Chemistry in focus a molecular nivaldo j tro c

Periodic Table of the Elements
G

1

H

8A

Hydrogen
1.008
2

1A
3

S

S

4

Li

Be

Lithium
6.941

Beryllium
9.012

11

S

12

Na

Mg
Magnesium
24.31
S

Atomic number
Symbol

G

92

U
Uranium
238.03

Atomic weight

Solid
Liquid
Gas

Not found
in nature

S

20

3A

Metals
Transition metals,
lanthanide series,
actinide series

5

Metalloids
Nonmetals,
noble gases

S

Sodium
22.99
19

State: S
L
G
X

2A

3B
S

21

4B
22

S

6B

5B
23

S

24

S

7B
25

S

8B

9

8
S

26

S

27

10
S

28

11B
S

29

S

30

6

S

5A

7

G

6A

8

G

7A

9

G

10

B

C

N

O

F

Ne

Carbon
12.01

Nitrogen
14.01

Oxygen
16.00

Fluorine
19.00

Neon
20.18

S

14

S

S

15

S

16

17

G

18

Al

Si

P

S

Cl

Ar

Aluminum
26.98

Silicon
28.09

Phosphorus
30.97

Sulfur
32.06

Chlorine
35.45

Argon
39.95

31

S

32

S

S

33

S

34

35

L

1

Helium
4.003

Boron
10.81
13

12B

S

4A

G

He

36

G

2
G

3
G

K

Ca

Sc

Ti

V

Cr

Mn

Fe

Co

Ni

Cu

Zn

Ga

Ge

As

Se

Br

Kr

Potassium
39.10

Calcium
40.08

Scandium
44.96

Titanium
47.90

Vanadium
50.94

Chromium
52.00

Manganese
54.94

Iron
55.85

Cobalt
58.93

Nickel

Copper
63.55

Zinc
65.38

Gallium
69.72

Germanium
72.59

Arsenic
74.92

Selenium
78.96

Bromine
79.90

Krypton
83.80

S

S

X

37

S

S

38

S

39

40

S

41

Rb

Sr

Y

Zr

Nb

Rubidium
85.47

Strontium
87.62

Yttrium
88.91

Zirconium
91.22

Niobium
92.91

55

S

56

S

57

S

72

S

73

42

Mo

43

Tc

Molybdenum Technetium
95.94
(98)

S

74

S

75

S

S

44

58.71
S

45

S

46

S

47

S

48

49

S

50

S

S

51

S

52

53

S

54

Ru

Rh

Pd

Ag

Cd

In

Sn

Sb

Te

I

Xe

Rhodium
102.91

Palladium
106.4

Silver
107.87

Cadmium
112.40

Indium
114.82

Tin
118.69

Antimony
121.75

Tellurium

Iodine
126.90

Xenon
131.30

S

76

S

77

S

78

S

79

80

L

81

S

82

S

S

83

127.60

84

S

85

S

86

Cs

Ba

La

Hf

Ta

W

Re

Os

Ir

Pt

Au

Hg

Tl

Pb

Bi

Po

At

Rn

Barium
137.34

Lanthanum
138.91

Hafnium
178.49

Tantalum
180.95

Tungsten
183.85

Rhenium
186.21

Osmium
190.2

Iridium
192.22

Platinum
195.09

Gold
196.97

Mercury
200.59

Thallium
204.37

Lead
207.2

Bismuth
208.96

Polonium
(209)

Astatine
(210)

Radon
(222)

S

88

S

89

S

104

X

105

X

106

X

107

X

108

X

Fr

Ra

Ac

Rf

Db

Sg

Bh

Hs

Francium
(223)

Radium
226.03

Actinium

(227)

Rutherfordium
(261)

Dubium
(262)

Seaborgium
(266)

Bohrium
(264)

Hassium
(265)

58

S

Ce
Cerium
140.12
90

59

S

Pr

60

S

Nd

61

91

S

92

93

X

Mt

X

Pm
S

109

110

X

Ds

111

X

Rg

112

X

X

62

S

63

S

64

S

S

65

113

X

Uut

Uub

Meitnerium Darmstadtium Roentgenium Ununbium
(271)
(272)
(277)
(268)

Praseodymium Neodymium Promethium
140.91
144.24
(145)
S

G

Ruthenium
101.07

Cesium
132.91

87

4

114

X

Uuq

115

X

Uup

116

5
G

6

X

Uuh

7

Ununtrium Ununquadium Ununpentium Ununhexium

289
288
292
284

66

S

67

S

S

68

S

69

70

S

71

S

Sm

Eu

Gd

Tb

Dy

Ho

Er

Tm

Yb

Lu

Samarium
150.4

Europium
151.96

Gadolinium
157.25

Terbium

Dysprosium
162.50

Holmium
164.93

Erbium
167.26

Thulium
168.93

Ytterbium
173.04

Lutetium
174.97

94

X

95

X

96

X

158.93
97

X

Th

Pa

U

Np

Pu

Am

Cm

Bk

Thorium
232.04

Protactinium
231.04

Uranium
238.03

Neptunium
237.05

Plutonium
(244)

Americium
(243)

Curium
(247)

Berkelium
(247)

98

Cf

X

99

X

Es

Californium Einsteinium
(251)
(254)

100

X

Fm
Fermium
(257)

101

Md

X

102

X

No

Mendelevium Nobelium
(258)
(259)

103

S

Lr

Lawrencium
(260)


Chemistry
in Focus
A MOLECULAR VIEW OF OUR WORLD
THIRD EDITION

Nivaldo J. Tro
Westmont College
With special contributions by

Don Neu
St. Cloud State University

Australia • Brazil • Japan • Korea • Mexico • Singapore • Spain • United Kingdom • United States


Chemistry in Focus: A Molecular View of
Our World, Fourth Edition
Nivaldo J. Tro
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1 2 3 4 5 6 7 12 11 10 09


To Annie


About the Author
Nivaldo J. Tro received his BA degree from Westmont College
and his PhD degree from Stanford University. He went on to a

post-doctoral research position at the University of California at
Berkeley. In 1990, he joined the chemistry faculty at Westmont
College in Santa Barbara, California. Professor Tro has been
honored as Westmont’s outstanding teacher of the year three
times (1994, 2001, and 2008). He was named Westmont’s
outstanding researcher of the year in 1996. Professor Tro lives in
the foothills of Santa Barbara with his wife, Ann, and their four
Nivaldo Tro

children, Michael, Alicia, Kyle, and Kaden. In his leisure time,
Professor Tro likes to spend time with his family in the outdoors.
He enjoys running, biking, surfing, and snowboarding.


Brief Contents
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15

16
17
18
19

Molecular Reasons 2
The Chemist’s Toolbox 28
Atoms and Elements 54
Molecules, Compounds, and Chemical Reactions 88
Chemical Bonding 116
Organic Chemistry 146
Light and Color 186
Nuclear Chemistry 212
Energy for Today 242
Energy for Tomorrow: Solar and Other Renewable Energy Sources 276
The Air Around Us 298
The Liquids and Solids Around Us: Especially Water 328
Acids and Bases: The Molecules Responsible for Sour and Bitter 360
Oxidation and Reduction 382
The Chemistry of Household Products 402
Biochemistry and Biotechnology 432
Drugs and Medicine: Healing, Helping, and Hurting 476
The Chemistry of Food 510
Nanotechnology 542

Appendix 1: Significant Figures A-1
Appendix 2: Answers to Selected Exercises A-5
Appendix 3: Answers to Your Turn Questions A-31
Glossary G-1
Index I-1

v


Contents
CHAPTER 1
MOLECULAR THINKING
Why Should Nonscience Majors Study
Science? 5

WHAT IF. . .
Observation and Reason 10

THE MOLECULAR REVOLUTION
Seeing Atoms 21

Molecular Reasons
1.1
1.2
1.3
1.4
1.5
1.6
1.7
1.8
1.9
1.10

2

Firesticks 4

Molecular Reasons 5
The Scientist and the Artist 6
The First People to Wonder About Molecular Reasons
Immortality and Endless Riches 9
The Beginning of Modern Science 10
The Classification of Matter 11
The Properties of Matter 15
The Development of the Atomic Theory 16
The Nuclear Atom 18

9

CHAPTER SUMMARY 22
CHEMISTRY ON THE WEB 23
KEY TERMS 23
EXERCISES 23
FEATURE PROBLEMS AND PROJECTS 26

CHAPTER 2
MOLECULAR THINKING
Feynman’s Ants 31

THE MOLECULAR REVOLUTION
Measuring Average Global
Temperatures 33

The Chemist’s Toolbox
2.1
2.2
2.3

2.4
2.5
2.6
2.7
2.8

Curious About Oranges 30
Measurement 31
Scientific Notation 33
Units in Measurement 35
Converting Between Units 38
Reading Graphs 40
Problem Solving 44
Density: A Measure of Compactness
CHAPTER SUMMARY 49
CHEMISTRY ON THE WEB 49
KEY TERMS 49
EXERCISES 50
FEATURE PROBLEMS AND PROJECTS 52

vi

28

46


Contents

CHAPTER 3

WHAT IF. . .
Complexity Out of Simplicity 65

WHAT IF. . .
Philosophy, Determinism, and Quantum
Mechanics 72

THE MOLECULAR REVOLUTION
The Reactivity of Chlorine and the
Depletion of the Ozone Layer 73

MOLECULAR THINKING

Atoms and Elements
3.1
3.2
3.3
3.4
3.5
3.6
3.7
3.8
3.9
3.10
3.11

Is Breathing Helium Dangerous? 74

vii

54

A Walk on the Beach 56
Protons Determine the Element 58
Electrons 60
Neutrons 62
Specifying an Atom 63
Atomic Mass 64
Periodic Law 66
A Theory That Explains the Periodic Law: The Bohr Model
The Quantum Mechanical Model for the Atom 71
Families of Elements 73
A Dozen Nails and a Mole of Atoms 76

67

CHAPTER SUMMARY 80
CHEMISTRY ON THE WEB 81
KEY TERMS 81
EXERCISES 81
FEATURE PROBLEMS AND PROJECTS 85

CHAPTER 4

WHAT IF. . .
Problem Molecules 95

MOLECULAR FOCUS
Calcium Carbonate 97

THE MOLECULAR REVOLUTION
Engineering Animals to Do
Chemistry 107

Molecules, Compounds,
and Chemical Reactions
4.1
4.2
4.3
4.4
4.5
4.6
4.7
4.8

88

Molecules Cause the Behavior of Matter 90
Chemical Compounds and Chemical Formulas 90
Ionic and Molecular Compounds 92
Naming Compounds 96
Formula Mass and Molar Mass of Compounds 99
Composition of Compounds: Chemical Formulas as Conversion Factors 101
Forming and Transforming Compounds: Chemical Reactions 103
Reaction Stoichiometry: Chemical Equations as Conversion Factors 106
CHAPTER SUMMARY 111

MOLECULAR THINKING

CHEMISTRY ON THE WEB 112

Campfires 110

KEY TERMS 112
EXERCISES 112
FEATURE PROBLEMS AND PROJECTS 115

CHAPTER 5
MOLECULAR THINKING
Fluoride 121

Chemical Bonding
5.1
5.2
5.3
5.4

From Poison to Seasoning 118
Chemical Bonding and Professor G. N. Lewis
Ionic Lewis Structures 121
Covalent Lewis Structures 123

116
119


viii

Contents

MOLECULAR FOCUS
Ammonia 129

THE MOLECULAR REVOLUTION

5.5
5.6
5.7

Chemical Bonding in Ozone 129
The Shapes of Molecules 131
Water: Polar Bonds and Polar Molecules

135

CHAPTER SUMMARY 141

AIDS Drugs 136

CHEMISTRY ON THE WEB 141
KEY TERMS 142
EXERCISES 142
FEATURE PROBLEMS AND PROJECTS 145

CHAPTER 6
THE MOLECULAR REVOLUTION
The Origin of Life 150

THE MOLECULAR REVOLUTION
Determining Organic Chemical

Structures 166

WHAT IF. . .
Alcohol and Society 172

MOLECULAR FOCUS
Carvone 174

MOLECULAR THINKING
What Happens When We Smell
Something 180

Organic Chemistry
6.1
6.2
6.3
6.4
6.5
6.6
6.7
6.8
6.9
6.10
6.11
6.12
6.13
6.14

146

Carbon 148
A Vital Force 149
The Simplest Organic Compounds: Hydrocarbons 151
Isomers 160
Naming Hydrocarbons 162
Aromatic Hydrocarbons and Kekule’s Dream 165
Functionalized Hydrocarbons 168
Chlorinated Hydrocarbons: Pesticides and Solvents 169
Alcohols: To Drink and to Disinfect 170
Aldehydes and Ketones: Smoke and Raspberries 172
Carboxylic Acids: Vinegar and Bee Stings 175
Esters and Ethers: Fruits and Anesthesia 176
Amines: The Smell of Rotten Fish 178
A Look at a Label 179
CHAPTER SUMMARY 181
CHEMISTRY ON THE WEB 181
KEY TERMS 182
EXERCISES 182
FEATURE PROBLEMS AND PROJECTS 185

CHAPTER 7
MOLECULAR THINKING
Changing Colors 190

WHAT IF. . .
X-Rays—Dangerous or Helpful? 195

WHAT IF. . .
The Cost of Technology 201

WHAT IF. . .
The Mind–Body Problem 202

Light and Color
7.1
7.2
7.3
7.4
7.5
7.6
7.7
7.8

A New England Fall 188
Light 190
The Electromagnetic Spectrum 193
Excited Electrons 196
Identifying Molecules and Atoms with Light 198
Magnetic Resonance Imaging: Spectroscopy of the Human Body
Lasers 202
Lasers in Medicine 204

THE MOLECULAR REVOLUTION

CHAPTER SUMMARY 207

Watching Molecules Dance 205

CHEMISTRY ON THE WEB 208

186

199


Contents

MOLECULAR FOCUS

KEY TERMS 208

Retinal 206

EXERCISES 209

ix

FEATURE PROBLEMS AND PROJECTS 211

CHAPTER 8
WHAT IF. . .
The Ethics of Science 226

THE MOLECULAR REVOLUTION
Fusion Research 230

MOLECULAR THINKING
Radiation and Smoke Detectors 233

WHAT IF. . .

Radiation—Killer or Healer? 237

Nuclear Chemistry
8.1
8.2
8.3
8.4
8.5
8.6
8.7
8.8
8.9
8.10
8.11
8.12
8.13

212

A Tragedy 214
An Accidental Discovery 214
Radioactivity 216
Half-Life 219
Nuclear Fission 222
The Manhattan Project 224
Nuclear Power 226
Mass Defect and Nuclear Binding Energy 229
Fusion 230
The Effect of Radiation on Human Life 231
Carbon Dating and the Shroud of Turin 234

Uranium and the Age of the Earth 236
Nuclear Medicine 237
CHAPTER SUMMARY 238
CHEMISTRY ON THE WEB 239
KEY TERMS 239
EXERCISES 239
FEATURE PROBLEMS AND PROJECTS 241

CHAPTER 9
MOLECULAR THINKING
Campfire Smoke 259

MOLECULAR FOCUS
Sulfur Dioxide 263

MOLECULAR THINKING
Are Some Fossil Fuels Better Than
Others? 267

THE MOLECULAR REVOLUTION
Taking Carbon Captive 268

Energy for Today
9.1
9.2
9.3

Molecules in Motion 244
Our Absolute Reliance on Energy 244
Energy and Its Transformations: You Cannot Get Something

for Nothing 247
9.4 Nature’s Heat Tax: Energy Must Be Dispersed 249
9.5 Units of Energy 251
9.6 Temperature and Heat Capacity 254
9.7 Chemistry and Energy 256
9.8 Energy for Our Society 257
9.9 Electricity from Fossil Fuels 260
9.10 Smog 261
9.11 Acid Rain 263
9.12 Environmental Problems Associated with Fossil-Fuel Use:
Global Warming 264
CHAPTER SUMMARY 270
CHEMISTRY ON THE WEB 270

242


x

Contents

KEY TERMS 271
EXERCISES 271
FEATURE PROBLEMS AND PROJECTS 274

CHAPTER 10

MOLECULAR FOCUS
Hydrogen 286

WHAT IF. . .
Legislating Renewable Energy 287

THE MOLECULAR REVOLUTION
Fuel Cell and Hybrid Electric
Vehicles 292

WHAT IF. . .
Future Energy Scenarios 292

Energy for Tomorrow: Solar and Other
Renewable Energy Sources
10.1
10.2
10.3
10.4
10.5
10.6
10.7
10.8
10.9
10.10
10.11

276

Earth’s Ultimate Energy Source: The Sun 278
Hydroelectric Power: The World’s Most Used Solar Energy Source 278
Wind Power 280
Solar Thermal Energy: Focusing and Storing the Sun 280

Photovoltaic Energy: From Light to Electricity with No Moving Parts 283
Energy Storage: The Plague of Solar Sources 285
Biomass: Energy from Plants 286
Geothermal Power 288
Nuclear Power 288
Efficiency and Conservation 289
2050 World: A Speculative Glimpse into the Future 290
CHAPTER SUMMARY 293
CHEMISTRY ON THE WEB 294
KEY TERMS 294
EXERCISES 295
FEATURE PROBLEMS AND PROJECTS 297

CHAPTER 11
MOLECULAR THINKING
Drinking from a Straw 304

MOLECULAR FOCUS
Ozone 318

THE MOLECULAR REVOLUTION
Measuring Ozone 318

The Air Around Us
11.1
11.2
11.3
11.4
11.5
11.6

11.7
11.8
11.9
11.10
11.11

298

Air Bags 300
A Gas Is a Swarm of Particles 301
Pressure 301
The Relationships Between Gas Properties 304
The Atmosphere: What Is in It? 308
The Atmosphere: A Layered Structure 310
Air Pollution: An Environmental Problem in the Troposphere 312
Cleaning Up Air Pollution: The Clean Air Act 313
Ozone Depletion: An Environmental Problem in the Stratosphere 316
The Montreal Protocol: The End of Chlorofluorocarbons 320
Myths Concerning Ozone Depletion 321
CHAPTER SUMMARY 323
CHEMISTRY ON THE WEB 323
KEY TERMS 324
EXERCISES 324
FEATURE PROBLEMS AND PROJECTS 326


Contents

CHAPTER 12

MOLECULAR THINKING
Making Ice Cream 332

MOLECULAR THINKING
Soap—A Molecular Liaison 338

MOLECULAR THINKING
Flat Gasoline 342

MOLECULAR FOCUS
Trichloroethylene (TCE) 350

WHAT IF. . .
Criticizing the EPA 353

The Liquids and Solids Around Us:
Especially Water
12.1
12.2
12.3
12.4
12.5
12.6
12.7
12.8
12.9
12.10
12.11
12.12
12.13

12.14
12.15

No Gravity, No Spills 330
Liquids and Solids 331
Separating Molecules: Melting and Boiling 332
The Forces That Hold Us—and Everything Else—Together
Smelling Molecules: The Chemistry of Perfume 339
Chemists Have Solutions 341
Water: An Oddity Among Molecules 343
Water: Where Is It and How Did It Get There? 345
Water: Pure or Polluted? 345
Hard Water: Good for Our Health, Bad for Our Pipes 346
Biological Contaminants 348
Chemical Contaminants 348
Ensuring Good Water Quality: The Safe Drinking Water Act
Public Water Treatment 352
Home Water Treatment 354

xi

328

334

351

CHAPTER SUMMARY 356
CHEMISTRY ON THE WEB 356
KEY TERMS 357

EXERCISES 357
FEATURE PROBLEMS AND PROJECTS 359

CHAPTER 13

MOLECULAR FOCUS
Cocaine 365

MOLECULAR THINKING
Bee Stings and Baking Soda 372

WHAT IF. . .
Practical Environmental
Protection 377

THE MOLECULAR REVOLUTION
Neutralizing the Effects
of Acid Rain 377

Acids and Bases: The Molecules Responsible
for Sour and Bitter
13.1
13.2
13.3
13.4
13.5
13.6
13.7
13.8
13.9

13.10
13.11

If It Is Sour, It Is Probably an Acid 362
The Properties of Acids: Tasting Sour and Dissolving Metals 362
The Properties of Bases: Tasting Bitter and Feeling Slippery 363
Acids and Bases: Molecular Definitions 365
Strong and Weak Acids and Bases 367
Specifying the Concentration of Acids and Bases: The pH Scale 368
Some Common Acids 369
Some Common Bases 372
Acid Rain: Extra Acidity from the Combustion of Fossil Fuels 374
Acid Rain: The Effects 375
Cleaning Up Acid Rain: The Clean Air Act Amendments of 1990 376
CHAPTER SUMMARY 378
CHEMISTRY ON THE WEB 378
KEY TERMS 379
EXERCISES 379
FEATURE PROBLEMS AND PROJECTS 381

360


xii

Contents

CHAPTER 14
MOLECULAR THINKING
The Dulling of Automobile

Paint 387

MOLECULAR FOCUS
Hydrogen Peroxide 388

THE MOLECULAR REVOLUTION
Fuel Cell Vehicles 395

Oxidation and Reduction
14.1
14.2
14.3
14.4
14.5
14.6
14.7
14.8

382

Rust 384
Oxidation and Reduction: Some Definitions 384
Some Common Oxidizing and Reducing Agents 388
Respiration and Photosynthesis 389
Batteries: Making Electricity with Chemistry 389
Fuel Cells 393
Corrosion: The Chemistry of Rust 395
Oxidation, Aging, and Antioxidants 397
CHAPTER SUMMARY 398

WHAT IF. . .

CHEMISTRY ON THE WEB 398

The Economics of New Technologies
and Corporate Handouts 396

KEY TERMS 399
EXERCISES 399
FEATURE PROBLEMS AND PROJECTS 401

CHAPTER 15

MOLECULAR FOCUS
Polyoxyethylene 409

MOLECULAR THINKING
Weather, Furnaces,
and Dry Skin 413

WHAT IF. . .
Consumer Chemistry
and Consumerism 418

THE MOLECULAR REVOLUTION
Conducting Polymers 423

The Chemistry of Household
Products

402

15.1
15.2
15.3
15.4
15.5
15.6
15.7
15.8
15.9

Cleaning Clothes with Molecules 404
Soap: A Surfactant 405
Synthetic Detergents: Surfactants for Hard Water 407
Laundry-Cleaning Formulations 409
Corrosive Cleaners 410
Hair Products 411
Skin Products 412
Facial Cosmetics 414
Perfumes and Deodorants: Producing Pleasant Odors
and Eliminating Unpleasant Ones 415
15.10 Polymers and Plastics 419
15.11 Copolymers: Nylon, Polyethylene Terephthalate, and Polycarbonate
15.12 Rubber 424

423

CHAPTER SUMMARY 426
CHEMISTRY ON THE WEB 427

KEY TERMS 427
EXERCISES 428
FEATURE PROBLEMS AND PROJECTS 430

CHAPTER 16
MOLECULAR FOCUS
Raffinose 446

Biochemistry and Biotechnology
16.1
16.2
16.3

Brown Hair, Blue Eyes, and Big Mice 434
Lipids and Fats 434
Carbohydrates: Sugar, Starch, and Sawdust

432
440


xiii

Contents

MOLECULAR THINKING
Wool 455

THE MOLECULAR REVOLUTION
The Human Genome Project 464

WHAT IF. . .

16.4
16.5
16.6
16.7
16.8
16.9

Proteins: More Than Muscle 446
Protein Structure 451
Some Common Proteins 454
Nucleic Acids: The Blueprint for Proteins
Recombinant DNA Technology 462
Cloning 465

456

CHAPTER SUMMARY 468

The Ethics of Therapeutic Cloning
and Stem Cell Research 467

CHEMISTRY ON THE WEB 469
KEY TERMS 469
EXERCISES 469
FEATURE PROBLEMS AND PROJECTS 475

CHAPTER 17

MOLECULAR THINKING
Generic or Name Brands? 482

MOLECULAR FOCUS
Azidothymidine (AZT) 485

WHAT IF. . .
The Controversy of Abortion 487

WHAT IF. . .
Alcoholism 491

WHAT IF. . .
The Danger of Street Drugs 496

WHAT IF. . .

Drugs and Medicine: Healing, Helping,
and Hurting
17.1
17.2
17.3
17.4
17.5
17.6
17.7
17.8
17.9
17.10

17.11
17.12
17.13
17.14

476

Love and Depression 478
Relieving Pain, Reducing Fever, and Lowering Inflammation 478
Killing Microscopic Bugs: Antibiotics 480
Antiviral Drugs and Acquired Immune Deficiency Syndrome 482
Sex Hormones and the Pill 486
Steroids 487
Chemicals to Fight Cancer 488
Depressants: Drugs That Dull the Mind 490
Narcotics: Drugs That Diminish Pain 493
Stimulants: Cocaine and Amphetamine 496
Legal Stimulants: Caffeine and Nicotine 498
Hallucinogenic Drugs: Mescaline and Lysergic Acid Diethylamide 499
Marijuana 501
Prozac and Zoloft: SSRIs 502
CHAPTER SUMMARY 505

Prescription Drug Abuse 502

CHEMISTRY ON THE WEB 506

THE MOLECULAR REVOLUTION

KEY TERMS 506

Consciousness 503

EXERCISES 507
FEATURE PROBLEMS AND PROJECTS 508

CHAPTER 18
MOLECULAR THINKING
Sugar Versus Honey 514

THE MOLECULAR REVOLUTION
Does Sugar Make Children
Hyperactive? 516

The Chemistry of Food
18.1
18.2
18.3
18.4
18.5

You Are What You Eat, Literally 512
Carbohydrates: Sugars, Starches, and Fibers 513
Proteins 517
Fats, Oils, and Cholesterol 518
Caloric Intake and the First Law: Extra Calories Lead to Fat

510

521

xiv

Contents

WHAT IF. . .
The Second Law
and Food Energy 518

MOLECULAR FOCUS
Ammonium Nitrate 533

18.6
18.7
18.8
18.9
18.10

Vitamins 524
Minerals 527
Food Additives 530
The Molecules Used to Grow Crops: Fertilizers and Nutrients 533
The Molecules Used to Protect Crops: Insecticides and Herbicides 534
CHAPTER SUMMARY 538

WHAT IF. . .

CHEMISTRY ON THE WEB 538

Pesticide Residues in Food—
A Cause for Concern? 536

KEY TERMS 539
EXERCISES 539
FEATURE PROBLEMS AND PROJECTS 541

CHAPTER 19
Molecular Focus
Buckminsterfullerene 549

What if. . .
Value-Free Science 554

THE MOLECULAR REVOLUTION
The Dark Side of Nanotechnology 556

Nanotechnology
19.1
19.2
19.3
19.4
19.5
19.6
19.7
19.8
19.9

542

Extreme Miniaturization 544
Really Small: What’s the Big Deal? 545
Scanning Tunneling Microscope 547
Atomic Force Microscope 548
Buckyballs—A New Form of Carbon 548
Carbon Nanotubes 550
Nanomedicine 552
Today’s Nanoproducts 554
Nanoproblems 555
CHAPTER SUMMARY 557
CHEMISTRY ON THE WEB 557
EXERCISES 558
FEATURE PROBLEMS AND PROJECTS 559

Appendix 1: Significant Figures

A-1

Appendix 2: Answers to Selected Exercises
Appendix 3: Answers to Your Turn Questions
Glossary
Index

G-1
I-1

A-5
A-31

Preface
To the Instructor
Chemistry in Focus is a text designed for a one-semester college chemistry course for students not majoring in the sciences.
This book has two main goals: the first is to develop in students an appreciation for the molecular world and the fundamental role it plays in daily life; the second is to develop in
students an understanding of the major scientific and technological issues affecting our society.

The two main goals of this book are for
students to understand the molecular
world and to understand the scientific
issues that face society.

A MOLECULAR FOCUS

PhotoDisc

The first goal is essential. Students should leave this course understanding that
the world is composed of atoms and molecules and that everyday processes—
water boiling, pencils writing, soap cleaning—are caused by atoms and molecules.
After taking this course, a student should look at water droplets, salt crystals, and
even the paper and ink of their texts in a different way. They should know, for
example, that beneath the surface of a water droplet or a grain of salt lie profound reasons for each of their properties. From the opening example to the closing chapter, this text maintains this theme through a consistent focus on explaining the macroscopic world in terms of the molecular world.
The art program, a unique component of this text, emphasizes the connection
between what we see—the macroscopic world—and what we cannot see—the molecular world. Throughout the text, photographs of everyday objects or processes are
magnified to show the molecules and atoms responsible for them.
The molecules within these magnifications are depicted using
space-filling models to help students develop the most accurate
picture of the molecular world. Similarly, many molecular formulas are portrayed not only with structural formulas but with spacefilling drawings as well. Students are not meant to understand
every detail of these formulas—since they are not scientists, they
do not need to—rather, they should begin to appreciate the beauty
and form of the molecular world. Such an appreciation will enrich

their lives as it has enriched the lives of those of us who have
chosen science and science education as our career paths.

Ϫ
ϩ

Ϫ

ϩ
Ϫ

ϩ
Ϫ
Ϫ

C H E M I S T R Y I N A S O C I E TA L A N D
E N V I R O N M E N TA L C O N T E X T
The other primary goal of this text is to develop in students an
understanding of the scientific, technological, and environmental issues facing them
as citizens and consumers. They should leave this course with an understanding of

xv


xvi

Preface

NOAA

the impact of chemistry on society and on humankind’s view of itself. Topics such
as global warming, ozone depletion, acid rain, drugs, medical technology, and consumer products are covered in detail. In the early chapters, which focus primarily
on chemical and molecular concepts, many of the box features introduce these
applications and environmental concerns. The later chapters focus on these topics
directly and in more detail.

MAKING
CONNEC TIONS

538

Chapter 18

The Chemistry of Food

Chapter Summary
SOCIETAL IMPACT

MOLECULAR CONCEPT

Throughout the text, I have made
extensive efforts to help students make
connections, both between the molecular and macroscopic world and between
principles and applications. The chapter
summaries are designed to reinforce
those connections, particularly between
chemical concepts and societal impact.
The chapter summaries consist of two
columns, one summarizing the major
molecular concepts of the chapter and

the other, the impacts of those concepts
on society. By putting these summaries
side by side, the student can clearly see
the connections.

Foods are categorized as carbohydrates, proteins, and
fats/oils (18.1). The carbohydrates include sugar,
starch, and fiber and contain about four nutritional
calories per gram (except fiber, which contains none)
(18.2). The proteins supply the necessary amino acids
and contain four nutritional calories per gram;
complete proteins supply all the essential amino
acids—those the body cannot synthesize—in the right
proportion (18.3). Fats and oils are primarily triglycerides and contain nine nutritional calories per
gram. Cholesterol is a fatty substance that, along
with saturated fats, increases risk of stroke and heart
disease (18.4, 18.5).

➥

Our bodies are composed of molecules and atoms
obtained primarily from foods. The saying “you are
what you eat” is literally true—we are composed of
the foods we eat, although they are usually rearranged
and chemically modified. The kinds of foods we eat,
and therefore the proportions of carbohydrates, proteins, fats, and oils, often vary from one culture to
another. Scientists have shown, however, that certain
proportions are better than others, with the ideal being
about 45–65% carbohydrate, 10–30% protein, and less
than 20–35% fat. The average North American diet is

higher in protein and fat than the ideal diet.
Much of food goes to supplying the body’s constant
energy need, and stable weight is maintained if
caloric intake matches caloric expenditure. The North
American diet is often high in caloric content, so
many North Americans have a tendency to be overweight (18.5).

The body also needs vitamins, organic substances, in
small amounts. They can be divided into two groups:
the fat-soluble vitamins (A, D, E, and K) and the
water-soluble vitamins (C and B complex) (18.6). The
body also needs minerals, nonorganic substances, in
small amounts. These can be divided into the major
minerals (Ca, P, Mg, Na, K, Cl, and S) and the minor
minerals (Fe, Cu, Zn, I, Se, Mn, F, Cr, and Mo) (18.7).
Modern food contains many additives to preserve it
and enhance its flavor and appearance. Antimicrobial
agents are added to food to inhibit the growth of
bacteria, yeasts, and molds. Antioxidants keep food
from oxidizing when exposed to air. Artificial colors
enhance the appearance of food, and artificial flavors
enhance its taste. Stabilizers keep food’s physical
characteristics stable (18.8). Modern foods are also
grown with fertilizers to replenish nutrients in soils
and pesticides to protect crops from insects and
weeds (18.9, 18.10).

➥

➥

Vitamin and mineral supplements are popular in our
society. Many nutritionists, however, recommend that
you get the necessary vitamins and minerals from
foods. If a variety of foods are consumed, vitamin
and mineral supplements are normally not necessary;
however, deficiencies result in a number of adverse
conditions and diseases (18.6, 18.7).

Food additives must be approved by the Food and
Drug Administration. The FDA maintains that all
additives on its generally recognized as safe list can
be consumed over a lifetime with no adverse health
effects (18.8).

Chemistry on the Web
For up-to-date URLs, visit the text website at academic.cengage.com/chemistry/tro
•

The Food Pyramid
/>
A Tour of the Text
GENERAL CHAPTER STRUCTURE
Each chapter opens with a brief paragraph introducing the chapter’s main topics
and explaining to students why these topics are relevant to their lives. These
openers pose questions to help students understand the importance of the topics.
For example, the opening paragraphs to Chapter 1 state, “As you read these
pages, think about the scientific method—its inception just a few hundred years
ago has changed human civilization. What are some of those changes?
How has the scientific method directly impacted the way you and I live?”

Each chapter introduces the material
The opening paragraphs of each chapter are followed by Questions for
with Questions for Thought.
Thought directly related to chapter content. These questions are answered in
the main body of each chapter; presenting them early provides a context for
the chapter material.
Most chapters, as appropriate, follow with a description or thought experiment
about an everyday experience. The observations of the thought experiment are then
explained in molecular terms. For example, a familiar experience may be washing a
greasy dish with soapy water. Why does plain water not dissolve the grease? The
molecular reason is then given, enhanced by artwork that shows a picture of a
soapy dish and a magnification showing what happens with the molecules.
Continuing this theme, the main body of each chapter introduces chemical
principles in the context of discovering the molecular causes behind everyday
observations. What is it about helium atoms that makes it possible to breathe
small amounts of helium gas—as in a helium balloon—without adverse side


Preface

2

xvii

CHAPTER
OUTLINE

The Chemist’s
Toolbox

I

2.1

n this chapter, you will learn how to use some chemists’ tools—the

2.2
2.3

hammers, wrenches, and screwdrivers of chemistry. Just as a carpenter learns to use a hammer and a screwdriver to build a cabinet, so

2.4

you must learn to use the tools of measurement and problem solving to
build chemical knowledge. The ability to be precise and to assign num-

2.5

bers to measurements gives science much of its power. How much you
know about a physical or chemical process is often related to how well

2.6
2.7
2.8

you can measure some aspect of it. Mathematics is often called the language of modern physical science because so much of what we know
about the world can be expressed mathematically. Although this book

Curious About
Oranges

Measurement
Scientific
Measurement
Units of
Measurement
Converting Between
Units
Reading Graphs
Problem Solving
Density: A Measure
of Compactness

does not focus on the mathematical aspects of chemistry, you can’t
completely understand chemistry without at least being exposed to its
quantitative nature.

QUESTIONS FOR THOUGHT

The language of mathematics
reveals itself unreasonably
effective in the natural sciences …
a wonderful gift which we neither

●

Why is measurement
important?

●

How do we read and interpret
graphs?

●

How do we write big and
small numbers compactly?

●

How do we solve problems in
chemistry?

●

What units should we use in
reporting measurements?

●

What is density?

●

How do we convert between
different units?

understand nor deserve.

All: PhotoDisc

—Eugene Paul Wigner

effects? What is it about chlorine atoms that makes breathing chlorine gas dangerous? What happens to water molecules when water boils? These questions
have molecular answers that teach and illustrate chemical principles. The text
develops the chemical principles and concepts involved in a molecular understanding of the macroscopic observations.
Once the student is introduced to basic concepts, consumer applications and
environmental problems follow. The text, however, does not separate principles
and applications. Early chapters involving basic principles also contain applications, and later chapters with more emphasis on applications build on and
expand basic principles.

E X A M P L E S A N D YO U R T U R N
EXERCISES
Example problems are included throughout the text,
followed by related Your Turn exercises for student
practice. In designing the text, I made allowances for
different instructor preferences on quantitative material. While a course for nonmajors is not usually
highly quantitative, some instructors prefer more
quantitative material than others. To accommodate
individual preferences, many quantitative sections,
including some Examples and Your Turn exercises, can
be easily omitted. These are often placed toward the
end of chapters for easy omission. Similarly, exercises
in the back of each chapter that rely on quantitative
material can also be easily omitted. Instructors wishing
a more quantitative course should include these sections, while those wanting a more qualitative course
can skip them. The answers to the Your Turn exercises
can be found in Appendix 3.

2 electrons

Helium nucleus
2 protons
Zϭ2

8.3 Radioactivity

and are stopped with a sheet of ordinary paper. Alpha particles are the semitrucks of radioactivity—they do a lot of damage in a collision but don’t get very
far in a traffic jam.
We represent radioactive decay with a nuclear equation that shows the symbol for the initial isotope on the left and the symbols for the products of the
decay on the right. For example, U-238 decays via alpha emission to produce
Th-234 as follows:
Daughter nucleus

Parent nucleus

Alpha particle

ϩ
238
92U

234
90Th

ϩ

4
2He

The U-238 atom emits part of its nucleus, two protons and two neutrons, to form
a thorium atom. Like chemical equations, nuclear equations must be balanced; the
numbers of protons and neutrons on both sides of the equation must be equal.
This equation is balanced because the sum of the atomic numbers on the right,
90 ϩ 2, is equal to the atomic number on the left, 92. Likewise, the sum of the
mass numbers on the right, 234 ϩ 4, equals the mass number on the left, 238.
Sum of mass numbers = 238
238

U

92

234

4

Th + 2He

90

Sum of atomic numbers = 92

EXAMPLE 8.1

Writing Nuclear Equations for Alpha Decay
Write a nuclear equation to represent the alpha decay of Th-230.
SOLUTION
We write an equation showing the symbol for Th-230 (23900Th) on the left and the symbol
for an alpha particle (42He) on the right:

23 0Th
90

→ ? ϩ 42He

The isotope that thorium decays to can be determined by calculating the atomic number
and mass number that make both sides of the equation balanced. The atomic number of
the product must be 88 and the mass number must be 226. The element with atomic
number 88 is Ra; we write:
23 0Th
90

→ 22886Ra ϩ 42He

Note that the sum of atomic numbers (90) is the same on both sides of the equation and
that the sum of mass numbers (230) is the same on both sides.

YOUR TURN

Writing Nuclear Equations for Alpha Decay
Write a nuclear equation to represent the alpha decay of Ra-226.

217

Progressive Information Technologies

29


xviii

Preface

B O X E D F E AT U R E S
Molecular Thinking
Boxed features show relevance and ask
students to interact with the material.

110

Molecular Thinking boxes describe an everyday observation related to the
chapter material. The student is then asked to explain the observation
based on what the molecules are doing. For example, in Chapter 4, when
chemical equations and combustion are discussed, the Molecular Thinking
box describes how a fire will burn
hotter in the presence of wind. The
student is then asked to give a
Using Chemical Equation Coefficients as Conversion
molecular reason—based on what
Factors (Mass to Mass)
was just learned about chemical
equations and combustion—to explain this observation.

Chapter 4

Molecules, Compounds, and Chemical Reactions

YOUR TURN

One of the reactions occurring in automobile engines is the combustion of octane (C8H18):

2 C8H18 ϩ 25 O2 → 16 CO2 ϩ 18 H2O

Assume that gasoline is pure octane and that you burn approximately 6.44 x 104 grams of
octane per week (about 20 gal). How many grams of CO2 are produced?

APPLY YOUR KNOWLEDGE
Consider the following reaction: 2A ϩ 3B → 2C
If you have 2 moles of A and 6 moles of B, what is the maximum number of moles of C
that can be made by the reaction?
Answer: 2 moles of C. Even though you have enough of B to make 4 moles of C, you only have enough of
A to make 2 moles of C. The moles of A limit the amount of product that you can make.

Molecular Thinking
A campfire is a good example of a chemical reaction. As we
saw in Chapter 1, a campfire consists of molecules from
wood combining with oxygen from air to form carbon dioxide, water, and heat. Have you ever noticed that it is easier
to build a good fire if there is a breeze? It takes some extra
effort to get the fire going in the breeze, but once it ignites,
the breeze causes the fire to burn more intensely than if the
air were still. Why?
Answer: The two reactants in the campfire are the wood
and oxygen from air. In still air, the oxygen around the
wood is used up as the wood burns. In a breeze, the fire is
constantly fed more oxygen by the moving air.

Oregon Department of Forestry

Campfires

Why do fires burn more intensely in windy conditions?

4.4 Naming Compounds

TABLE 4-1
Some Common Anions
Nonmetal

Molecular Focus boxes highlight a
“celebrity” compound related to the
chapter’s material. The
physical properties and
Celebrity compounds are highlighted.
structure of the compound
are given and its use(s)
described. Featured compounds include calcium carbonate,
hydrogen peroxide, ammonia, AZT,
retinal, sulfur dioxide, ammonium
nitrate, and others.

Base Name

Anion Name

FϪ

Fluor

Fluoride

Chlorine

ClϪ

Chlor

Chloride

Bromine

BrϪ

Brom

Bromide

Iodine

IϪ

Iod

Iodide

TABLE 4-2

Oxygen

O2Ϫ

Ox

Oxide

Sulfur

S2Ϫ

Sulf

Sulfide

Some Common
Polyatomic Ions

Nitrogen

N3Ϫ

Nitr

Nitride

Name

Many ionic compounds contain anions with more than one atom. These ions
are called polyatomic ions and are tabulated in Table 4-2. In naming compounds
that contain these polyatomic ions, simply use the name of the polyatomic ion as
the name of the anion. For example, KNO3 is named according to its cation,
potassium, and its polyatomic anion, nitrate. The full name is as follows:
KNO3

Formula

Carbonate

CO32Ϫ

Bicarbonate

HCO3Ϫ

Hydroxide

OHϪ

Nitrate

NO3Ϫ

Phosphate

PO43Ϫ

Sulfate

SO42Ϫ

potassium nitrate

Molecular Focus

Calcium Carbonate
Within most chapters of this text, we will highlight a
“celebrity” compound in a Molecular Focus box. You have probably encountered these compounds in some way or another.
We begin with calcium carbonate, an ionic compound that is
abundant in nature.
Formula: CaCO3
Molar Mass: 100.09 g/mol
Melting point: 1339°C (calcite form)
Calcium carbonate is an example of an ionic compound
containing a polyatomic ion (CO32Ϫ). Calcium carbonate is
common in nature, occurring in eggshells, seashells, limestone,
and marine sediments. It occurs most dramatically in stalactites and stalagmites in limestone caves. These formations
develop over time because rainwater, containing atmospheric
CO2 that makes it acidic (more on this in Chapter 13), dissolves
calcium carbonate from soils and rocks. As the calcium
carbonate-saturated water seeps into the ground, some of the
CO2 escapes, lowering the acidity of the rainwater and causing
the calcium carbonate to deposit as a solid. When this occurs
in an underground cave, the dripping water forms structures
called stalactites, which hang down from the ceiling of a cave,
and stalagmites, which protrude up from the floor of a cave.
Calcium carbonate is used in many consumer products
because of its low toxicity, structural stability, and tendency to

Carlsbad Caverns National Park

Molecular Focus

Symbol for Ion

Fluorine

The stalactites and stalagmites of limestone caves are composed of
calcium carbonate.

neutralize acids. It is the main ingredient in a number of
building materials, including cement and marble. It also is the
main component of popular over-the-counter antacids such
as Tums and is commonly used to remove excess acidity from
wines.

97


Preface

17.14 Prozac and Zoloft: SSRIs

The Molecular Revolution

503

Molecular Revolution boxes highlight topics of modern research and
recent technology related to the
chapter’s material. Examples include
the measuring of global temperatures, imaging atoms with scanning
tunneling microscopy, and the
development of fuel cell and hybrid
electric vehicles.

Fluoxetine (Prozac), an
antidepressant.

O

F3C

CHCH2CH2NHCH3

the patient on a daily basis for a two-week period: change in appetite, change in
sleep, psychomotor agitation or retardation, loss of interest in usual activities or
decrease in sexual drive, increased fatigue, feelings of guilt or worthlessness,
slowed thinking or impaired concentration, and suicide attempt or suicidal
ideation.
Clinical depression is at least partly caused by a deficit of certain neurotransmitters in the brain, especially serotonin. It appears that serotonin deficits induce
adaptive changes in nerve cell receptors that produce the depressed state. If
serotonin levels are brought back to normal, the adaptive changes are reversed,
and the depression is relieved.
First-generation antidepressant agents, called tricyclic antidepressants, affected
the brain levels of several neurotransmitters including norepinephrine, serotonin,
and dopamine. Although they did relieve depression, they also had a number of

The Molecular Revolution
Consciousness
In this chapter, we have seen how certain molecules in the
brain can alter emotions and perceptions. Our emotions and
perceptions are susceptible to molecules because they are
mediated by molecules. In recent years, scientists have made
remarkable progress in understanding just what those molecules are and how their levels can be modified. The development of Prozac and other antidepressants is just one example
of how this understanding has benefited society.

Magnetic resonance imaging (discussed in Chapter 7) and
other technologies have been able to reveal the brain at work
by monitoring oxygen consumption and blood flow to different parts of the brain while a patient performs specific
mental tasks. For example, scientists can watch the firing of
neurons in a specific part of the brain as patients view a
particular image or as they reconstruct a particular memory.
This kind of unprecedented understanding led President Bush
(Sr.) to call the 1990s the decade of the brain. However,
President Bush may have done well to extend his definition
far into the 21st century because much remains to be
understood.
The most important question remains controversial: What is
consciousness and how does it arise? The debate on consciousness is not new; Plato and Aristotle wondered about it over
2000 years ago. Whatever consciousness is, it is central to

being human. Rene Descartes’s famous 17th-century phrase
“Cogito, ergo sum” (“I think, therefore I am”) equated consciousness with existence, and we constantly differentiate ourselves from the rest of the universe based on our concept of
self, a central part of consciousness. But scientists struggle
with explaining how the physical brain creates consciousness.
For example, a person may explain the processes associated
with seeing the color blue. Light of approximately 450 nm
strikes the retina, which causes the isomerization of a molecule called cis-retinal, which then causes an electrical signal
to be transmitted to a certain part of the brain. All of this is
known. Yet this description cannot describe what it is like to
experience the color blue. A person with perfect knowledge of
vision might be able to describe every step of the vision
process, but if that person had never seen the color blue, she
would not know what it looked like. This is the gulf that confronts neuroscience: How do electrical signals in the brain
form conscious experience? How does the physical brain create the mind? Some think this question can never be
answered. According to them, the mind will never be understood because it must rely on itself for an explanation. Others,

however, are more optimistic. They believe that with continued research and a greater understanding of the brain, the
secret of the mind will emerge.

396

Chapter 14

Oxidation and Reduction

What if . . .
The Economics of New Technologies and Corporate Handouts

What if . . . boxes discuss topics
with societal, political, or ethical
implications. At the end of the discussion there are one or more openended questions for group discussion. Topics include the Manhattan
Project, government subsidies for
the development of alternative fuels,
stem cell research, and others.

Progressive Publishing Alternatives

What if . . .

When start-up companies develop new products, they must
often survive many years of negative profitability. Investors put
money into a start-up company based on the company’s future
potential to generate profit. Companies developing new energy
technologies, such as fuel cells or batteries, for instance, often
find it difficult to attract enough investors to get through the
development stage. There are many reasons for this, such as the

immense technical difficulties that must be overcome to bring
these products to market, or the lack of infrastructure for alternate energy technologies. For example, suppose a company was
trying to develop a hydrogen fuel cell automobile. It would
never sell in the existing market because there are no roadside
stations that sell hydrogen for refueling. Consequently, the federal government often funds companies developing new energy
technologies. One publicly traded company developing fuel cell
technology has operated at a profit for several years, even
though it has no product to sell. Where does its income come
from? The federal government provides it. We, as taxpayers,
contribute to the profit of these companies.
Some believe that these types of corporate handouts are
unjustified. They think that these companies should compete

FIGURE 14-6 Zinc wire is attached
to this underground pipe at intervals
of 500–1000 ft. The zinc loses
electrons more easily than the iron
and is therefore oxidized instead of
the iron.

60

Chapter 3

Periodic Table of the Elements
7A
Hydrogen

2

2A

2
3A

4A

5A

6A

Beryllium

Boron

Carbon

Nitrogen

Oxygen

Fluorine

Neon

3

4

5

6

7

8

9

10

Li

H

Be

11

12

Na

Mg

8B
3B

4B

5B

6B

7B

Potassium Calcium Scandium Titanium Vanadium Chromium Manganese

4

19

21

20

K

Sc

Ca

Rubidium Strontium

5
6
7

8A
Helium

1
Lithium

Sodium Magnesium

3

37

38

22
Ti

23
V

24

25

Cr

Mn

1B

2B

Iron

Cobalt

Nickel

Copper

Zinc

26

27

28

29

30

Fe

Co

Ni

Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium

39
Y

40

41

42

Zr

Nb

Mo

43
Tc

44

45

46

B

C

N

Aluminum

Silicon

Phosphorus

13

14

15

Al

Si

P

Gallium Germanium Arsenic

31

32

Cu

Zn

Ga

Silver

Cadmium

Indium

Tin

47

48

49

50

Ge

33
As

O

F

Sulfur

Chlorine

16

17

Ne

Ar
Krypton

35

36

Se

52

Br

Kr

Iodine

Xenon

53

54

Rb

Sr

Ru

Rh

Pd

Ag

Cd

In

Sn

Sb

Te

I

Xe

Barium

Osmium

Iridium

Platinum

Gold

Mercury

Thallium

Lead

Bismuth

Polonium

Astatine

Radon

56

57

72

73

74

75

76

77

78

79

80

81

82

83

84

85

86

Cs

Ba

La

Hf

Ta

W

Re

Os

Ir

Pt

Au

Hg

Tl

Pb

Bi

Po

At

Rn

Francium

Radium

87

88

89

104

Fr

Ra

Ac

Rf

Lanthanum Hafnium Tantalum Tungsten Rhenium

Actinium Rutherfordium Dubnium

Seaborgium

Bhorium

Hassium

Meitnerium

105

106

107

108

109

Db

Sg

Bh

Hs

Mt

Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium

Fr

Name
Atomic
number (Z)
Symbol

Explore this topic on the
Interactive Periodic Table
website.

58

59

60

61

62

63

Ce

Pr

Nd

Pm

Sm

Eu

Thorium Protactinium Uranium Neptunium Plutonium Americium

64
Gd
Curium

Erbium

65

66

67

68

Tb

Dy

Ho

Er

Thulium Ytterbium Lutetium

69
Tm

70
Yb

A P P LY YO U R
KNOWLEDGE

18

Cl
Bromine

34

55

87

Since one-fifth of the iron produced in the United States goes to replace
rusted iron, the prevention of rust is a robust industry. Although no rust prevention system is completely effective, the rusting of iron can be temporarily halted
or slowed. The simplest way to prevent rust is to cover iron with paint. The paint
excludes water and acts as a barrier between air and the iron; because the redox
reaction requires airborne oxygen and water, the metal is protected. The paint
will only work, however, as long as it remains intact. Any break or nick in the
paint will expose the iron and lead to rust.
Another way to protect iron from rusting, often used in underground pipes,
is to attach a more active metal to it (Figure 14-6). The more active metal has a
higher tendency to give up electrons than iron does. Zinc and magnesium are
common choices because they are stable in air yet have a strong tendency to lose
electrons. The active metal protects the iron because it oxidizes in place of the
iron. Eventually, much of the active metal oxidizes and needs replacing. However,
as long as the active metal remains, the iron is protected.
The rusting of iron can also be prevented by mixing or coating the iron
with another metal whose oxide is structurally stable. Many metals—such as
aluminum, for example—will oxidize in air much as iron does but form structurally
stable oxides. The corrosion resistance of aluminum cans testifies to the structural
stability of aluminum oxide (Al2O3). The aluminum oxide forms a tough film that

protects the underlying metal from further oxidation. For iron, zinc is often used as
a coating in a process called galvanization. Because zinc is more active than iron,
it will oxidize instead of the underlying iron. The zinc oxide then forms a protective coat, preventing further oxidation. One advantage of this technique is that the
zinc coating prevents oxidation of the underlying iron even if the coating becomes

Argon

S
Selenium

Antimony Tellurium

51

He

Cesium

Francium

QUESTION: What do you think? What if the federal government actually billed oil companies for maintaining stability in
the Middle East or for acid rain damage? How would that influence oil company profitability? Should the government sustain
the profits of new energy technology companies? What if these
companies never generate a profit independently, but simply
survive on government subsidies?

Atoms and Elements

1A
1

on the open market just like everyone else. If their product is
good enough, they argue, it will sell and generate profit. Others, however, believe the hurdles to developing alternate
energy sources are so high and the benefits of their development so great that additional help is justified. The government, they argue, currently subsidizes fossil-fuel technology
by absorbing much of the costs associated with the environmental damage of fossil fuels or by fighting wars that guard
oil interests. In their view, the government’s indirect subsidies
to fossil fuels far outweigh subsidies given to new technology
companies.

71
Lu

Berkelium Californium Einsteinium Fermium Mendelevium Noblelium Lawrencium

90

91

92

93

94

95

96

97

98

99

100

101

102

103

Th

Pa

U

Np

Pu

Am

Cm

Bk

Cf

Es

Fm

Md

No

Lr

FIGURE 3-4 The periodic table lists all known elements in order of increasing atomic number. Some elements
from the bottom rows of the table are shown separately to make the table more compact.

APPLY YOUR KNOWLEDGE
Your friend tells you about an article that he read in a tabloid that reported the discovery
of a new form of carbon containing eight protons in the nucleus of its atoms. According
to the article, this form of carbon spontaneously turns into diamond. How would you
respond to your friend?
Answer: You should tell your friend that the “form of carbon containing eight protons” was discovered long
ago, and it is not carbon at all. We call it oxygen and it does not form diamonds.

on the inside front cover of this book and an alphabetical listing of the elements
on the inside back cover.

3.3 Electrons
A neutral atom has as many electrons outside of its nucleus as protons inside of its
nucleus. Therefore, a hydrogen atom has one electron, a helium atom has two
electrons, and a carbon atom has six electrons. Electrons have a very small mass
compared to protons (0.00055 amu) and are negatively charged. Electrons therefore
experience a strong attraction to the positively charged nucleus. This attraction

In the Apply Your Knowledge boxes, the
student is asked to use a conceptual idea
to answer a practical question. For
instance, in Chapter 3, the Apply Your
Knowledge box presents the situation of
a friend who tells you that a tabloid
reported the discovery of a new form of
carbon that contains eight protons in the
nucleus of its atoms and spontaneously
turns into diamond. How would you
respond to your friend? These quick

xix


xx

Preface

Key Terms

49

Chapter Summary
MOLECULAR CONCEPT

SOCIETAL IMPACT

Scientists must be curious people who naturally ask

the question why (2.1). They must then make observations on some aspect of nature, devise laws from
those observations, and finally create a theory to
give insight into reality. The tools needed for this
procedure revolve around measurement (2.2).
When making measurements, we must be consistent
in our use of units. Numbers should always be written with their corresponding units, and units guide
our way through calculations. The standard SI unit of
length is the meter (m); of mass, the kilogram (kg);
and of time, the second (s) (2.4).

Scientists often present their measurements in graphs,
which reveal trends in data but which must be interpreted correctly (2.6). Many problems in chemistry
can be thought of as conversions from one set of
units to another (2.5). Density is the mass-to-volume
ratio of an object and provides a conversion factor
between mass and volume (2.8).

➥

➥

➥

The ability to measure quantities in nature gives science much of its power. Without this ability, we
would probably not have cars, computers, or cable
TV today. Neither science nor technology could
advance very far without measurement (2.2).

The decision over which units to use is societal.
Americans have consistently differed from the rest of

the world in using English units over metric units.
We are slowly changing, however, and with time, we
should be consistent with other nations. For scientific
measurements, always use metric units (2.4).

When reading newspapers or magazines, be careful
to pay attention to units and to the axes shown in
graphs. Clever writers can distort statistical or graphical data, amplifying the changes they want you to
see and diminishing the ones they want to hide (2.6).

concept checks are designed to reinforce the key concepts in the text,
develop students’ critical-thinking
skills, and help them relate the material to the world around them.

CHAPTER
SUMMARIES

Chapters end with a two-column
summary of the ideas presented in
the main body of the chapter. In this
Chapter summaries review main
summary, students get a side-bymolecular concepts and their societal
side review of the chapter with
impacts.
molecular concepts in one column
Key Terms
and the coinciding societal impact
in the other. The chapter summary
allows the student to get an overall
picture of the chapter and strengthens the connection between principles and

applications.
Chemistry on the Web

For up-to-date URLs, visit the text website at academic.cengage.com/chemistry/tro
•

Richard Feynman
/>
•

Global Warming
/> />
•

SI Units
/>
conversion factor

kilogram (kg)

meter (m)

unit

density

mass

second (s)

volume

CHEMISTRY ON THE WEB
The Chemistry on the Web section features a list of URLs for the websites referenced within the chapter. They can easily be assigned for further exploration or
research. Weblinks are also provided on the Student Book Companion Web Site,
which is accessible from academic.cengage.com/chemistry/tro.

KEY TERMS
Each chapter has a set of key terms from within that chapter for review and
study. Each of the key terms is defined in the Glossary at the end of the text.

STUDENT EXERCISES
All chapters contain exercises of four types: questions, problems, points to ponder,
and feature problems and projects. The questions ask the student to recall many of
the key concepts from the chapter. The problems ask the student to apply what they
have learned to solve problems similar to those in the chapter Examples and Your
Turn boxes. The points to ponder consist primarily of open-ended short-essay questions in which students are asked about the ethical, societal, and political implications of scientific issues. The feature problems and projects contain problems with
graphics and short projects, often involving web-based inquiry.

NE W TO THIS EDITION
The fourth edition of Chemistry in Focus contains several changes from the previous edition.

• Interest boxes have been updated or revised to reflect progress and current
issues.


Preface

• The sections on the Scientific Method have been expanded and properly integrated into other sections of the book.

• All real-world information in figures and tables has been updated to the latest possible data.

• Chapter openers redesigned to include a chapter outline.
• Each sentence has been analyzed and when needed rewritten for greater
clarity.

• More than 10% of the problems are new or modified from the previous
edition.

• All artwork has been analyzed and when needed modified or redrawn for
greater clarity and aesthetics.
Below is a list of some of the specific changes in the book.

• Chapter 10 contains substantial text revisions and includes a new “What
If. . .” box entitled “Legislating Renewable Energy.”

• Chapter 16 contains substantial text revisions and the latest real-world data.
•
•

The chapter also includes a new “The Molecular Revolution” box entitled
“The Human Genome Project.”
Chapter 17 contains substantial text revisions and the latest real-world data.
Chapter 19 has been completely rewritten and also contains the latest realworld data.

Accompanying Materials
Online Instructor’s Resource Manual
Written by Ann Tro of Westmont College and updated by Richard Jarman of the
College of DuPage, this manual contains detailed solutions to all of the end-ofchapter problems in the text. The Instructor’s Manual is on the Faculty Book Companion Web Site, which is accessible from academic.cengage.com/chemistry/tro.

ExamView (Windows/Macintosh)
With this easy-to-use software, professors can create, deliver, and customize tests
in minutes. The test bank includes problems and questions representing every
chapter in the text. Answers are provided on a separate grading key, making it
easy to use the questions for tests, quizzes, or homework assignments. ExamView
is packaged as a hybrid CD for both Windows and Macintosh users. ISBN
0495605492

Test Bank on eBank
The Test Bank, revised by Stephen J. Glueckert of the University of Southern
Indiana, features more than 700 multiple-choice questions for instructors to use
for tests, quizzes, or homework assignments. Your Brooks/Cole representative can
give you access to the Test Bank files in Word and PDF format.

Microsoft® PowerPoint® Slides
A presentation tool created by Jeannine Eddleton of Virginia Polytechnic Institute
and State University, these slides provide text, art, photos, and tables in an electronic format that is easily exported into other software packages. In addition,
you can customize your presentations by importing your own personal lecture
slides or notes. The slides can be found on the Faculty Book Companion Web
Site, which is accessible from academic.cengage.com/chemistry/tro.

xxi


xxii

Preface

Student Book Companion Web Site
Organized by chapter, this outstanding site features chapter-by-chapter online

quizzes and weblinks from the Chemistry on the Web sections in the textbook.

OWL: Online Web-based Learning System
Developed at the University of Massachusetts, Amherst, and class-tested by thousands of students, OWL is a fully customizable and flexible web-based homework
system and assessment tool with course management. With both numerical and
chemical parameterization and useful, specific feedback built right in, OWL produces several thousand questions correlated to this text. The OWL system also
features a database of simulations, guided tutorials, and problems correlated to
the textbook content. Instructors are able to customize the OWL program, use the
grade book feature, and generate multiple reports. OWL provides an excellent
solution for those who wish to place more emphasis on the quantitative aspects
of chemistry.

Inquiry-based Laboratories for Liberal Arts Chemistry
By Vickie Williamson and Larry Peck of Texas A&M University, Inquiry-based
Laboratories for Liberal Arts Chemistry offers 19 experiments. The focus of the
manual is conceptual learning of the chemical phenomena in our everyday lives.
It employs the learning cycle approach, which is used as the underlying model
for the guided and open inquiry/application laboratories. An online instructor’s
guide is also available on Williamson and Peck’s Faculty Book Companion Web
Site, which is accessible from academic.cengage.com/chemistry/williamson.

Everyday Chemistry Labs for Introductory Chemistry
By Dr. Charles E. Carraher, Jr. of Florida Atlantic University, these experiments
are designed to be relatively easy and fun and enhance student’s understanding
of the fundamental chemical concepts that are covered in class. Most of the
materials are usually available in student’s homes or can be easily obtained.

Acknowledgments
I am grateful to my colleagues at Westmont College, who have given me the
space to write this book. I am especially grateful to Warren Rogers, Allan

Nishimura, David Marten, Mako Masuno, and Steven Contakes for their support.
Thanks to Don Neu for his great help with the nanotechnology chapter. I am
grateful to my editors, Lisa Lockwood and Jay Campbell, who have been incredibly gracious and helpful to me throughout this revision. I am also grateful to
Cathy Leonard, from Lachina Publishing Services, who was attentive to every
detail and was a wonderful person to work with. Lisa Weber handled the media
that accompanies the text.
Thanks also to those who supported me personally while writing this book. I
am particularly grateful to my wife, Ann, whose love healed a broken man.
Thanks to my children, Michael, Ali, Kyle, and Kaden—they are my raison d’ etre.
I come from a large and close extended Cuban family who has stuck by me
through all manner of difficult circumstances. I thank my parents, Nivaldo and
Sara, and my siblings, Sarita, Mary, and Jorge. Thanks also to Pam—may her
spirit rest in peace.
I am greatly indebted to the reviewers of each of the editions of this book
who are listed below. They have all left marks on the work you are now holding.
Lastly, I thank my students, whose lives energize me and whose eyes continually


Preface

xxiii

provide a new way for me to see the world. I am particularly grateful to my student Dustin Jones and former student Jon Rea who helped me in the preparation
and proofreading of the manuscript for the fourth edition.
—Nivaldo J. Tro
Westmont College

FOURTH EDITION REVIEWERS
Holly Bevsek, The Citadel
Michael J. Dorko, The Citadel

Jeannine Eddleton, Virginia Polytechnic Institute and
State University
Konstantinos Kavallieratos, Florida International
University

Swadeshmukul Santra, University of Central Florida
James Schreck, University of Northern Colorado
Joseph W. Shane, Shippensburg University
Christopher L Truitt, Texas Tech University

THIRD EDITION REVIEWERS
Jeannine Eddleton, Virginia Polytechnic Institute and
State University
Stephen J. Glueckert, University of Southern Indiana
Michael Hampton, University of Central Florida
Karen Hanner, Washington State Community College
Eileen Hinks, Virginia Military Institute

Richard H. Jarman, College of DuPage
Gregory A. Oswald, North Dakota State University
Vicki Berger Paulissen, Eastern Michigan University
Albert Plaush, Saginaw Valley State University
Anne Marie Sokol, Buffalo State College
Nhu-Y Stessman, California State University, Stanislaus

SECOND EDITION RE VIE WERS
Thomas Goyne, Valparaiso University
Katrina Hartman, Aquinas College

William C. McHarris, Michigan State University

Anne Marie Sokol, Buffalo State College

FIRST EDITION REVIEWERS
Ronald Backus, American River College
Morris Bader, Moravian College
Ronald Baumgarten, University of Illinois at Chicago
Barbara Burke, California State Polytechnic
University, Pomona
Marvin Dixon, William Jewell College
Jeff Draves, University of Central Arkansas
Jerry Driscoll, University of Utah
Lawrence Duffy, University of Alaska, Fairbanks
Karen Eichstadt, Ohio University
Seth Elsheimer, University of Central Florida
Gordon Ewing, New Mexico State University
Sharon L. Garlund, Pima Community College
Patrick Garvey, Des Moines Area Community College
James Golen, University of Massachusetts, Dartmouth
Marie Herrmann, University of Cincinnati—Raymond
Walters College
Toney Keeney, Southwest Texas Junior College
Keith Kennedy, St. Cloud State University
Leslie N. Kinsland, University of Southwestern Louisiana
David Lippmann, Southwest Texas State University
Kenneth Loach, State University of New York College
at Plattsburgh

Lawrence Mack, Bloomsburg University
Joyce Miller, University of Wisconsin, Platteville
Joseph P. Nunes, State University of New York College

of Agriculture and Technology at Cobleskill
Gordon Parker, University of Michigan, Dearborn
Alan Pribula, Towson University
Edith Rand, East Carolina University
Martin Salzman, Providence College
Elsa Santos, Colorado State University
George Schenk, Wayne State University
James Schreck, University of Northern Colorado
Kerri Scott, University of Mississippi
Dennis L. Steven, University of Nevada, Las Vegas
Dan M. Sullivan, University of Nebraska at Omaha
Tamar Susskind, Oakland Community College
Joseph Tausta, State University of New York College
at Oneonta
Naola VanOrden, Sacramento City College
George Wahl, North Carolina State University
Robert Wallace, Bentley College
Karen Weaver, University of Central Arkansas
Sidney Young, University of Southern Alabama


1

Molecular Reasons

Lake: © Royalty-Free/CORBIS; ripples: Charles
D. Winters

Science, like art, is fun, a playing
with truths. . . .

—W. H. Auden