Chapter 23 1 Which of the following statements about carbon is false

General Chemistry: Atoms First, 2e (McMurry and Fay)

Chapter 23 Organic and Biological Chemistry

23.1 Multiple Choice Questions

1) Which of the following statements about carbon is false?

A) Carbon compounds have covalent bonds.

B) Carbon compounds can have multiple bonds.

C) Carbon is tetravalent.

D) Carbon uses sp2 hybrids to form tetrahedral structures.

2) The most important characteristic of carbon atoms for forming organic molecules is

A) ability to bond together to form long chains.

B) ability to form multiple covalent bonds.

C) use of hybrid orbitals.

D) all of the above are important

3) Another term for alkanes is

A) alkenes.

B) alkynes.

C) saturated hydrocarbons.

D) unsaturated hydrocarbons.

4) Compounds that have the same formula but different molecular structures are called

A) isoelectronic.

B) isomers.

C) isotones.

D) isotopes.

5) Which of the following statements about isomers is false?

A) All alkanes have branched chain isomers.

B) As the number of carbon atoms increase in a compound, so do the number of possible

isomers.

C) Isomers have different physical properties.

D) Isomers have the same formula but different molecular structures.

6) How many isomers are there for C5H12 ?

A) 3

B) 4

C) 5

D) 6

7) Which is the condensed structure of a straight-chain hydrocarbon?

A) I

B) II

C) III

D) IV

8) Which condensed structure below representing an alkane is not correct?

A) CH3CH2CH3

B)

C) CH3CH2CH2CH3

D)

9) Which of the following condensed structures represent the same molecule?

A) I and II

B) II and IV

C) III and IV

D) II and III

10) Which of the structures below are identical?

A) I and II

B) II and III

C) III and IV

D) I and IV

11) Some of the products from reaction of bromine and propane are shown below. (The

hydrogen atoms are not shown in the structures.) How many are identical structures?

A) 2

B) 3

C) 4

D) All are isomers of each other.

12) Which one of the structures below is different from the other three?

A) I

B) II

C) III

D) IV

13) Which of the following statements is false regarding functional groups?

A) The chemical properties of the functional group dictate the chemistry of the larger molecule.

B) Each functional group has a characteristic chemical behavior.

C) A functional group consists of an atom or a group of atoms that is part of a larger molecule.

D) A functional group consists of only carbon and hydrogen atoms.

14) Identify the functional group:

A) alcohol

B) amine

C) amide

D) ester

15) Identify the functional group:

A) aldehyde

B) ketone

C) ester

D) ether

16) Which functional group below represents a carboxylic acid?

A)

B)

C)

D)

17) Which functional group below represents a ketone?

A)

B)

C)

D)

18) Which functional group below represents an aldehyde?

A)

B)

C)

D)

19) The functional groups in the molecule below are

H2NCH2CO2H

A) alkane, amide, and carboxylic acid.

B) alkane, amine, and carboxylic acid.

C) alkane, amide, ketone, and alcohol.

D) alkane, amine, ketone, and alcohol.

20) Which one of the following compounds is an alcohol?

A) CH3OCH3

B) CH3COCH3

C) (CH3)2CHOH

D) CH3CO2H

21) The functional groups in the molecule below are

O O

HCCH2 COCH3

A) alkane, aldehyde, and ester.

B) alkane, aldehyde, ketone, and ether.

C) alkane, carboxylic acid, and ester.

D) alkane, ketone, and ester.

22) Which statement below is false concerning nomenclature rules for alkanes?

A) Carbon atoms are numbered starting with the atom farthest from the branching point.

B) Each branching group is assigned a number referring to its point of attachment in the parent

chain.

C) The name of the alkane is written as a single word.

D) The parent name is taken from the longest continuous chain of carbon atoms.

23) An alkyl group is named for the part of the alkane group that remains after a ________ is

removed.

A) C atom

B) CH3 group

C) CH2 group

D) H atom

24) If the point of attachment to an alkane is by the middle carbon in a propyl group, the group is

called

A) isopropyl.

B) n-propyl.

C) sec-propyl.

D) tert-propyl.

25) What is the name for the alkyl group:

A) isobutyl

B) tert-butyl

C) tributyl

D) trimethyl

26) What is the IUPAC name for the following compound?

A) heptane

B) 3, 3-dimethylpentane

C) 2, 2-dimethyl-2-ethylpropane

D) 2, 2-diethylpropane

27) What is the IUPAC name for the continuous carbon chain of C10H22?

A) decane

B) dipentane

C) tenalkane

D) tenane

28) What is the IUPAC name for the following compound:

A) 1, 3-dimethyl-1-ethylhexane

B) 4, 6-dimethyl-6-ethylhexane

C) 3, 5-dimethyloctane

D) sec-hexylbutane

29) Which of the following compounds is 5-ethyl-4-isopropyl-2-methylnonane?

A)

B)

C)

D)

30) Which name is not correct?

A) 1, 2-dichloropentane

B) 2, 3-dimethylbutane

C) 2-ethylbutane

D) 4-propylheptane

31) Which name is not correct?

A) 2, 2-dimethylbutane

B) 2, 3-dimethylpentane

C) 2, 3, 3-trimethylbutane

D) 2, 3, 3-trimethylpentane

32) The names of compounds with carbon-carbon double bonds contain the suffix

A) -ane.

B) -ene.

C) -yne.

D) -one.

33) Which class of hydrocarbons has the general formula CnH2n+2?

A) alkanes

B) alkenes

C) alkynes

D) cylcloalkanes

34) What class of hydrocarbons has the general formula CnH2n?

A) alkanes

B) alkenes and cycloalkanes

C) alkynes

D) aromatics

35) What is the hybridization of the carbon in (CH3)2C=CHC N indicated by the asterisk (*)?

A) sp

B) sp2

C) sp3

D) dsp3

36) Which compound is a saturated hydrocarbon?

A) benzene

B) cyclohexene

C) 2-methylpentane

D) propylene

37) What is the molecular geometry around the carbon in (CH3)2C=CHC N indicated by the

asterisk (*)?

A) linear

B) trigonal planar

C) trigonal pyramidal

D) tetrahedral

38) Which of the molecules shown below are unsaturated?

(1) CH3CH2CH2CH(CH3)2

(2) CH3CH=CHCH(CH3)2

(3) HC CCH2CH(CH3)2

A) All are unsaturated.

B) Only (2) and (3) are unsaturated.

C) Only (2) is unsaturated.

D) Only (3) is unsaturated.

39) Which of the following statements about cis–trans isomers is not correct?

A) Conversion between cis– and trans-isomers occurs easily by rotation around the double bond.

B) In the trans– isomer, the groups of interest are on opposite sides across the double bond.

C) In the cis– isomer, the groups of interest are on the same side of the double bond.

D) There are no cis-trans isomers in alkynes.

40) Which one of the following molecules can rotate freely around its carbon-carbon bond?

A) acetylene

B) cyclopropane

C) ethane

D) ethylene

41) How many geometrical and structural isomers are there of butene?

A) 3

B) 4

C) 5

D) 6

42) Which compound will have the largest dipole moment?

A) cis-1, 2-dichloroethylene

B) trans-1, 2-dichloroethylene

C) tetrabromoethylene

D) tetrachloroethylene

43) Which of the following is not a geometric (cis-trans) isomer?

A) 1, 1-dichloro-1-butene

B) 1, 2-dichloro-1-butene

C) 2-butene

D) 2-chloro-2-butene

44) Which of the following is trans-2-butene? (Only bonds are shown in the skeletal structures

below; the carbon and hydrogen atoms are deleted.)

A) structure a

B) structure b

C) structure c

D) none of these

45) What is the name of the following structure?

A) cis-1-ethyl-2-chloroethane

B) cis-1-chloro-1-butene

C) trans-1-chloro-1-butene

D) trans-1-chloro-2-ethylethane

46) What is the name of the following structure?

A) tert-butylethyne

B) 3, 3-dimethyl-1-pentyne

C) 3-ethyl-3-methyl-1-butyne

D) trans-ethylmethylbutyne

47) Which of the following is a correct name for an alkyne?

A) 3-methyl-2-pentyne

B) 5-methyl-3-pentyne

C) 2, 2-dimethyl-4-pentyne

D) 3, 3-dimethyl-1-pentyne

48) Which compound will exhibit cis-trans isomerism?

A) 1, 2-dichloroethane

B) 1, 2-dichloroethene

C) dichloroethyne

D) ethylene

49) The most important synthetic chemical reactions that alkenes and alkynes undergo are called

A) addition reactions.

B) combustion reactions.

C) photochemical halogenation reactions.

D) substitution reactions.

50) Name the product of hydrogenation of trans-2-pentene.

A) pentane

B) cis-2-pentene

C) trans-2-pentane

D) none of these

51) Hydrogenation of vegetable oils converts them into what type of molecule?

A) esters

B) ethers

C) polymers

D) saturated fats

52) Name the product obtained from the addition of bromine to 3-methyl-1-butene.

A) 1, 1-dibromobutane

B) 1, 2-dibromo-3-methylbutane

C) 1, 2-dibromopentane

D) trans-1, 2-dibromobutene

53) What is the product when pure water and ethene are mixed?

A) an alcohol

B) a carboxylic acid

C) an ether

D) no reaction occurs

54) In the addition reaction of water and propene in an acidic solution, the product is

A) an alcohol.

B) a carboxylic acid.

C) an ether.

D) a ketone.

17

55) The cycloalkane represented by a square is called ________ and has the molecular formula

________.

A) cyclopropane, C3H6

B) cyclopropane, C3H8

C) cyclobutane, C4H4

D) cyclobutane, C4H8

56) Which name is not correct?

A) 1, 1 dimethylcyclobutane

B) 1, 2-dimethylcyclobutane

C) 1, 3-dimethylcyclohexane

D) 1, 4-dimethylcyclopentane

57) A molecule that has the molecular formula is

A) 3-methlycyclopentene.

B) cyclohexane.

C) hexane.

D) 2-hexene.

58) What are the C–C–C bond angles in cyclopropane and cyclohexane?

A) 60° in both molecules

B) 60° in cyclopropane and 109.5° in cyclohexane

C) 60° in cyclopropane and 120° in cyclohexane

D) 109.5° in both molecules

59) Which compound is not an isomer of the other three?

A) cyclohexane

B) 1, 2-dimethylcyclobutane

C) 1, 2-dimethylcyclopropane

D) methylcyclopentane

60) Which of the following statements about cycloalkanes is true?

A) The bonds in cyclopropane and cyclobutane are weaker than other cycloalkanes.

B) Cycloalkanes are also called “acyclic” compounds.

C) Cyclopropane has 109° bond angles.

D) Most cycloalkanes are planar molecules.

61) Which of the following statements about benzene is true? Benzene

A) contains 3 long bonds and 3 short bonds.

B) is a puckered, six-membered ring.

C) is unusually stable because of delocalized pi electrons.

D) readily undergoes addition reactions.

62) What type of hybridization does a carbon atom have in a six-membered aromatic ring?

A) sp

B) sp2

C) sp3

D) sp3d

63) Which reaction is not characteristic of aromatic compounds?

A) addition

B) halogenation

C) nitration

D) sulfonation

64) Which structures represent the same dibromobenzene compound?

A) I and IV

B) II and III

C) I, II, and III

D) All structures are identical.

65) Which structure is meta-dibromobenzene?

A) structure I

B) structure II

C) structure III

D) structure IV

66) Which structure is para-dibromobenzene?

A) structure I

B) structure II

C) structure III

D) structure IV

67) Which of the following statements about amines is not correct? Amines are

A) bases (proton acceptors).

B) converted to ammonium salts by reaction with HCl.

C) organic derivatives of ammonia.

D) very water soluble.

68) The boiling point of 1-propanol should be ________ than the boiling point of methyl ethyl

ether.

A) higher than

B) lower than

C) the same as

D) cannot be determined

69) What is the proper name for (CH3)2CHCH(OH)CH3?

A) isopropanol

B) isopentanol

C) 2-methylpentanol

D) 3-methyl-2-butanol