CH20 p.738-740
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20
12:44 PM
Page 738
OXIDATION—REDUCTION REACTIONS
Reviewing Content
27. The oxidizing agent is reduced.
37. a.
b.
c.
d.
28. a. Ba(s) + O2(g) ! 2BaO(s); barium is
oxidized
b. CuO(s) + H2(g) ! Cu(s) + H2O(l);
copper is reduced
c. C2H4(g) + 3O2(g) ! 2CO2(g) + 2H2O(l);
carbon is oxidized
d. 3CaO(s) + 2Al(s) ! Al2O3(s) + 3Ca(s);
calcium is reduced
38. a. 2Al(s) + 3Cl2(g) ! 2AlCl3(s)
b. 2Al(s) + Fe2O3(s) ! Al2O3(s) + Fe(s)
c. 3Cl2(g) + 6KOH (aq) ! KClO3(aq) +
5KCl(aq) + 3H2O(l)
d. 2HNO3(aq) + 3H2S(aq) ! 3S(s) +
2NO(g) + 4H2O(l)
e. KIO4(aq) + 7KI(aq) + 8HCl(aq) !
8KCl(aq) + 4I2(s) + 4H2O(l)
29. a.
b.
c.
d.
oxidation
oxidation
oxidation
oxidation
39. redox: a, b, c, d, e
30. a.
b.
c.
d.
oxidizing agent
reducing agent
oxidizing agent
oxidizing agent
31. a.
b.
c.
d.
H2 is oxidized; S is reduced.
N2 is reduced; H2 is oxidized.
S is oxidized; O2 is reduced.
H2 is oxidized; O2 is reduced.
26. oxidation
33. An oxidation number is the charge an
atom would have if the electrons in each
bond were assigned to the atoms of the
more electronegative element.
34. c is false.
35. a.
b.
c.
d.
e.
+2
+3
Na, +1; Cr, +6
+5
+7
36. a.
b.
c.
d.
e.
O, –2; H, +1
P, +5; O, –2
I, +5; O, –2
H, +1; P, +5; O, –2
H, +1; S, +6; O, –2
738
Core Teaching Resources
40. a. 4MnO4–(aq) + 3ClO2 –(aq) + 2H2O(l) !
4MnO2(s) + 3ClO4– –(aq) + 4OH–(aq)
b. 2Cr3+–(aq) + 3ClO– –(aq) + 10OH– –(aq)
! 2CrO42– –(aq) + 3Cl– –(aq) + 5H2O(l)
c. 6Mn3+–(aq) + I– –(aq) + 6OH–(aq) !
6Mn2+–(aq) + IO3– –(aq) + 3H2O(l)
Understanding Concepts
41. a.
b.
c.
d.
4Al(s) + 3MnO2(s) ! 2Al2O3(s) + 3Mn(s)
2K(s) + 2H2O(l) ! 2KOH(aq) + H2(g)
2HgO(s) ! 2Hg(l) + O2(g)
P4(s) + 5O2(g) ! P4O10(s)
42. a. 2Li(s) + 2H2O(l) ! 2LiOH(aq) + H2(g)
b. K2Cr2O7(aq) + 14HCl(aq) ! 2KCl(aq) +
2CrCl3(aq) + 7H2O(l) + 3Cl2(g)
c. 2Al(s) + 6HCl(aq) ! 2AlCl3(aq) + 3H2(g)
d. Cl2(g) + H2O(l) ! HCl(aq) + HClO(aq)
e. I2O5(s) + 5CO(g) ! I2(s) + 5CO2(g)
f. H2O(l) + SO3(g) ! H2SO4(aq)
43. a.
b.
c.
d.
e.
f.
+4
+5
+5
+3
+5
+3
44. K2CrO4, Cr +6; K2Cr2O7, Cr +6
45. a. Cl oxidized, Mn reduced, Mn oxidizing
agent, reducing agent
b. Cu oxidized, N reduced, N oxidizing
agent, Cu reducing agent
c. P oxidized, N reduced, N oxidizing
agent, P reducing agent
d. Sn oxidized, Bi reduced, Bi oxidizing
agent, Sn reducing agent
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32. a. H2 is the reducing agent; S is the
oxidizing agent.
b. N2 is the oxidizing agent; H2 is the
reducing agent.
c. S is the reducing agent; O2 is the
oxidizing agent.
d. H2 is the reducing agent; O2 is the
oxidizing agent.
Al is oxidized; Mn is reduced.
K is oxidized; H is reduced.
Hg is reduced; O is oxidized.
P is oxidized; O is reduced.
CH20 p.738-740
7/9/04
12:44 PM
Page 739
46. a. MnO2(s) + 4HCl(aq) ! MnCl2(aq) +
Cl2(g) + 2H2O(l)
b. Cu(s) + 4HNO3(aq) ! Cu(NO3)2(aq) +
2NO2(g) + 2H2O(l)
c. 3P(s) + 5HNO3(aq) + 2H2O(l) ! 5NO(g)
+ 3H3PO4(aq)
d. 2Bi(OH)3(s) + 3Na2SnO2(aq) ! 2Bi(s) +
3Na2SnO3(aq) + 3H2O(l)
47. a. 16H+(aq) + 2Cr2O72–(aq) + C2H5OH(aq) !
4Cr3+(aq) + 2CO2(g) + 11H2O(l)
b. oxidizing agent
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48. a. WO3(s) + 3H2(g) ! W(s) + 3H2O(g)
b. H2
c. H
56. A sodium atom achieves a stable electron
configuration by losing its one valence
electron making it a reducing agent. A
sodium ion has a stable electron
configuration.
57. Double-replacement reactions never
involve the transfer of electrons; instead
they involve the transfer of positive ions in
aqueous solution.
58. In every redox reaction one species loses
one or more electrons and is a reducing
agent. Another substance gains one or
more electrons and is an oxidizing agent.
SO42–
H2O2
NO3–
Cr2O72–
H2O
49. a. oxidized
b. H is the oxidizing agent; Ag is the
reducing agent.
c. 2Ag(s) + H2S(s) ! Ag2S(s) + H2(g)
59. a.
b.
c.
d.
e.
50. Lead atoms are oxidized by losing 2
electrons to form Pb2+ ions. Oxygen atoms
are reduced by gaining 2 electrons to form
O2– ions.
60. Group 1A metals; a reducing agent must
give up electrons. Group 1A metals achieve
stability by giving up electrons and forming
positively charged ions.
51. a. Yes, the oxidation number of bismuth
changes from +3 to zero; the oxidation
number of carbon changes from zero to
+2.
b. No, there is no change in oxidation
number of any of the atoms in this
reaction.
c. No, there is no change in oxidation
number of any of the atoms in this
reaction.
61. a. Rb(s) + I2(s) ! RbI2(s); oxidizing agent is I
b. Ba(s) + 2H2O(l) ! Ba(OH)2(aq) + H2(g);
oxidizing agent is H
c. 2Al(s) +3FeSO4(aq) ! Al2(SO4)3(aq) +
3Fe(s); oxidizing agent is Fe
d. C4H8(g) + 6O2(g) ! 4CO2(g) + 4H2O(l);
oxidizing agent is O
e. Zn(s) + 2HBr(aq) ! ZnBr2(aq) + H2(g);
oxidizing agent is H
f. Mg(s) + Br2(l) ! MgBr2(s), oxidizing
agent is Br
52. N2O4(l) + 2N2H4(l) ! 3N2(g) + 4H2O(g)
Based on oxidation number changes,
nitrogen atoms from N2O4 gain electrons in
forming N2 and nitrogen atoms from H2H4
lose electrons in forming N2.
53. a.
b.
c.
d.
reactant, 0; product, +3
reactant, –2; product, –2
X
H
Critical Thinking
54. When one reactant loses electrons another
reactant must gain them.
55. 1s2 2s2 2p6 3s2 3p5
A chlorine atom can “lose” its seven valence
electrons or it can gain one electron to
complete the third energy level.
62. Rhenium is oxidized and selenium is
reduced, because the bonded electrons
would shift toward the more
electronegative element, selenium.
63. MnO4–, because the manganese is at its
highest oxidation state.
Concept Challenge
64. 0.406 g Cu
65. 104 mL K2Cr2O7
66. a. 5CO + I2O5 ! I2 + 5CO2
b. C is oxidized. I is reduced.
c. 0.22 g CO
67. a. +5
b. –3
c. +3
Solutions Manual
739
CH20 p.738-740
7/9/04
d.
e.
f.
g.
h.
12:44 PM
Page 740
74. suspension; particles settle out of a
suspension; not a solution
+3
+1
–3
+2
+4
75. a, c, and d
68. 2F2 + O2 ! 2F2O; fluorine is oxidized;
oxygen is reduced
69. Nitride ion has the minimum oxidation
number of -3, therefore it cannot gain
additional electrons and be an oxidizing
agent. It can lose electrons however and be
a reducing agent. Nitrate ion has the
maximum oxidation number of +5,
therefore it cannot lose additional electrons
and be a reducing agent. It can gain
electrons however and be an oxidizing
agent.
70. a. 3Hg2+ + 2Al ! 3 Hg + 2Al3+
b. MnO2 + 4H+ + Fe ! Mn2+ + 2H2O + Fe2+
c. 2Fe3+ + Cd ! 2Fe2+ + Cd2+
71. a.
CO2
produced
(mol)
H2O
produced
(mol)
CH4
2
1
2
C2H6
3.5
2
3
C3H8
5
3
4
C4H10
6.5
4
5
C5H12
8
5
6
C6H14
9.5
6
7
b. CxHv + [x + (y/4)]O2 ! xCO2 + (y/2)H2O
740
Core Teaching Resources
78. 0.379 M H3PO4
79. Solubility PbBr2 = 8.1 " 10–3M
80. Test tube B has the NaCl added to it. Due to
the common ion effect, the addition of
either sulfate ion or barium ion to a
saturated solution of BaSO4 will cause the
solubility product of BaSO4 to be exceeded
and barium sulfate will precipitate as
shown in test tubes A and C.
82. 56.3 mL KOH
83. a. NH4+ and NH3; H2O and H3O+
b. H2SO3 and HSO3–; NH2– and NH3
c. HNO3 and NO3–; I– and HI
84. a.
b.
c.
d.
acidic
basic
basic
acidic
85. a.
b.
c.
d.
5.00
10.00
13.00
6.52
86. large
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Alkane
burned
O2
used
(mol)
73. 1.8 " 102 kPa
77. Ca(NO3)2; boiling point elevation is a
colligative property that depends on the
number of particles in solution. Ca(NO3)2
gives three particles per formula unit; LiF
gives two particles per formula unit.
81. a. 1.0 " 10–2M
b. 1.0 " 10–11M
c. 1.6 " 10–9M
Cumulative Review
72. sublimation
76. Dilute 110 mL of 6.0M HCl to 440 mL total
volume.
CH21 p.741-743
7/9/04
12:44 PM
21
Page 741
ELECTROCHEMISTRY
Reviewing Content
26. An equation that represents the oxidation
or the reduction in a redox reaction.
27. Oxidation: Al(s) ! Al3+(aq) + 3e–
Reduction: Cu2+(aq) + 2e– ! Cu(s)
28. Nothing
29. a.
b.
c.
d.
e.
f.
Cu
Ca
Mg
Sn
Zn
Al
30. cathode
31. The salt bridge allows ions to pass from
one half-cell to the other but prevents the
solutions from mixing.
32. anode: zinc, cathode: carbon (graphite)
33. Water is produced by the redox reaction
and sulfuric acid is used up; water has a
lower density than sulfuric acid.
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34. Pb(s)|PbSO4(aq)||PbO2(s)|PbSO4(s)
43. A direct current flows in one direction
only.
44. The teaspoon is the cathode in an
electrolytic cell with silver cyanide as the
electrolyte. When the DC current flows,
the silver ions deposit as silver on the
teaspoon.
45. 2H2O(l) ! O2(g) + 2H2(g)
46. electrode A
47. The small spheres representing molecules
of H2 and Cl2 would be in 1:1 ratio.
48. Voltaic cells convert chemical energy into
electrical energy. Electrolytic cells use
electrical energy to cause a chemical
reaction.
49. Two half-cells are needed because
oxidation or reduction cannot occur in
isolation. One half-cell gains electrons
and one loses them, producing an electric
current.
Understanding Concepts
35. Fuel cells cannot generate electricity as
economically as more conventional forms
of electrical generation.
50. The anode and cathode grids are both
packed with PbSO4. The electrolyte is very
dilute sulfuric acid.
36. A fuel cell needs no recharging; it does not
produce toxic wastes; and if the fuel is
hydrogen gas, it is lighter.
51. Some of the iron dissolves and the nail
becomes coated with copper.
Oxidation: Fe ! Fe2+ + 2e–
37. It was arbitrarily set at zero.
Reduction: Cu2+ + 2e– ! Cu
38. the ability of a voltaic cell to produce a
current
Fe(s) + CuSO4(aq) ! FeSO4(aq) + Cu(s)
39. The relative order is the same because
both tables rank the elements according
to their tendency to undergo
oxidation/reduction.
40. Connect the aluminum half-cell to a
standard hydrogen half-cell and use a
voltmeter. The indicated voltage is the
standard reduction potential for the
aluminum half-cell.
41. a. nonspontaneous, –0.34 V
b. nonspontaneous, –1.24 V
52. a. Sn(s) + Pb2+(aq) ! Sn2+(aq) +Pb(s) E0cell
= +0.01 V
b. H2(g) + Br2(l) ! 2H+(aq) + 2Br– (aq)
E0cell = +1.07 V
53. Lead(II) sulfate and lead dioxide are very
insoluble in sulfuric acid.
54. a.
b.
c.
d.
e.
f.
2.0, 1.0
18.0, 2.0
90, 80
4.9, 39.5
7.07, 4.40
7.3, 41.1
42. a. 1.61 V
b. 0.94 V
Solutions Manual
741
CH21 p.741-743
7/9/04
12:44 PM
Page 742
55. a. oxidation: 6Cl– (l) ! 3Cl2(g) + 6e–
(anode) reduction: 2Al(l) + 6e– ! 2Al(l)
(cathode)
b. overall reaction: 2AlCl3(l) ! 2Al(l) +
3Cl2(g)
c. anode, chlorine gas; cathode, liquid
aluminum
56. If the cell potential for a redox reaction is
positive, the reaction is spontaneous as
written.
57. In each type of cell, oxidation occurs at the
anode and reduction occurs at the cathode.
58. a, e, and f are spontaneous; b, c, and d are
nonspontaneous.
59. a. Zn ! Zn2+ + 2e–
e. Fe ! Fe2+ + 2e–
f. Na ! Na+ + e–
60. a. Zn + Pb2+ ! Zn2+ + Pb
e. Fe + Pb2+ ! Fe2+ + Pb
f. 2Na + Cl2 ! 2Na+ + 2Cl–
61. a. + 0.63 V
e. + 0.21 V
f. + 4.07 V
62. It will be the reaction that has the larger cell
potential, or more readily oxidized or
reduced.
64. a.
b.
c.
d.
Li+
Fe3+
Cu2+
I2
65. Gold belongs near the bottom, below silver,
because it is one of the least active metals.
66. The paste in a dry cell allows for the
movement of electrons but not ions.
Critical Thinking
67. The chemists’ definition focuses on the
electrons that are produced by oxidation at
742
Core Teaching Resources
68. The spoon is being plated with silver.
69. d; the voltage falls steadily.
70. It will not work as a battery.
71. As electrons flow from the anode to the
cathode in the external circuit, anions
must flow from the cathode compartment
to the anode compartment to maintain
neutrality in the electrolytes. Anions cannot
flow through wire made of copper or any
other metal. The cell will not function if the
salt bridge is replaced with a metal wire.
Concept Challenge
72. a. 2AgCl + Ni ! 2Ag + NiCl2; E0cell = +0.47 V
b. 3Cl2 + 2Al ! 2AlCl3; E0cell = +3.02 V
73. Oxidation: 2Cu(impure) + 2H2SO4 !
2Cu2+ + 2H2 + SO42+
Reduction: 2Cu2+ + 2SO42+ + 2H2O !
2Cu(pure) + 2H2SO4 + O2
Overall reaction: 2Cu(impure) + 2H2O !
2Cu(pure) + 2H2 + O2
74. a. The iron electrode is the anode; the
nickel electrode is the cathode.
b. The anode is negative; the cathode is
positive.
c. Anode: Fe(s) ! Fe2+(aq) + 2e–
Cathode: Ni2+(aq) + 2e– ! Ni(s)
d. E0cell = +0.19 V
75. The battery output would not be 12V.
Cumulative Review
76. a. 3, 2, 3, 2, 4
b. 2, 1, 1, 2
c. 3, 6, 5, 1, 3
77. 467 mL
78. a.
b.
c.
d.
SnCl4 • 5H2O
MgSO4 • 7H2O
FePO4 • 4H2O
CaCl2 • 2H2O
79. a. 0.0125g NaCl
b. 101g KNO3
80. Dilute 31 mL 16M HNO3 to 500 mL with
water.
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63. a. possible oxidation reactions at anode:
(i) 2Cl–(aq) ! Cl2(g) + 2e–
(ii) 2H2O(l) ! O2(g) + 4H+(aq) + 4e–
b. possible reduction reactions at cathode:
(i) Na+(aq) + e– ! Na(s)
(ii) 2H2O(l) + 2e– ! H2(g) + 2OH–(aq)
c. (i) Chloride ions are more readily
oxidized to chlorine gas than water
molecules are oxidized to oxygen.
d. (ii) Water molecules are more easily
reduced than sodium ions.
the anode of a voltaic cell; the dictionary
definition is probably based on an
electrolytic cell, whose electrodes are
defined by the battery terminals to which
they are attached.
CH21 p.741-743
7/9/04
12:44 PM
Page 743
81. a. 4.32 ! 102 kJ
b. 2.55 ! 105 cal
c. 2.70 ! 103 J
82. a.
b.
c.
d.
2
–2.78 ! 10 kJ
–7.03 kJ
13 kJ
–27 kJ
83. 267 kJ
84. a. Entropy is a measure of the disorder of a
system.
b. A reaction that occurs naturally.
85. a and c; Keq < 1
86. a.
b.
c.
d.
pH = 8.00
pH = 5.00
pH = 10.00
pH = 5.00
89. a.
b.
c.
d.
e.
f.
+6
–2
+4
+2
0
+4
90. a.
b.
c.
d.
Ca, +2; Cr, +6; O, –2
K, +1; Mn, +7; O, –2
Ca, +2; N, +5; O, –2
Al, +3; O, –2; H +1
91. b; Ca is oxidized, Cl2 is reduced.
d; Ca is oxidized, H is reduced.
92. a. 3, 6, 1, 5, 3
b. 1, 3, 2, 3
93. a.
b.
c.
d.
Cr, +6
I, +5
Mn, +7
Fe, +3
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87. a. [OH–] = 1 ! 10–7M
b. [OH–] = 1 ! 10–10M
c. [OH–] = 1 ! 10–6M
88. a. 2Na(s) + 2H2O(l) " 2NaOH(aq) + H2(g)
b. Ca(s) + 2H2O(l) " Ca(OH)2(aq) + H2(g)
Solutions Manual
743
CH22 p.744-747
7/9/04
12:44 PM
Page 744
HYDROCARBON COMPOUNDS
22
Reviewing Content
37. pentane: CH3CH2CH2CH2CH3
hexane: CH3CH2CH2CH2CH2CH3
38. a. propane
b. octane
c. pentane
39.
46. a.
H H H
b.
48. No; Hexane contains no substituted
groups.
49. a.
CH 2CH 3
b.
c.
CH3 C CH CH3
2-methyl-2-butene
C
C
C
hexane
C
C
C
C
2, 2-dimethylbutane
C
C
C
2-methylpentane
C
C
C
C
C
2, 3-dimethylbutane
C
C C C C C
3-methylpentane
744
CH
CH
CH 2
CH 3
CH 3
CH 3
44. Five structural isomers with the molecular
formula C6H14 exist.
C
CH 3
CH 3
43. CH2 CHCH2CH2CH3
1-pentene
CH3CH CHCH2CH3
2-pentene
CH3
CH 2CH 3
Core Teaching Resources
50. Two different structural formulas are
possible because a benzene ring exhibits
resonance.
51. Catalysts are used during cracking to
produce more short-chain components,
including components that increase the
performance of gasoline.
52. peat, lignite, bituminous coal, anthracite
coal
53. When coal that contains a high
percentage of sulfur burns, the major air
pollutants SO2 and SO3 are by-products.
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propene
trans-2-pentene
4-methyl-1-pentene
3-ethyl-2-methyl-2-pentene
C
CH2CH3
47. No, molecules with at least one
asymmetric carbon have optical isomers.
41. The carbon-carbon bonds are nonpolar
and the carbon-hydrogen bonds are very
weakly polar.
C
CH2CH3
C
3-ethyl-2-pentene
40. a. 2-methylbutane
b. 2,3-dimethylbutane
c. 3-methylhexane
C
C
CH3
H
H H
ethyl
C
H
cis-2-pentene
CH2CH3
C
H C C
C
H
2-methyl-2-pentene
c.
C
C
H
C
CH3
H H H
propyl
H H
C
CH3
CH2CH3
C
CH2CH3
H
H C C C
C
CH3
H
C
trans-2-pentene
H
42. a.
b.
c.
d.
CH3
C
H C
H
methyl
45. a. Accept any isomer with 5 carbons and
12 hydrogens.
b. Accept any isomer with 7 carbons and
16 hydrogens.
CH22 p.744-747
7/9/04
12:44 PM
Page 745
Understanding Concepts
54. a. The di- indicates two methyl groups,
but only one location is given; 2,2dimethlypentane.
b. Alkyl groups on end carbons are part of
the chain; pentane.
c. The chain wasn’t numbered so the
substituent has the lowest possible
number; 2-methylbutane.
d. The methyl group on carbon 4 is part of
the chain; 3-methylpentane
55. a. Ethyne has one triple C–C bond and two
single C–H bonds.
b. All bonds in propane are single bonds.
c. In methylbenzene, there are hybrid
bonds within the ring and single bonds
within substituents and between
substituents and the ring.
H
H
H
H
H
H
H H
H
H
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CH3
(3)
(1)
(5)
(4)
(2)
Critical Thinking
65. The amount of heat per carbon is higher for
methane (–890 kJ/mol of carbon burned)
than for benzene (–545 kJ/mol of carbon
burned). Methane undergoes complete
combustion if sufficient air is present:.
Burning aromatic compounds produces
more soot.
66. see below
68. H2C “ C “ CH2
H
H
69. see below
c. CH3 CH CH3
d.
64. a.
b.
c.
d.
e.
67. Students may infer that the ring structures
in cyclic hydrocarbons produce stronger
van der Waals attractions, which increase
the energy required for vaporization.
56. a. CH C CH3
b.
63. No, the structures are identical; one has
been flipped over.
CH3
CH3 C CH2 CH CH3
CH3
70. A cycloalkane is a saturated cyclic
hydrocarbon. An aromatic hydrocarbon is
any substance in which the bonding is like
that of benzene. Benzene is an unsaturated
aromatic ring, and its apparent double
bonds are stabilized by resonance.
71. a.
57. propane, butane, pentane
58. Meth- implies one carbon atom; ene
implies a double bond, which requires two
carbon atoms.
59. a.
HH
HC CH
b.
HHH
HCC CH
HHH
c. H C C H
d.
HH
HCCH
HCCH
HH
b.
72. b.
CH3
60. 2C8H18 + 25O2 ! 16CO2 + 18H2O
61. The middle structure is most stable due to
resonance within the ring.
62. a. 9.6 billion
b. 81%
c. CH3—C=C—CH2—CH3
d. CH2=CH—CH2—CH3
73. Alkanes contain only single bonds. Alkenes
contain at least one double bond. Aromatic
Solutions Manual
745
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Page 746
hydrocarbons contain a benzene ring or a
similar ring. Cycloalkanes contain aliphatic
chains linked end-to-end.
74. Gemoetric isomers differ in the
arrangement of substituent groups
attached to each carbon in a double bond.
In optical isomers, there is at least one
asymmetric carbon.
75. The boiling point of undecane is 196° C.
Boiling point (°C) Alkanes
82. 1.67 ! 102 J
83. 1 cal = 4.184 J; 4.184 ! 103 J
84. a. Smaller particle size speeds up the
reaction.
b. Higher temperature usually speeds up
the reaction.
85. a. favors reactants
b. favors products
Concept Challenge
200
[ICl]2
86. a. Keq = [I ][Cl ]
2
2
[H2][Br2]
b. Keq = [HBr]2
100
0
-100
-200
81. 1.13 mol KNO3; 1.14 ! 102 g KNO3
1
2
3
4 5 6 7 8
Number of carbons
9 10
76. Answers will vary.
[HCl]4[S]3[SO2]
c. Keq = [S Cl ]2[H O]2
2 2
2
[NH3]2
d. Keq = [N ][H ]2
2
2
77. a. C6 = 5, C7 = 9, C8 = 18, C9 = 35, C10 = 75
b. As the size of the alkane molecule gets
larger, the number of ways that the
carbon atoms can be bonded together
(structural isomers) increases
dramatically.
87. a.
b.
c.
d.
78. a.
89. a.
b.
c.
d.
—
CH3
3-methylhexane
b.
CH2CH3
CH2CH3
c.
—
—
CH3CH2CH3
—
CH3CH2—C— CHCH2CH2CH2CH3
CH3
3,3-dimethyl-4-ethyloctane
Cumulative Review
79. a. 13.9 L
b. 1 L
c. 20 kPa
80. 3.04 ! 102 calories
746
Core Teaching Resources
88. a. ~8
b. Use a pH meter
H3PO4
CsOH
H2CO3
Be(OH)2
90. a. NaOH " Na+ + OH–
b. Ba(OH)2 " Ba2+ + 2OH–
91. a.
b.
c.
d.
Ca, +2; C, +4; O, –2
Cl, 0
Li, +1; I, +5; O, –2
Na, +1; S, +4; O, –2
92. a.
b.
c.
d.
reduction
reduction
reduction
oxidation
93. a.
b.
c.
d.
e.
f.
+4
+4
+3
+5
+5
+2
94. a. 2, 9, 6, 8
b. 3, 2, 1, 3
© Pearson Education, Inc., publishing as Pearson Prentice Hall. All rights reserved.
CH3CH2CHCH2CH2CH3
10.00
7.59
12.00
11.70
CH22 p.744-747
7/9/04
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Page 747
95. It is the cell potential when the ion
concentrations in the half-cells are 1M, the
temperature is 25°C, and the pressure of
any gases present is 101.3 kPa.
96. Reduction occurs in the half-cell with the
more positive, or less negative, reduction
potential. Ni2+ is reduced and Al is oxidized.
Cell reaction: 3Ni2+(aq) + 2Al(s) ! 3Ni(s) +
2Al+3(aq); Eocell = +1.66 V
97. The reaction is nonspontaneous.
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98. reduction; reduction
Solutions Manual
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CH23 p.748-750
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Page 748
FUNCTIONAL GROUPS
23
Reviewing Content
34. a.
b.
c.
d.
26. a carbon chain or ring
27. a.
Cl
ClCH 2CCH2 CH3
35. a.
b.
c.
d.
propanone or acetone
3-methylbutanal
2-phenylethanal
diphenylmethanone or diphenyl
ketone or benzophenone
e. ethanal or acetaldehyde
f. 3-hexanone or ethylpropylketone
Cl
b.
Br
Br
c.
Br
Cl
Cl
36. The properties of polyethylene vary with
the length of the chains.
28. a. 3-chloropropene
b. 1,2-dichloro-4-methylpentane
c. 1,3-dibromobenzene
29. a.
37. a.
CH
CH2
CH3
CH3
CH2
CH2
1, 1-dichloropropane
Cl
CH
CH2
Br
CH3
CH3
CH2
CH2
CH3
CH
38. a.
R
b.
X
C
CH3
Br
2-bromo-2-methylpropane
Cl
C
O
R
40. a.
OH
c.
C
CH
CH3
32. a.
H H
I
CH3CHCHCH3
CH2CHCH2CH3
c.
I
d.
Cl
CH3CHCHCH3
Cl
33. a.
H
Br
CH2
CH2
b.
bromoethane
c.
H
OH
CH2
CH2
H
Cl
CH2
CH2
d.
chloroethane
748
Cl
CH2
1, 2-dichloroethane
ethanol
e.
Cl
CH2
Core Teaching Resources
H
H
CH2
CH2
ethane
R
C
O!Na"! CH3CH2OH
O
CH3
Br
b.
Br Br
N
O
c.
OH
O H
OCH3 ! H2O
CH3CH2CH2
OH
d.
CH3
C
O
CH3
b.
b.
R
R
39. b. CH3CH2OH (46) has the highest boiling
point.
2, 2-dichloropropane
30. a.
C
d.
O
R
O
R
C
H
41. Both atoms in a carbon-carbon double
bond have the same electronegativity, so
the bond is nonpolar. Because oxygen is
more electronegative than carbon, a
carbon-oxygen bond is very polar.
42. a. HCOOH + KOH ! HCOO–K+ + H2O
b. CH3CH2COOH + NaOH !
CH3CH2COO–Na+ + H2O
c. CH3COOH + NaOH ! CH3COO–Na+ +
H2O
43. a.
b.
c.
d.
e.
phenol
ether
alcohol
phenol
alcohol
© Pearson Education, Inc., publishing as Pearson Prentice Hall. All rights reserved.
CH3
CH3
c.
CH2
CH3
Cl
C
CH3
1-bromo-2-methylpropane
CH2
1, 3-dichloropropane
CH3
CH
CH3 Br
Cl
CH2
CH
Cl
Understanding Concepts
2-bromobutane
1, 2-dichloropropane
Cl
CH
Cl
CH3
1-bromobutane
Cl
b.
CH
Br
Cl
CH2
CH2
CH2
b.
Cl
methylethyl ether
ethylphenyl ether
divinyl ether or vinyl ether
diisopropyl ether or isopropyl ether
CH23 p.748-750
7/9/04
12:44 PM
44. a.
Cl
b.
Cl
CH3CH2CH
c.
Page 749
Br
Br
CH3CH2CH
CH2
CH2
H
Br
45. a. carboxyl group, ethanoic acid (acetic
acid)
b. ketone (carbonyl group), propanone
(acetone)
c. ether, diethyl ether (ethyl ether)
d. alcohol (hydroxyl group), ethanol (ethyl
alcohol)
46. a.
b.
CH3OH
OH
methanol
CH3
CH
CH3
2-propanol
c.
d.
CH3 H
CH3
CH
C
OH
OH
H
H
cyclohexanol
2-methyl-1-propanol
47. a.
b.
CH3CH2COO–Na+, CH3CH2OH
CH3COO–K+,
CH3CH2COOH, CH3CHCH2OH
© Pearson Education, Inc., publishing as Pearson Prentice Hall. All rights reserved.
Critical Thinking
48. a.
O
b.
H2O
HC1
CH3
C
OH
CH3OH
methyl ethanoate water
ethanoic acid methanol
(methyl acetate)
(acetic acid)
CH3CH2CH2COOCH2CH2CH3
H2O
propyl butanoate
water
NaOH
(propyl butyrate)
O
CH3CH2CH2
C
O Na
sodium butanoate
CH3CH2CH2OH
1-propanol
(sodium butyrate)
c.
HCOOCH2CH3
H2O
KOH
ethyl methanoate water
(ethyl formate)
O
H
C
52. Acetaldehyde is polarized by its carbonyl
oxygen forming stronger intermolecular
attractions. Nonpolar propane has weak
intermolecular attractions. Thus, propane
molecules are more easily liberated from
the liquid state.
54. Substitution of an alkane by a halogen, for
example, usually gives a mixture of
products. Addition to a double bond or a
triple can give a single addition product.
CH3
CH3COOCH3
51. The alcohol molecules form hydrogen
bonds with one another, resulting in a
higher boiling point. They also form
hydrogen bonds with water molecules,
causing 1-butanol to be more soluble than
diethyl ether. (Although diethyl ether is
polar, 1-butanol has greater polarity.)
53. The short-chain ethanoic acid has a higher
water solubility.
OH
c.
50. The oxygen atom in diethyl ether polarizes
the small molecule. This enables diethyl
ether to dissolve in water, which is also
polar. The large dihexyl ether molecule has
large nonpolar parts and does not dissolve.
Propane is less soluble in water than is
diethyl ether because propane is nonpolar.
O K
CH3CH2OH
potassium methanoate
ethanol
(potassium formate)
49. The chemical properties (and toxicity) of
organic compounds are determined by the
compound as a whole. As a substituent in a
molecule, a phenyl group ring does not
have the same properties as benzene.
55. H2NCH2(CH2)3CH2NH2 cadaverine;
H2NCH2(CH2)4CH2NH2 putrescine; both
compounds are amines.
56. (Note: 23b has been eliminated because the
chapter SE doesn't give a reaction that
would allow students to write a chemical
equation for producing methane
(degradation of organic compounds in
Earth, reduction of methanol, etc.). So, 23 c
in approved SE pages becomes 23b.)
a. CH4 + Cl2
UV
Light
b. C2H4 + H2
Pt
CH3Cl + HCl
C2H6
Concept Challenge
57. Cholesterol is an alcohol with a hydroxyl
group on a cycloalkane. It has four
nonaromatic rings. It has a double bond on
one of its rings, as well as a large alkyl
group, making it nonpolar.
58. CH2CH2(g) + Br2(l) ! CH2BrCH2Br(l)
CH2BrCH2Br(l) + 2NaOH(aq) !
CH2OHCH2OH(l) + 2NaBr(aq)
Solutions Manual
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Page 750
59. Waving lotion reduces —S—S— bonds to —
SH bonds. Hair can be placed in curlers to
form the hair in the desired shape. The
neutralizing agent is an oxidizing agent that
reforms —S—S— bonds, locking the hair
into its curly shape. Similar steps could be
used to straighten curly hair.
60. CF2=CF2
Cumulative Review
61. b. 3
62. a.
F !!!
F
!
b. H ! O !!!
( O H)!
71. a, c, d, b
72. a.
b.
c.
d.
e.
Na +1; N +3; O –2
Co +2; S +6; O –2
Se +2; O –2
Zn +2; O –2; H +1
K +1; Pt +2; Cl –1
73. Oxidized: H of BH4 Reduced: H of H2O
unaffected: Na, B, O
74. spontaneous redox reactions
75. Reduction always occurs at the cathode. In
the electrolytic cell, the cathode is the
negative electrode.
76. a.
CH3
63. 2.86 g SO2
64. 1.15 ! 102 kPa
CH3
b.
CH3
—
65. Anhydrous Na2CO3(s) is the better value;
the decahydrate is 63.0% water.
66. The amount of dissolved oxygen is greater
entering the plant; solubilities of gases tend
to decrease with increasing temperature.
c. CH3CH
67. 0.117M Ca(NO3)2
d. HC
69. 71 kJ
70. a.
b.
c.
d.
750
shift toward products
shift toward reactants
shift toward reactants
shift toward products
Core Teaching Resources
CHCH2CH3
CHCH3
CCH2CH2CH3
77. coal
78. a. 5 bonds to carbons making up the
double bond
b. 5 bonds to center carbon
c. correct structure
d. only 3 bonds to CH carbon not in
double bond
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68. At any given moment, the rate of dissolving
of solute is equal to the rate of precipitation
of solute. As a result, the concentration of
the solution remains constant.
CH3C