25) None of the listed compounds contains a ring. Which could have one carbon-carbon triple bond?
A) C3H8
B) C2H2
C) C10H20
D) All of these
26) None of the listed compounds contains a ring. Which has at least one singly-bonded carbon atom?
A) C5H12
B) C4H6
C) C6H12
D) All of these
27) Which one of the following molecules can rotate freely around its carbon-carbon bond?
A) benzene
B) cyclopropane
C) pentane
D) ethene
28) Which of the following is a correct name for an alkyne?
A) 3-methyl-2-octyne
B) 8-methyl-3-octyne
C) 2, 2-dimethyl-4-pentyne
D) 3, 3-dimethyl-1-heptyne
29) Name the product obtained from the addition of chlorine to 3-methyl-1-octene.
A) 1, 1-dichlorooctane
B) 1, 2-dichloro-3-methylbutane
C) 1, 2-dichlorononane
D) trans-1, 2-dichlorooctene
30) The smallest alkyne is called
A) ethene.
B) propene.
C) 1-butyne.
D) acetylene.
31) Identify the saturated compound, assuming none of the structures are rings.
A) C3H6
B) C3H8
C) alkyne
D) C7H12
32) Which name is not correct?
A) 1, 1-dimethylcyclopentane
B) 1, 2-dimethylcyclopentane
C) 1, 3-dimethylcyclooctane
D) 1, 4-dimethylcyclopentane
33) Which of the following does not contain a carbonyl group, C=O?
A) an alkene
B) a ketone
C) an amide
D) an ester
34) Which ending on a ketone or aldehyde indicates a sugar?
A) -ene
B) –one
C) ether
D) -ose
35) Which of the following is not a geometric (cis-trans) isomer?
A) 1, 1-dichloro-1-pentene
B) 1, 2-dichloro-1-hexene
C) 2-hexene
D) 2-chloro-2-heptene
36) Identify the alkene that cannot be drawn cis and trans.
A) 2-pentene
B) 3-hexene
C) 4-octene
D) 1-hexene
37) Identify the compounds that have at least one sp2 hybridized carbon.
A) 1-pentyne
B) propane
C) 2-butene
D) 3-chloropentane
38) Which of the following atoms is expected to be sp2 hybridized?
A) C in C2H6
B) C-H in C3H4
C) O in CH3CH2OH
D) O in CHO
39) Which one of the following amino acids does not contain a basic side chain?
A) arginine
B) histidine
C) lysine
D) glutamine
40) Which one of the following amino acids contains a polar side chain?
A) valine
B) glycine
C) cysteine
D) alanine
41) Which one of the following amino acids contains a hydrophobic side chain?
A) alanine
B) asparagine
C) cysteine
D) glutamine
42) In the protein, Val-Tyr-His-Pro, which amino acid contains the N-terminal group?
A) histidine
B) proline
C) tyrosine
D) valine
43) In the protein, Asn-Phe-Cys-Lys, which amino acid contains the C-terminal group?
A) aspargine
B) cysteine
C) lysine
D) phenylalanine
44) All reactions in the human body are catalyzed by
A) carboxylic acids.
B) alcohols.
C) proteins.
D) alkanes.
45) Keratin is found in
A) cells.
B) bird feathers.
C) muscles.
D) DNA.
46) The human body can synthesize ________ amino acids.
A) 3
B) 11
C) 8
D) 15
47) The human body is thought to contain ________ different kinds of proteins.
A) 90,000
B) 150,000
C) 200,000
D) 110,000
48) Approximately what mass percent of a body’s dry weight consists of proteins?
A) 5%
B) 40%
C) 50%
D) 70%
49) A peptide bond links
A) an alcohol and a ketone.
B) an amine and an aldehyde.
C) an amine and a carboxylic acid.
D) an ester and a carboxylic acid.
50) How many alpha amino acids commonly make up the different proteins found in humans?
A) 6
B) 20
C) 22
D) 12
51) Which one of the following amino acids contains a basic side chain?
A) proline
B) cytosine
C) glutamic acid
D) arginine
52) Which of the following amino acids is acidic?
A) alanine
B) aspartic acid
C) glutamine
D) histidine
53) Which one of the following amino acids contains a polar side chain?
A) alanine
B) glycine
C) serine
D) histidine
54) Which of the following amino acids contains a benzyl group?
A) isoleucine
B) proline
C) asparagine
D) tryrosine
55) Which one of the amino acids contains a double ring structure?
A) alanine
B) serine
C) tryptophan
D) histidine
56) Which amino acid has the simplest structure?
A) valine
B) glycine
C) asparagine
D) arginine
57) Which of the following amino acids contains a sulfur in its side chain?
A) aspartic acid
B) glycine
C) cysteine
D) arginine
58) Which one of the following amino acids contains a hydrophobic side chain?
A) leucine
B) cysteine
C) glutamine
D) lysine
59) All but one of the common amino acids contain a –NH2 amino group. Which one contains an –NH–
amino group as part of a ring structure?
A) phenylalanine
B) proline
C) tyrosine
D) arginine
60) In leu-ala-arg-val-tyr-his-pro-gln, the amino acid with the N-terminal is
A) gln.
B) val.
C) leu.
D) tyr.
105
61) The structure of DNA was proposed by
A) Einstein.
B) Curie.
C) Watson and Crick.
D) Copernicus.
23.3 Short Answer Questions
1) In organic molecules the molecular geometry exhibited by carbon is ________ when carbon is bonded
to four atoms by four single bonds, ________ when carbon is bonded to three atoms by one double bond
and two single bonds, and ________ when carbon is bonded to two atoms by one triple bond and one
single bond.
2) The H-C-H bond angles in C2H6, C2H4, and C2H2 are ________, ________, and ________, respectively.
3) Orbitals used by carbon for bonding in C2H6, C2H4, and C2H2 are ________, ________, and ________,
respectively.
4) The C-Br bond in CH3Br is a ________ (nonpolar, polar) covalent bond with a ________ (δ+, δ-) charge
on the carbon atom and a ________ (δ+, δ-) charge on the bromine atom.
5) The C-Br bond in CH3CH2Li is a ________ (nonpolar, polar) covalent bond with a ________ (δ+, δ–)
charge on the carbon atom and a ________ (δ+, δ-) charge on the lithium atom.
6) Organic molecules containing only carbon and hydrogen and having only single bonds are called
________ hydrocarbons, or ________.
7) How many isomers exist for C5H12? Of these isomers, how many are straight-chain isomers and how
many are branched isomers?
8) Do the condensed structures shown below represent the same or different molecules?
(1) CH3CH2CH2CH2CH(CH3)2
(2) CH3
|
CH3CHCH2CH2CH2CH3
9) Do the two condensed structures (1) and (2) below represent the same or different molecules?
CH3 CH3 CH3
| | |
CH3CHCH2CHCH3 CH3CHCH2CHCH3
|
CH3
(1) (2)
10) The number of different monochloro substitution products (C5H11Cl) that can form from the reaction
of 2-methylbutane with Cl2 is ________.
11) The number of different monochloro substitution products (C5H11Cl) that can form from the reaction
of 2,2-dimethylpropane with Cl2 is ________.
12) The combustion of methane has a standard enthalpy of combustion H° = -802 kJ per mole of methane
burned. How many kilojoules of heat are released if 1.28 grams of oxygen are consumed in the reaction?
13) The condensed formula of the smallest molecule that contains the ether functional group is ________.
14) In the dark the reaction of 2-pentene with bromine will form how many different products?
15) C2H6O is the empirical formula for both ethyl alcohol, CH3CH2OH and dimethyl ether, CH3OCH3.
In order to boil CH3CH2OH the strongest intermolecular forces that must be overcome are (London
dispersion, dipole-dipole, hydrogen bonding) forces. In order to boil CH3OCH3 the strongest
intermolecular forces that must be overcome are (London dispersion, dipole-dipole, hydrogen bonding)
forces. Which compound is expected to have the higher boiling point?
16) The molecule H2NCH2CH2CH2OH contains an ________ functional group and an ________
functional group.
17) The molecule CH3CH2CO2CH2CO2H contains an ________ functional group and a ________
functional group.
18) The condensed structures for the two isomers of C4H10 are (1) ________ and (2) ________.
19) The IUPAC name for the alkane shown below is ________.
CH3
|
CH3CHCH2CH2CH2CH3
20) The alkane, 3-ethyl-3-methylhexane contains ________ carbon atoms and ________ hydrogen atoms.
21) (CH3)3C— represents a ________ (normal, secondary, tertiary) butyl group.
22) What is the empirical and molecular formulas of 1–tert-butyl-2-methylcyclodecane?
23) The molecules CH3CH2CH2CH2CCH and CH3CH2CH2CH2CH=CH2, respectively, belong to the
________ family and the ________ family of organic molecules.
24) The cycloalkane represented by a heptagon is named ________ and has the molecular formula
________.
25) Monosaccharides are classified as either ________ or ________.
26) Linoleic acid, a fatty acid, contains ________ carbons and ________ double bonds.
27) Naturally occurring organic molecules that dissolve in nonpolar solvents are called ________ of which
the most plentiful in nature are ________ and ________.
28) The amide bonds that form when two or more amino acids link together are called ________ bonds.
29) Does tyrosine contain an aromatic ring?
30) Cytosine is a base that occurs in ________ (DNA, RNA, DNA and RNA).
31) The four cyclic amine bases that occur in DNA are ________, ________, ________, and ________.
32) The sugar in RNA is ________.