Answer: acetic acid Diff: 1 Page Ref: Sec 25.6

20) Mirror-image isomers of a substance are called __________. Answer: enantiomers Diff: 1 Page Ref: Sec. 25.7

Multiple ChoiceIdentify the choice that best completes the statement or answers the question.

____ 1. The correct IUPAC name of the compound is ____.

a. 3,4-dimethylpentane c. 2,3-dimethylpentaneb. 2,3-dimethylbutane d. 2,2,3-dimethylbutane

____ 2. Name the cycloalkane given below.

a. 1,2,4-trimethylcyclohexane c. 1,2,4-trimethylcyclopentaneb. 1,2,4-dimethylcyclopentane d. 1,3,5-trimethylcyclopentane

____ 3. The correct structural formula of 1,2-diethyl-2,3-dimethyl-6-propylcyclooctane is ____.

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a.

b.

c.

d.

____ 4. What is the nature of a covalent bond in alkanes?a. Ionic c. Nonpolar covalentb. Polar covalent d. Metallic

____ 5. The correct condensed structure of a compound having the IUPAC name 6-ethyl-6,7-dimethyl-2,4-dioctyne is ____.a.

b.

13

c.

d.

____ 6. Which is NOT an isomer of hexane?a. 2-methylpentane c. 2,3-dimethylbutaneb. 2,2-dimethylbutane d. 2-methyl-2-ethylbutane

____ 7. How are 3-methylheptane,3,3-dimethylhexane and 2-ethyl-4-methylpentane related to each other?a. They are geometric isomers. c. They are structural isomers.b. They are homologous. d. They are optical isomers.

____ 8. Which compound would show geometrical isomerism?a. 1-pentene c. 3-methylbutaneb. 3-methyl-1-butyne d. 2-pentene

____ 9. Which compound has an asymmetric carbon atom?a. 2,2-dimethylpentane c. 1-hexaneb. 2,3,4-trimethylhexane d. 2,2-dimethylpropane

____ 10. Which compound has a hydroxyl group?a. c.

b. d.

CompletionComplete each statement.

11. The structure of 3-ethyl-4-methylhexane is ____________________.

12. The IUPAC name of a compound represented by the line structure is ____________________.

13. The IUPAC name of is ____________________.

14. The IUPAC name of is ____________________.

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15. The molecular formula of octane is ____________________.

16. The correct structure of 4-methyl-2-pentanol is ____________________.

17. When small amounts of noxious material is added to ethanol, it becomes unfit for drinking and is known as ____________________.

Short Answer

18. Alkenes are hydrocarbons which are represented by the general formula . Write the molecular formula of an alkene that has four carbon atoms. Draw all the isomers possible by this formula and write the IUPAC name of all the isomers.

19. Draw the structures of 2,2,3-pentanetriamine and 1,3,5-cyclohexanetriol.

20. Name the type of reaction by which compounds can be converted into the products given below:a. 2-pentanol 2-pentanoneb. ethyl chloride ethene + hydrogen chloride

21. Use the structural formula to write the equation for the following reaction:1-pentanol 1-pentene + water

Problem

22. Write the IUPAC name of the following structure:

23. Draw the structure of 3,4,6-triethyl-5-methyloctane.

24. How many electrons are shared between the carbon atoms in ethene and ethyne? Draw their Lewis structures and calculate.

25. a. Find the molecular formula of alkenes having five and eight carbon atoms.b. Write the condensed structural formulas for these alkenes by putting a double bond between the first and

second carbon atom of the longest carbon atom chain.

26. A hydrocarbon has a formula . Identify the class of hydrocarbons to which it belongs. Also draw its condensed structural formula. If it is an alkene or an alkyne, use the double or triple bond at the first carbon of the longest chain.

27. Draw the structure of the compounds:a. 3,4-dimethyl-1-cyclobuteneb. 3-ethyl-2,4,6,8-tetramethyl-5-propyl-2,4,6-trinonene

28. Write the IUPAC name of the following compound:

29. Determine whether the given compound is a cis-or trans-isomer.

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F F

A A

30. Determine the IUPAC name of the following structure:

31. Write the IUPAC name of the following compounds:

a.

b.

32. Identify the functional group present in the compounds:

a. CH3-O-CH2CH3

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b.

33. Draw the structures of the following compounds and name the functional group of each.a. Methanamideb. Ethyl ethanoatec. Butanoic acidd. 3-hexanone

34. Name the functional group present in the following compound.

OH

35. Complete the IUPAC name of the following ester:

36. Complete the IUPAC name of the following aryl halide:

Br Cl

37. Write the IUPAC name of following compound:

Br

Essay

38. Alkane, alkene, and alkyne are various types of hydrocarbons.a Separate the alkanes, alkenes, and alkynes from the following list:

b Name the hydrocarbon that burns with oxygen and is used in welding.c Which hydrocarbon is used in the manufacture of plastic and artificial ripening of food?

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MULTIPLE CHOICE

1. ANS: CThe longest chain has five carbon atoms. The numbering of the chain is done such that all the alkyl groups get the lowest possible position number. The names selected for the alkyl groups and the parent chain are according to the IUPAC rules.

STA: 10d2. ANS: C

The compound is a cyclic hydrocarbon having a five-member carbon ring and a methyl group as a substituent at 1, 2, and 4 positions. The numbering of the cyclic ring is chosen such that the lowest possible numbers are given to the methyl groups.

STA: 10d3. ANS: D

The numbering of the carbon ring is chosen such that the lowest position numbers are given to the alkyl groups.4. ANS: C

The difference in the electronegativity of carbon and hydrogen is very small (0.35).5. ANS: B

The compound is an alkyne because there are two triple bonds between the carbon atoms in the chain. The longest chain has eight carbon atoms. The ethyl group is attached to carbon atom number 6 and the methyl groups are attached to carbon atom numbers 6 and 7.

6. ANS: DThe total number of carbon atoms in 2-methyl-2-ethylbutane is seven.

STA: 10d7. ANS: C

Structural isomers have the same molecular formula, but the atoms are bonded in a different order.

STA: 10d8. ANS: D

2-pentene has a double bond and the two groups attached to each of the double bonded carbon atom that are different.

9. ANS: B

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The carbon atom numbers 3 and 4 are asymmetric carbon atoms.10. ANS: A

Alcohols have a hydroxyl (OH) functional group.

STA: 10e

COMPLETION

11. ANS:

12. ANS: cyclopropane

STA: 10d13. ANS: 2-hexyne

STA: 10d14. ANS: 1-ethyl-2,3-dimethylbenzene

STA: 10d15. ANS:

STA: 10b

16. ANS:

STA: 10e17. ANS: denatured alcohol

SHORT ANSWER

18. ANS:The molecular formula of an alkene that has four carbon atoms is .

a.

1-butene

b.

trans-2-butene

19

c.

cis-2-butene

d.

2-methyl-1-propene19. ANS:

a. The structure of 2,2,3-pentanetriamine is .

b. The structure of 1,3,5-cyclohexanetriol is .

STA: 10e20. ANS:

a. Oxidationb. Elimination

21. ANS:

STA: 10e

PROBLEM

22. ANS:

5-ethyl-3,4,4-trimethyloctane

STA: 10d23. ANS:

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24. ANS:

a.

b.

In ethene, two electron pains are shared between the carbon atoms, and in ethyne, three electron pairs are shared between the carbon atoms.

STA: 10d25. ANS:

The general formula for alkenes is .a. and b. and

26. ANS:Alkyne

27. ANS:

a.

b.

28. ANS:5-ethyl-4-methylnonane

STA: 10d29. ANS:

Cis isomer30. ANS:

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1-ethyl-4-propyl-1-cyclohexene

STA: 10d31. ANS:

a. 1-bromo-2,4-dichloro-3-iodobenzeneb. 2,2,3-trifluro-3,4,4-triiodopentane

32. ANS:a. Etherb. Amine

STA: 10e33. ANS:

a. Amide

b. Ester

c. Carboxylic acid

d. Ketone

STA: 10e34. ANS:

Hydroxyl

STA: 10e35. ANS:

Propyl butanoate

STA: 10e36. ANS:

1-bromo-3-chloro-5-iodobenzene37. ANS:

2-bromobutane

ESSAY

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38. ANS:a The alkanes are , the alkenes are , and the alkynes are

.

b Ethyne is a hydrocarbon that burns with oxygen and is used in welding.

c Ethene is used in the manufacture of plastic and artificial ripening of food.

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