化学原理 了解原子和分子的世界 英文版 原书第3版【2025|PDF|Epub|mobi|kindle电子书版本百度云盘下载】

化学原理 了解原子和分子的世界 英文版 原书第3版PDF格式电子书版下载

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1 Chemistry Is a Molecular Science1

Looking at the World of Atoms and Molecules1

1.1 CHEMISTRY IS INTEGRAL TO OUR LIVES2

1.2 SCIENCE IS A WAY OF UNDERSTANDING THE UNIVERSE5

A Study of Sea Butterflies Illustrates the Process of Science6

Reproducibility and an Attitude of Inquiry Are Essential Components of Science8

A Theory Is a Single Idea That Has Great Explanatory Power9

Science Has Limitations9

Science Can Lead to Profound New Ideas10

Science Helps Us Learn the Rules of Nature11

1.3 SCIENTISTS MEASURE PHYSICAL QUANTITIES12

CALCULATION CORNER UNIT CONVERSION12

1.4 MASS IS HOW MUCH AND VOLUME IS HOW SPACIOUS14

HANDS-ON CHEMISTRY PENNY FINGERS15

HANDS-ON CHEMISTRY DECISIVE DIMENSIONS16

1.5 ENERGY IS THE MOVER OF MATTER18

1.6 TEMPERATURE IS A MEASURE OF HOW HOT—HEAT IT IS NOT19

1.7 THE PHASE OF A MATERIAL DEPENDS ON THE MOTION OF ITS PARTICLES22

Familiar Terms Are Used to Describe Changing Phases23

HANDS-ON CHEMISTRY HOT-WATER BALLOON24

1.8 DENSITY IS THE RATIO OF MASS TO VOLUME25

CALCULATION CORNER MANIPULATING AN ALGEBRAIC EQUATION27

IN PERSPECTIVE27

A Word about Chapter Endmatter from the Author28

IN THE SPOTLIGHT PSEUDOSCIENCE36

2 Elements of Chemistry39

Understanding Chemistry through Its Language39

2.1 MATTER HAS PHYSICAL AND CHEMICAL PROPERTIES40

HANDS-ON CHEMISTRY FIRE WATER44

Determining Whether a Change Is Physical Or Chemical Can Be Difficult45

2.2 ATOMS ARE THE FUNDAMENTAL COMPONENTS OF ELEMENTS47

2.3 ELEMENTS CAN COMBINE TO FORM COMPOUNDS49

Compounds Are Named According to the Elements They Contain50

HANDS-ON CHEMISTRY OXYGEN BUBBLE BURSTS51

2.4 MOST MATERIALS ARE MIXTURES52

Mixtures Can Be Separated by Physical Means53

HANDS-ON CHEMISTRY BOTTOMS UP AND BUBBLES OUT55

2.5 CHEMISTS CLASSIFY MATTER AS PURE OR IMPURE55

CALCULATION CORNER HOW PURE IS PURE?57

2.6 ELEMENTS ARE ORGANIZED IN THE PERIODIC TABLE BY THEIR PROPERTIES59

A Period Is a Horizontal Row,a Group a Vertical Column61

IN PERSPECTIVE64

IN THE SPOTLIGHT EXTENDING THE HUMAN LIFE SPAN72

3 Discovering the Atom and Subatomic Particles75

Where We've Been and What We Now Know75

3.1 CHEMISTRY DEVELOPED OUT OF OUR INTEREST IN MATERIALS76

3.2 LAVOISIER LAID THE FOUNDATION OF MODERN CHEMISTRY77

Mass Is Conserved in a Chemical Reaction77

HANDS-ON CHEMISTRY AIR OUT79

Proust Proposed the Law of Definite Proportions80

HANDS-ON CHEMISTRY COLLECTING BUBBLES81

3.3 DALTON DEDUCED THAT MATTER IS MADE OF ATOMS81

CALCULATION CORNER FINDING OUT HOW MUCH OF A CHEMICAL REACTS82

Dalton Defended His Atomic Hypothesis Against Experimental Evidence83

Mendeleev Used Known Relative Atomic Masses to Create the Periodic Table85

3.4 THE ELECTRON WAS THE FIRST SUBATOMIC PARTICLE DISCOVERED87

HANDS-ON CHEMISTRY BENDING ELECTRONS90

3.5 THE MASS OF AN ATOM IS CONCENTRATED IN ITS NUCLEUS90

3.6 THE ATOMIC NUCLEUS IS MADE OF PROTONS AND NEUTRONS92

CALCULATION CORNER CALCULATING ATOMIC MASS95

IN PERSPECTIVE96

IN THE SPOTLIGHT NANOTECHNOLOGY104

4 The Atomic Nucleus107

Know Nukes4.1 THE CATHODE RAY LED TO THE DISCOVERY OF RADIOACTIVITY108

The Three Major Products of Radioactivity Are Alpha,Beta,and Gamma Rays110

4.2 RADIOACTIVITY IS A NATURAL PHENOMENON112

Rems Are Units of Radiation112

HANDS-ON CHEMISTRY PERSONAL RADIATION114

4.3 RADIOACTIVE ISOTOPES ARE USEFUL AS TRACERS AND FOR MEDICAL IMAGING115

4.4 RADIOACTIVITY RESULTS FROM AN IMBALANCE OF FORCES IN THE NUCLEUS116

4.5 A RADIOACTIVE ELEMENT CAN TRANSMUTE TO A DIFFERENT ELEMENT119

4.6 THE SHORTER THE HALF-LIFE,THE GREATER THE RADIOACTIVITY120

HANDS-ON CHEMISTRY RADIOACTIVE PAPER CLIPS122

4.7 ISOTOPIC DATING MEASURES THE AGE OF A MATERIAL123

4.8 NUCLEAR FISSION IS THE SPLITTING OF THE ATOMIC NUCLEUS125

Nuclear Fission Reactors Convert Nuclear Energy to Electrical Energy128

The Breeder Reactor Breeds Its Own Fuel129

4.9 NUCLEAR ENERGY COMES FROM NUCLEAR MASS AND VICE VERSA130

4.10 NUCLEAR FUSION IS THE COMBINING OF ATOMIC NUCLEI132

The Holy Grail of Nuclear Research Today Is Controlled Fusion133

IN PERSPECTIVE134

IN THE SPOTLIGHT MERCURY EMISSIONS140

5 Atomic Models143

Virtual Handles on the Very Real5.1 MODELS HELP US VISUALIZE THE INVISIBLE WORLD OF ATOMS144

5.2 LIGHT IS A FORM OF ENERGY147

5.3 ATOMS CAN BE IDENTIFIED BY THE LIGHT THEY EMIT150

HANDS-ON CHEMISTRY SPECTRAL PATTERNS151

5.4 NIELS BOHR USED THE QUANTUM HYPOTHESIS TO EXPLAIN ATOMIC SPECTRA151

5.5 ELECTRONS EXHIBITWAVE PROPERTIES155

HANDS-ON CHEMISTRY RUBBER WAVES157

Probability Clouds and Atomic Orbitals Help Us Visualize Electron Waves157

HANDS-ON CHEMISTRY QUANTIZED WHISTLE160

5.6 ENERGY-LEVEL DIAGRAMS DESCRIBE HOW ORBITALS ARE OCCUPIED161

5.7 ORBITALS OF SIMILAR ENERGIES CAN BE GROUPED INTO SHELLS165

5.8 THE PERIODIC TABLE HELPS US PREDICT PROPERTIES OF ELEMENTS168

The Smallest Atoms Are at the Upper Right of the Periodic Table170

The Smallest Atoms Have the Most Strongly Held Electrons172

IN PERSPECTIVE174

IN THE SPOTLIGHT QUARKS AND LEPTONS182

6 Chemical Bonding and Molecular Shapes185

How Atoms Connect to One Another185

6.1 AN ATOMIC MODEL IS NEEDED TO UNDERSTAND HOW ATOMS BOND186

6.2 ATOMS CAN LOSE OR GAIN ELECTRONS TO BECOME IONS187

Molecules Can Form Ions190

6.3 IONIC BONDS RESULT FROM A TRANSFER OF ELECTRONS191

HANDS-ON CHEMISTRY UP CLOSE WITH CRYSTALS193

6.4 COVALENT BONDS RESULT FROM A SHARING OF ELECTRONS194

6.5 VALENCE ELECTRONS DETERMINE MOLECULAR SHAPE198

Molecular Shape Is Defined by Where the Substituent Atoms Are201

HANDS-ON CHEMISTRY GUMDROP MOLECULES203

6.6 POLAR COVALENT BONDS RESULT FROM AN UNEVEN SHARING OF ELECTRONS203

6.7 MOLECULAR POLARITY RESULTS FROM AN UNEVEN DISTRIBUTION OF ELECTRONS206

IN PERSPECTIVE211

IN THE SPOTLIGHT WATER FLUORIDATION218

7 Molecular Mixing221

How Molecules Attract One Another221

7.1 SUBMICROSCOPIC PARTICLES ELECTRICALLY ATTRACT ONE ANOTHER222

Ions and Polar Molecules Attract One Another222

Polar Molecules Attract Other Polar Molecules223

Polar Molecules Can Induce Dipoles in Nonpolar Molecules224

Atoms and Nonpolar Molecules Can Form Temporary Dipoles on Their Own225

HANDS-ON CHEMISTRY CIRCULAR RAINBOWS228

7.2 A SOLUTION IS A SINGLE-PHASE HOMOGENEOUS MIXTURE228

CALCULATION CORNER CALCULATING FOR SOLUTIONS232

HANDS-ON CHEMISTRY OVERFLOWING SWEETNESS233

7.3 SOLUBILITY IS A MEASURE OF HOW WELL A SOLUTE DISSOLVES233

Solubility Changes with Temperature236

Gases Are More Soluble at Low Temperatures and High Pressures236

HANDS-ON CHEMISTRY CRYSTAL CRAZY238

Nonpolar Gases Readily Dissolve in Perfluorocarbons239

7.4 SOAP WORKS BY BEING BOTH POLAR AND NONPOLAR240

Detergents Are Synthetic Soaps242

Hard Water Makes Soap Less Effective242

IN PERSPECTIVE244

IN THE SPOTLIGHT PARTIALLY HYDROGENATED FATS252

8 Those Incredible Water Molecules255

Macroscopic Consequences of Molecular Stickiness255

8.1 WATER MOLECULES FORM AN OPEN CRYSTALLINE STRUCTURE IN ICE256

HANDS-ON CHEMISTRY A SLICE OF ICE258

8.2 FREEZING AND MELTING GO ON AT THE SAME TIME259

Water Is Densest at 4℃261

8.3 THE BEHAVIOR OF LIQUID WATER IS THE RESULT OF THE STICKINESS OF WATER MOLECULES263

The Surface of Liquid Water Behaves Like an Elastic Film264

Capillary Action Results from the Interplay of Adhesive and Cohesive Forces266

8.4 WATER MOLECULES MOVE FREELY BETWEEN THE LIQUID AND GASEOUS PHASES267

Boiling is Evaporation Beneath a Liquid Surface271

8.5 IT TAKES A LOT OF ENERGY TO CHANGE THE TEMPERATURE OF LIQUID WATER274

CALCULATION CORNER HOW HEAT CHANGES TEMPERATURE276

Global Climates Are Influenced by Water's High Specific Heat276

HANDS-ON CHEMISTRY RACING TEMPERATURES278

8.6 A PHASE CHANGE REQUIRES THE INPUT OR OUTPUT OF ENERGY278

IN PERSPECTIVE281

IN THE SPOTLIGHT GLOBAL WARMING AND THE KYOTO PROTOCOL288

9 An Overview of Chemical Reactions291

How Reactants React to Form Products291

9.1 CHEMICAL REACTIONS ARE REPRESENTED BY CHEMICAL EQUATIONS292

9.2 CHEMISTS USE RELATIVE MASSES TO COUNT ATOMS AND MOLECULES294

The Periodic Table Helps Us Convert Between Grams and Moles297

CALCULATION CORNER FIGURING MASSES OF REACTANTS AND PRODUCTS299

9.3 REACTION RATE IS INFLUENCED BY CONCENTRATION AND TEMPERATURE299

9.4 CATALYSTS INCREASE THE RATE OF CHEMICAL REACTIONS305

9.5 CHEMICAL REACTIONS CAN BE EITHER EXOTHERMIC OR ENDOTHERMIC307

An Exothermic Reaction Involves a Net Release of Energy309

An Endothermic Reaction Involves a Net Absorption of Energy310

HANDS-ON CHEMISTRY WARMING AND COOLING WATER MIXTURES312

9.6 ENTROPY IS A MEASURE OF DISPERSED ENERGY312

Substances Contain Dispersed Energy313

Heats of Reaction Affect Entropy315

The Laws of Thermodynamics317

IN PERSPECTIVE318

IN THE SPOTLIGHT DOUBLING TIME326

10 Acids and Bases329

Transferring Protons329

10.1 ACIDS DONATE AND BASES ACCEPT POSITIVE CHARGE330

The Br？nsted-Lowry Definition Focuses on Protons331

The Lewis Definition Focuses on Lone Pairs334

A Salt Is the Ionic Product of an Acid-Base Reaction335

10.2 SOME ACIDS AND BASES ARE STRONGER THAN OTHERS337

10.3 SOLUTIONS CAN BE ACIDIC,BASIC,OR NEUTRAL340

The pH Scale Is Used to Describe Acidity343

CALCULATION CORNER LOGARITHMS AND pH344

HANDS-ON CHEMISTRY RAINBOW CABBAGE345

10.4 RAINWATER IS ACIDIC AND OCEAN WATER IS BASIC345

10.5 BUFFER SOLUTIONS RESIST CHANGES IN pH350

IN PERSPECTIVE353

IN THE SPOTLIGHT HAIR AND SKIN CARE360

11 Oxidation and Reduction363

Transferring Electrons363

11.1 OXIDATION IS THE LOSS OF ELECTRONS AND REDUCTION IS THE GAIN OF ELECTRONS364

11.2 PHOTOGRAPHY WORKS BY SELECTIVE OXIDATION AND REDUCTION366

HANDS-ON CHEMISTRY SILVER LINING368

11.3 THE ENERGY OF FLOWING ELECTRONS CAN BE HARNESSED368

The Electricity of a Battery Comes from Oxidation-Reduction Reactions370

Fuel Cells Are Highly Efficient Sources of Electrical Energy374

Electrical Energy Can Produce Chemical Change377

11.4 OXYGEN IS RESPONSIBLE FOR CORROSION AND COMBUSTION378

HANDS-ON CHEMISTRY SPLITTING WATER378

IN PERSPECTIVE382

IN THE SPOTLIGHT THE WONDER CHEMICAL,BUT...388

12 Organic Compounds391

A Survey of Carbon-Based Molecules391

12.1 HYDROCARBONS CONTAIN ONLY CARBON AND HYDROGEN392

12.2 UNSATURATED HYDROCARBoNS CONTAIN MULTIPLE BONDS396

HANDS-ON CHEMISTRY TWISTING JELLY BEANS398

12.3 ORGANIC MOLECULES ARE CLASSIFIED BY FUNCTIONAL GROUP400

Alcohols Contain the Hydroxyl Group401

Phenols Contain an Acidic Hydroxyl Group402

The Oxygen of an Ether Group Is Bonded to Two Carbon Atoms404

Amines Form Alkaline Solutions405

Ketones,Aldehydes,Amides,Carboxylic Acids,and Esters All Contain a Carbonyl Group407

12.4 ORGANIC MOLECULES CAN LINK TO FORM POLYMERS411

Addition Polymers Result from the Joining Together of Monomers413

Condensation Polymers Form with the Loss of Small Molecules416

HANDS-ON CHEMISTRY RACING WATER DROPS418

IN PERSPECTIVE419

IN THE SPOTLIGHT THE GENETICS OF MUSCLE FITNESS428

13 Chemicals of Life431

The Nutrients That Make Up Our Bodies431

13.1 BIOMOLECULES ARE PRODUCED AND UTILIZED IN CELLS432

13.2 CARBOHYDRATES GIVE STRUCTURE AND ENERGY433

Polysaccharides Are Complex Carbohydrates434

HANDS-ON CHEMISTRY SPIT IN BLUE437

13.3 LIPIDS ARE INSOLUBLE IN WATER440

Fats Are Used for Energy and Insulation440

Steroids Contain Four Carbon Rings441

13.4 PROTEINS ARE POLYMERS OF AMINO ACIDS444

Protein Structure Is Determined by Attractions Between Neighboring Amino Acids444

Enzymes Are Biological Catalysts451

13.5 NUCLEIC ACIDS CODE FOR PROTEINS451

DNA Is the Template of Life452

One Gene Codes for One Polypeptide455

RNA Is Largely Responsible for Protein Synthesis455

Genetic Engineering458

13.6 VITAMINS ARE ORGANIC,MINERALS ARE INORGANIC462

13.7 METABOLISM IS THE CYCLING OF BIOMOLECULES THROUGH THE BODY465

13.8 THE FOOD PYRAMID SUMMARIZES A HEALTHFUL DIET466

Carbohydrates Predominate in Most Foods467

Unsaturated Fats Are Generally More Healthful Than Saturated Fats470

Our Intake of Essential Amino Acids Should Be Carefully Monitored471

HANDS-ON CHEMISTRY SIZZLE SOURCES471

IN PERSPECTIVE473

14 The Chemistry of Drugs479

Understanding Drug Action479

14.1 DRUGS ARE CLASSIFIED BY SAFETY,SOCIAL ACCEPTABI LITY,ORIGIN,AND BIOLOGICAL ACTIVITY480

14.2 THE LOCK-AND-KEY MODEL GUIDES CHEMISTS IN SYNTHESIZING NEW DRUGS482

14.3 CHEMOTHERAPY CURES THE HOST BY KILLING THE DISEASE485

Sulfa Drugs and Antibiotics Treat Bacterial Infections485

Chemotherapy Can Inhibit the Ability of Viruses to Replicate487

Cancer Chemotherapy Attacks Rapidly Growing Cells489

14.4 SOME DRUGS EITHER BLOCK OR MIMIC PREGNANCY492

14.5 THE NERVOUS SYSTEM IS A NETWORK OF NEURONS493

HANDS-ON CHEMISTRY DIFFUSING NEURONS495

Neurotransmitters Include Norepinephrine,Acetylcholine,Dopamine,Serotonin,and GABA495

14.6 PSYCHOACTIVE DRUGS ALTER THE MIND OR BEHAVIOR497

Stimulants Activate the Stress Neurons497

Hallucinogens and Cannabinoids Alter Perceptions501

Depressants Inhibit the Ability of Neurons to Conduct Impulses504

14.7 PAIN RELIEVERS INHIBIT THE TRANSMISSION OR PERCEPTION OF PAIN507

14.8 DRUGS FOR THE HEART OPEN BLOOD VESSELS OR ALTER HEART RATE511

IN PERSPECTIVE513

15 Optimizing Food Production519

From the Good Earth519

15.1 HUMANS EAT AT ALL TROPHIC LEVELS520

15.2 PLANTS REQUIRE NUTRIENTS522

Plants Utilize Nitrogen,Phosphorus,and Potassium522

Plants Also Utilize Calcium,Magnesium,and Sulfur525

15.3 SOIL FERTILITY IS DETERMINED BY SOIL STRUCTURE AND NUTRIENT RETENTION526

Soil Readily Retains Positively Charged Ions527

HANDS-ON CHEMISTRY YOUR SOIL'S pH—A QUALITATIVE MEASURE530

15.4 NATURAL AND SYNTHETIC FERTILIZERS HELP RESTORE SOIL FERTILITY530

15.5 PESTICIDES KILL INSECTS,WEEDS,AND FUNGI532

Insecticides Kill Insects533

HANDS-ON CHEMISTRY CLEANING YOUR INSECTS536

Herbicides Kill Weeds536

Fungicides Kill Fungi538

15.6 THERE IS MUCH TO LEARN FROM PAST AGRICULTURAL PRACTICES538

15.7 HIGH AGRICULTURAL YIELDS CAN BE SUSTAINED WITH PROPER PRACTICES541

Organic Farming Is Environmentally Friendly542

Integrated Crop Management Is a Strategy for Sustainable Agriculture542

15.8 A CROP CAN BE IMPROVED BY INSERTING A GENE FROM ANOTHER SPECIES544

IN PERSPECTIVE546

16 Fresh Water Resources553

Our Roles and Responsibilities553

16.1 WATER CIRCULATES THROUGH THE HYDROLOGIC CYCLE554

16.2 COLLECTIVELY,WE CONSUME HUGE AMOUNTS OF WATER556

HANDS-ON CHEMISTRY WATER WISER558

16.3 WATER TREATMENT FACILITIES MAKE WATER SAFE FOR DRINKING559

16.4 FRESH WATER CAN BE MADE FROM SALT WATER561

HANDS-ON CHEMISTRY MICRO WATER PURIFIER565

16.5 HUMAN ACTIVITIES CAN POLLUTE WATER565

16.6 MICROORGANISMS IN WATER ALTER LEVELS OF DISSOLVED OXYGEN568

16.7 WASTEWATER IS PROCESSED BY TREATMENT FACILITIES569

Advanced Integrated Pond Systems Treat Wastewater571

IN PERSPECTIVE572

17 Air Resources579

One Planet,One Atmosphere579

17.1 EARTH'S ATMOSPHERE IS A MIXTURE OF GASES580

CALCULATION CORNER DENSE AS AIR582

HANDS-ON CHEMISTRY ATMOSPHERIC CAN-CRUSHER583

17.2 GAS LAWS DESCRIBE THE BEHAVIOR OF GASES583

Boyle's Law:Pressure and Volume583

Charles's Law:Volume and Temperature584

Avogadro's Law:Volume and Number of Particles585

The Ideal Gas Law586

CALCULATION CORNER HOT AIR BALLOONS588

17.3 HUMAN ACTIVITIES HAVE INCREASED AIR POLLUTION588

Aerosols and Particulates Facilitate Chemical Reactions Involving Pollutants589

There Are Two Kinds of Smog590

Catalytic Converters Reduce Automobile Emissions593

17.4 STRATOSPHERIC OZONE PROTECTS EARTH FROM ULTRAVIOLET RADIATION594

17.5 AIR POLLUTION MAY RESULT IN GLOBAL WARMING597

Atmospheric Carbon Dioxide Is a Greenhouse Gas598

The Potential Effects of Global Warming Are Uncertain600

IN PERSPECTIVE602

18 Material Resources609

A Look at the Materials of Our Society609

18.1 PAPER IS MADE OF CELLULOSE FIBERS610

HANDS-ON CHEMISTRY PAPERMAKING611

18.2 THE DEVELOPMENT OF PLASTICS INVOLVED EXPERIMENTATION AND DISCOVERY612

Collodion and Celluloid Begin with Nitrocellulose614

Bakelite Was the First Widely Used Plastic614

The First Plastic Wrap Was Cellophane615

Polymers Win in World War Ⅱ616

Attitudes about Plastics Have Changed618

18.3 METALS COME FROM THE EARTH'S LIMITED SUPPLY OF ORES619

We Should Conserve and Recycle Metals621

18.4 METAL-CONTAINING COMPOUNDS CAN BE CONVERTED TO METALS622

Some Metals Are Most Commonly Obtained from Metal Oxides623

Other Metals Are Most Commonly Obtained from Metal Sulfides626

18.5 GLASS IS MADE PRIMARILY OF SILICATES626

18.6 CERAMICS ARE HARDENED WITH HEAT628

Ceramic Superconductors Have No Electrical Resistance629

18.7 COMPOSITES COMBINE FIBERS AND A THERMOSET MEDIUM630

HANDS-ON CHEMISTRY A COMPOSITE OF WHITE GLUE AND THREAD631

IN PERSPECTIVE632

19 Energy Resources637

Managing for the Present and the Future637

19.1 ELECTRICITY IS A CONVENIENT FORM OF ENERGY638

What's a Watt?639

CALCULATION CORNER KILOWATT-HOURS639

19.2 FOSSIL FUELS ARE A WIDELY USED BUT LIMITED ENERGY SOURCE640

Coal Is the Filthiest Fossil Fuel643

Petroleum Is the King of Fossil Fuels644

Natural Gas Is the Purest Fossil Fuel645

19.3 THERE ARE TWO FORMS OF NUCLEAR ENERGY646

Nuclear Fission Generates Some of Our Electricity647

Nuclear Fusion Is a Potential Source of Clean Energy650

19.4 WHAT ARE SUSTAINABLE ENERGY SOURCES?651

19.5 WATER CAN BE USED TO GENERATE ELECTRICITY652

Hydroelectric Power Comes from the Kinetic Energy of Flowing Water652

Temperature Differences in the Ocean Can Generate Electricity653

Geothermal Energy Comes from Earth's Interior654

The Energy of Ocean Tides Can Be Harnessed656

19.6 BIOMASS IS CHEMICAL ENERGY656

Fuels Can Be Obtained from Biomass657

Biomass Can Be Burned to Generate Electricity658

19.7 ENERGY CAN BE HARNESSED FROM SUNLIGHT658

Solar Heat Is Easily Collected658

Solar Thermal Electric Generation Produces Electricity659

HANDS-ON CHEMISTRY SOLAR POOL COVER660

Wind Power Is Cheap and Widely Available660

Photovoltaics Convert Sunlight Directly to Electricity662

19.8 OUR FUTURE ECONOMY MAY BE BASED ON HYDROGEN665

Fuel Cells Produce Electricity from Fuel666

Photovoltaic Cells Can Be Used to Produce Hydrogen from Water666

But Hydrogen May Not Be the Ultimate Solution667

IN PERSPECTIVE667