Raymond Chang - Chemistry, Tenth Edition PDF

 10 th EDITION CHEMISTRY Raymond Chang Williams College CHEMISTRY, TENTH EDITION Published by McGraw-Hill, a business unit of The McGraw-Hill Companies, Inc., 1221 Avenue of the Americas, New York, NY 10020. Copyright © 2010 by The McGraw-Hill Companies, Inc. All rights reserve...

 10 th EDITION CHEMISTRY Raymond Chang Williams College CHEMISTRY, TENTH EDITION Published by McGraw-Hill, a business unit of The McGraw-Hill Companies, Inc., 1221 Avenue of the Americas, New York, NY 10020. Copyright © 2010 by The McGraw-Hill Companies, Inc. All rights reserved. Previous editions © 2007, 2005, and 2002. No part of this publication may be reproduced or distributed in any form or by any means, or stored in a database or retrieval system, without the prior written consent of The McGraw-Hill Companies, Inc., including, but not limited to, in any network or other electronic storage or transmission, or broadcast for distance learning. Some ancillaries, including electronic and print components, may not be available to customers outside the United States. This book is printed on acid-free paper. 1 2 3 4 5 6 7 8 9 0 DOW/DOW 0 9 ISBN 978–0–07–351109–2 MHID 0–07–351109–9 Publisher: Thomas D. Timp Senior Sponsoring Editor: Tamara L. Hodge Director of Development: Kristine Tibbetts Senior Developmental Editor: Shirley R. Oberbroeckling Marketing Manager: Todd L. Turner Senior Project Manager: Gloria G. Schiesl Senior Production Supervisor: Kara Kudronowicz Lead Media Project Manager: Judi David Senior Designer: David W. Hash Cover/Interior Designer: Jamie E. O’Neal (USE) Cover Image: water ripple, ©Biwa Inc./Getty Images Senior Photo Research Coordinator: John C. Leland Photo Research: Toni Michaels/PhotoFind, LLC Supplement Producer: Mary Jane Lampe Compositor: Aptara®, Inc. Typeface: 10/12 Times Roman Printer: R. R. Donnelley Willard, OH The credits section for this book begins on page C-1 and is considered an extension of the copyright page. Library of Congress Cataloging-in-Publication Data Chang, Raymond. Chemistry. — 10th ed. / Raymond Chang. p. cm. Includes index. ISBN 978–0–07–351109–2 — ISBN 0–07–351109–9 (hard copy : acid-free paper) 1. Chemistry— Textbooks. I. Title. QD31.3.C38 2010 540—dc22 2008033016 www.mhhe.com  ABOUT THE AUTHOR Raymond Chang was born in Hong Kong and grew up in Shanghai and Hong Kong. He received his B.Sc. degree in chemistry from London University, England, and his Ph.D. in chemistry from Yale University. After doing postdoctoral research at Washington University and teaching for a year at Hunter College of the City University of New York, he joined the chemistry department at Williams College, where he has taught since 1968. Professor Chang has served on the American Chemical Society Examination Committee, the National Chemistry Olympiad Examination Committee, and the Graduate Record Examinations (GRE) Committee. He is an editor of The Chemical Educator. Professor Chang has written books on physical chemistry, industrial chemistry, and physical science. He has also coauthored books on the Chinese language, children’s pic- ture books, and a novel for young readers. For relaxation, Professor Chang maintains a forest garden; plays ten- nis, Ping-Pong, and the harmonica; and practices the violin. iii iv Contents 1 Chemistry: The Study of Change 2 2 Atoms, Molecules, and Ions 40 3 Mass Relationships in Chemical Reactions 78 4 Reactions in Aqueous Solutions 120 5 Gases 172 6 Thermochemistry 228 7 Quantum Theory and the Electronic Structure of Atoms 274 8 Periodic Relationships Among the Elements 322 9 Chemical Bonding I: Basic Concepts 364 10 Chemical Bonding II: Molecular Geometry and Hybridization of Atomic Orbitals 408 11 Intermolecular Forces and Liquids and Solids 460 12 Physical Properties of Solutions 512 13 Chemical Kinetics 556 14 Chemical Equilibrium 614 15 Acids and Bases 658 16 Acid-Base Equilibria and Solubility Equilibria 712 17 Chemistry in the Atmosphere 768 18 Entropy, Free Energy, and Equilibrium 800 19 Electrochemistry 836 20 Metallurgy and the Chemistry of Metals 884 21 Nonmetallic Elements and Their Compounds 912 22 Transition Metals Chemistry and Coordination Compounds 952 23 Nuclear Chemistry 986 24 Organic Chemistry 1024 25 Synthetic and Natural Organic Polymers 1060 APPENDIX 1 Derivation of the Names of Elements A-1 APPENDIX 2 Units for the Gas Constant A-7 APPENDIX 3 Thermodynamic Data at 1 atm and 25°C A-8 APPENDIX 4 Mathematical Operations A-13 iv List of Applications xviii List of Animations xx Preface xxi Tools for Success xxviii A Note to the Student xxxii Chemistry: The Study of Change 2 1.1 Chemistry: A Science for the Twenty-First Century 4 1.2 The Study of Chemistry 7 1.3 The Scientific Method 8 CHEMISTRY in Action Primordial Helium and the Big Bang Theory 10 1.4 Classifications of Matter 10 1.5 The Three States of Matter 13 1.6 Physical and Chemical Properties of Matter 14 1.7 Measurement 16 CHEMISTRY in Action The Importance of Units 21 1.8 Handling Numbers 22 1.9 Dimensional Analysis in Solving Problems 27 Key Equations 31 Summary of Facts and Concepts 31 Key Words 31 Questions and Problems 32 CHEMICAL Mystery The Disappearance of the Dinosaurs 38 Atoms, Molecules, and Ions 40 2.1 The Atomic Theory 42 2.2 The Structure of the Atom 43 2.3 Atomic Number, Mass Number, and Isotopes 49 2.4 The Periodic Table 51 CHEMISTRY in Action Distribution of Elements on Earth and in Living Systems 52 2.5 Molecules and Ions 53 2.6 Chemical Formulas 55 2.7 Naming Compounds 59 v vi Contents 2.8 Introduction to Organic Compounds 68 Key Equation 70 Summary of Facts and Concepts 70 Key Words 70 Questions and Problems 71 Mass Relationships in Chemical Reactions 78 3.1 Atomic Mass 80 3.2 Avogadro’s Number and Molar Mass of an Element 81 3.3 Molecular Mass 85 3.4 The Mass Spectrometer 88 3.5 Percent Composition of Compounds 88 3.6 Experimental Determination of Empirical Formulas 92 3.7 Chemical Reactions and Chemical Equations 94 3.8 Amounts of Reactants and Products 99 3.9 Limiting Reagents 103 3.10 Reaction Yield 106 CHEMISTRY in Action Chemical Fertilizers 108 Key Equations 109 Summary of Facts and Concepts 109 Key Words 109 Questions and Problems 110 Reactions in Aqueous Solutions 120 4.1 General Properties of Aqueous Solutions 122 4.2 Precipitation Reactions 124 CHEMISTRY in Action An Undesirable Precipitation Reaction 129 4.3 Acid-Base Reactions 129 4.4 Oxidation-Reduction Reactions 135 CHEMISTRY in Action Breathalyzer 146 4.5 Concentration of Solutions 147 4.6 Gravimetric Analysis 151 4.7 Acid-Base Titrations 153 4.8 Redox Titrations 156 CHEMISTRY in Action Metal from the Sea 158 Key Equations 159 Summary of Facts and Concepts 159  Contents vii Key Words 160 Questions and Problems 160 CHEMICAL Mystery Who Killed Napoleon? 170 Gases 172 5.1 Substances That Exist as Gases 174 5.2 Pressure of a Gas 175 5.3 The Gas Laws 179 5.4 The Ideal Gas Equation 185 5.5 Gas Stoichiometry 194 5.6 Dalton’s Law of Partial Pressures 196 CHEMISTRY in Action Scuba Diving and the Gas Laws 202 5.7 The Kinetic Molecular Theory of Gases 201 CHEMISTRY in Action Super Cold Atoms 210 5.8 Deviation from Ideal Behavior 211 Key Equations 214 Summary of Facts and Concepts 214 Key Words 215 Questions and Problems 215 CHEMICAL Mystery Out of Oxygen 226 Thermochemistry 228 6.1 The Nature of Energy and Types of Energy 230 6.2 Energy Changes in Chemical Reactions 231 6.3 Introduction to Thermodynamics 233 CHEMISTRY in Action Making Snow and Inflating a Bicycle Tire 239 6.4 Enthalpy of Chemical Reactions 239 6.5 Calorimetry 245 CHEMISTRY in Action Fuel Values of Foods and Other Substances 251 6.6 Standard Enthalpy of Formation and Reaction 252 CHEMISTRY in Action How a Bombardier Beetle Defends Itself 257 6.7 Heat of Solution and Dilution 258 Key Equations 261 Summary of Facts and Concepts 261 viii Contents Key Words 262 Questions and Problems 262 CHEMICAL Mystery The Exploding Tire 272 Quantum Theory and the Electronic Structure of Atoms 274 7.1 From Classical Physics to Quantum Theory 276 7.2 The Photoelectric Effect 280 7.3 Bohr’s Theory of the Hydrogen Atom 282 CHEMISTRY in Action Laser—The Splendid Light 288 7.4 The Dual Nature of the Electron 288 CHEMISTRY in Action Electron Microscopy 292 7.5 Quantum Mechanics 293 7.6 Quantum Numbers 294 7.7 Atomic Orbitals 297 7.8 Electron Configuration 300 7.9 The Building-Up Principle 307 Key Equations 311 Summary of Facts and Concepts 311 Key Words 312 Questions and Problems 312 CHEMICAL Mystery Discovery of Helium and the Rise and Fall of Coronium 320 Periodic Relationships Among the Elements 322 8.1 Development of the Periodic Table 324 8.2 Periodic Classification of the Elements 326 8.3 Periodic Variation in Physical Properties 330 CHEMISTRY in Action The Third Liquid Element? 337 8.4 Ionization Energy 337 8.5 Electron Affinity 341 8.6 Variation in Chemical Properties of the Representative Elements 344 CHEMISTRY in Action Discovery of the Noble Gases 355  Contents ix Key Equation 356 Summary of Facts and Concepts 356 Key Words 356 Questions and Problems 356 Chemical Bonding I: Basic Concepts 364 9.1 Lewis Dot Symbols 366 9.2 The Ionic Bond 367 9.3 Lattice Energy of Ionic Compounds 369 CHEMISTRY in Action Sodium Chloride—A Common and Important Ionic Compound 373 9.4 The Covalent Bond 374 9.5 Electronegativity 377 9.6 Writing Lewis Structures 380 9.7 Formal Charge and Lewis Structure 383 9.8 The Concept of Resonance 386 9.9 Exceptions to the Octet Rule 389 CHEMISTRY in Action Just Say NO 393 9.10 Bond Enthalpy 394 Key Equation 399 Summary of Facts and Concepts 399 Key Words 399 Questions and Problems 400 Chemical Bonding II: Molecular Geometry and Hybridization of Atomic Orbitals 408 10.1 Molecular Geometry 410 10.2 Dipole Moment 420 CHEMISTRY in Action Microwave Ovens—Dipole Moments at Work 424 10.3 Valance Bond Theory 424 10.4 Hybridization of Atomic Orbitals 428 10.5 Hybridization in Molecules Containing Double and Triple Bonds 437 10.6 Molecular Orbital Theory 440 10.7 Molecular Orbital Configurations 443 10.8 Delocalized Molecular Orbitals 448 CHEMISTRY in Action Buckyball, Anyone? 450 Key Equations 452 Summary of Facts and Concepts 452 Key Words 453 Questions and Problems 453 x Contents Intermolecular Forces and Liquids and Solids 460 11.1 The Kinetic Molecular Theory of Liquids and Solids 462 11.2 Intermolecular Forces 463 11.3 Properties of Liquids 469 CHEMISTRY in Action Why Do Lakes Freeze from the Top Down? 473 11.4 Crystal Structure 472 11.5 X-Ray Diffraction by Crystals 480 11.6 Types of Crystals 482 CHEMISTRY in Action High-Temperature Superconductors 486 11.7 Amorphous Solids 486 CHEMISTRY in Action And All for Want of a Button 488 11.8 Phase Changes 489 11.9 Phase Diagrams 498 CHEMISTRY in Action Hard-Boiling an Egg on a Mountaintop, Pressure Cookers, and Ice Skating 500 CHEMISTRY in Action Liquid Crystals 501 Key Equations 503 Summary of Facts and Concepts 503 Key Words 504 Questions and Problems 504 Physical Properties of Solutions 512 12.1 Types of Solutions 514 12.2 A Molecular View of the Solution Process 515 12.3 Concentration Units 517 12.4 The Effect of Temperature on Solubility 521 12.5 The Effect of Pressure on the Solubility of Gases 524 CHEMISTRY in Action The Killer Lake 526 12.6 Colligative Properties of Nonelectrolyte Solutions 526 12.7 Colligative Properties of Electrolyte Solutions 539 CHEMISTRY in Action Desalination 541  Contents xi 12.8 Colloids 541 Key Equations 545 Summary of Facts and Concepts 545 Key Words 545 Questions and Problems 546 CHEMICAL Mystery The Wrong Knife 554 Chemical Kinetics 556 13.1 The Rate of a Reaction 558 13.2 The Rate Law 565 13.3 The Relation Between Reactant Concentration and Time 569 CHEMISTRY in Action Determining the Age of the Shroud of Turin 580 13.4 Activation Energy and Temperature Dependence of Rate Constants 582 13.5 Reaction Mechanisms 588 CHEMISTRY in Action Femtochemistry 593 13.6 Catalysis 594 Key Equations 601 Summary of Facts and Concepts 602 Key Words 602 Questions and Problems 602 Chemical Equilibrium 614 14.1 The Concept of Equilibrium and the Equilibrium Constant 616 14.2 Writing Equilibrium Constant Expressions 618 14.3 The Relationship Between Chemical Kinetics and Chemical Equilibrium 630 14.4 What Does the Equilibrium Constant Tell Us? 632 14.5 Factors That Affect Chemical Equilibrium 638 CHEMISTRY in Action Life at High Altitudes and Hemoglobin Production 645 CHEMISTRY in Action The Haber Process 646 Key Equations 646 Summary of Facts and Concepts 646 Key Words 647 Questions and Problems 648 xii Contents Acids and Bases 658 15.1 Brønsted Acids and Bases 660 15.2 The Acid-Base Properties of Water 661 15.3 pH—A Measure of Acidity 663 15.4 Strength of Acids and Bases 666 15.5 Weak Acids and Acid Ionization Constants 670 15.6 Weak Bases and Base Ionization Constants 678 15.7 The Relationship Between the Ionization Constants of Acids and Their Conjugate Bases 680 15.8 Diprotic and Polyprotic Acids 681 15.9 Molecular Structure and the Strength of Acids 685 15.10 Acid-Base Properties of Salts 689 15.11 Acid-Base Properties of Oxides and Hydroxides 695 15.12 Lewis Acids and Bases 697 CHEMISTRY in Action Antacids and the pH Balance in Your Stomach 698 Key Equations 701 Summary of Facts and Concepts 701 Key Words 702 Questions and Problems 702 CHEMICAL Mystery Decaying Papers 710 Acid-Base Equilibria and Solubility Equilibria 712 16.1 Homogeneous versus Heterogeneous Solution Equilibria 714 16.2 The Common Ion Effect 714 16.3 Buffer Solutions 717 CHEMISTRY in Action Maintaining the pH of Blood 724 16.4 Acid-Base Titrations 723 16.5 Acid-Base Indicators 732 16.6 Solubility Equilibria 735 16.7 Separation of Ions by Fractional Precipitation 742 16.8 The Common Ion Effect and Solubility 744 16.9 pH and Solubility 746 16.10 Complex Ion Equilibria and Solubility 749 CHEMISTRY in Action How an Eggshell Is Formed 753  Contents xiii 16.11 Application of the Solubility Product Principle to Qualitative Analysis 754 Key Equation 756 Summary of Facts and Concepts 757 Key Words 757 Questions and Problems 757 CHEMICAL Mystery A Hard-Boiled Snack 766 Chemistry in the Atmosphere 768 17.1 Earth’s Atmosphere 770 17.2 Phenomena in the Outer Layers of the Atmosphere 773 17.3 Depletion of Ozone in the Stratosphere 775 17.4 Volcanoes 780 17.5 The Greenhouse Effect 781 17.6 Acid Rain 785 17.7 Photochemical Smog 789 17.8 Indoor Pollution 791 Summary of Facts and Concepts 794 Key Words 794 Questions and Problems 794 Entropy, Free Energy, and Equilibrium 800 18.1 The Three Laws of Thermodynamics 802 18.2 Spontaneous Processes 802 18.3 Entropy 803 18.4 The Second Law of Thermodynamics 808 CHEMISTRY in Action The Efficiency of Heat Engines 814 18.5 Gibbs Free Energy 814 18.6 Free Energy and Chemical Equilibrium 821 CHEMISTRY in Action The Thermodynamics of a Rubber Band 826 18.7 Thermodynamics in Living Systems 825 Key Equations 828 Summary of Facts and Concepts 828 Key Words 828 Questions and Problems 829 xiv Contents Electrochemistry 836 19.1 Redox Reactions 838 19.2 Galvanic Cells 841 19.3 Standard Reduction Potentials 843 19.4 Thermodynamics of Redox Reactions 849 19.5 The Effect of Concentration of Cell Emf 852 19.6 Batteries 857 CHEMISTRY in Action Bacteria Power 861 19.7 Corrosion 862 19.8 Electrolysis 866 CHEMISTRY in Action Dental Filling Discomfort 871 Key Equations 872 Summary of Facts and Concepts 873 Key Words 873 Questions and Problems 873 CHEMICAL Mystery Tainted Water 882 Metallurgy and the Chemistry of Metals 884 20.1 Occurrence of Metals 886 20.2 Metallurgical Processes 886 20.3 Band Theory of Electrical Conductivity 894 20.4 Periodic Trends in Metallic Properties 896 20.5 The Alkali Metals 897 20.6 The Alkaline Earth Metals 901 20.7 Aluminum 903 CHEMISTRY in Action Recycling Aluminum 906 Summary of Facts and Concepts 906 Key Words 907 Questions and Problems 908  Contents xv Nonmetallic Elements and Their Compounds 912 21.1 General Properties of Nonmetals 914 21.2 Hydrogen 914 CHEMISTRY in Action Metallic Hydrogen 919 21.3 Carbon 920 CHEMISTRY in Action Synthetic Gas from Coal 923 21.4 Nitrogen and Phosphorus 924 CHEMISTRY in Action Ammonium Nitrate—The Explosive Fertilizer 931 21.5 Oxygen and Sulfur 932 21.6 The Halogens 939 Summary of Facts and Concepts 946 Key Words 946 Questions and Problems 947 Transition Metals Chemistry and Coordination Compounds 952 22.1 Properties of the Transition Metals 954 22.2 Chemistry of Iron and Copper 957 22.3 Coordination Compounds 959 22.4 Structure of Coordination Compounds 964 22.5 Bonding in Coordination Compounds: Crystal Field Theory 967 22.6 Reactions of Coordination Compounds 973 22.7 Applications of Coordination Compounds 974 CHEMISTRY in Action Coordination Compounds in Living Systems 976 CHEMISTRY in Action Cisplatin—The Anticancer Drug 978 Key Equation 976 Summary of Facts and Concepts 976 Key Words 978 Questions and Problems 979 CHEMICAL Mystery Dating Paintings with Prussian Blue 984 xvi Contents Nuclear Chemistry 986 23.1 The Nature of Nuclear Reactions 988 23.2 Nuclear Stability 990 23.3 Natural Radioactivity 995 23.4 Nuclear Transmutation 999 23.5 Nuclear Fission 1001 CHEMISTRY in Action Nature’s Own Fission Reactor 1006 23.6 Nuclear Fusion 1007 23.7 Uses of Isotopes 1010 23.8 Biological Effects of Radiation 1012 CHEMISTRY in Action Food Irradiation 1014 CHEMISTRY in Action Boron Neutron Capture Therapy 1015 Key Equations 1015 Summary of Facts and Concepts 1016 Key Words 1016 Questions and Problems 1016 CHEMICAL Mystery The Art Forgery of the Twentieth Century 1022 Organic Chemistry 1024 24.1 Classes of Organic Compounds 1026 24.2 Aliphatic Hydrocarbons 1026 CHEMISTRY in Action Ice That Burns 1038 24.3 Aromatic Hydrocarbons 1039 24.4 Chemistry of the Functional Groups 1042 CHEMISTRY in Action The Petroleum Industry 1048 Summary of Facts and Concepts 1051 Key Words 1051 Questions and Problems 1052 CHEMICAL Mystery The Disappearing Fingerprints 1058  Contents xvii Synthetic and Natural Organic Polymers 1069 25.1 Properties of Polymers 1062 25.2 Synthetic Organic Polymers 1062 25.3 Proteins 1067 CHEMISTRY in Action Sickle Cell Anemia—A Molecular Disease 1074 25.4 Nucleic Acids 1076 CHEMISTRY in Action DNA Fingerprinting 1079 Summary of Facts and Concepts 1080 Key Words 1080 Questions and Problems 1081 CHEMICAL Mystery A Story That Will Curl Your Hair 1084 APPENDIX 1 Derivation of the Names of Elements A-1 APPENDIX 2 Units for the Gas Constant A-7 APPENDIX 3 Thermodynamic Data at 1 atm and 25°C A-8 APPENDIX 4 Mathematical Operations A-13 Glossary G-1 Answers to Even-Numbered Problems AP-1 Credits C-1 Index I-1  The opening sentence of this text is, “Chemistry is an active, evolving science that has vital importance to our world, in both the realm of nature and the realm of soci- ety.” Throughout the text, Chemistry in Action and Chemical Mysteries give specific examples of chemistry as active and evolving in all facets of our lives. CHEMISTRY in Action Primordial Helium and the Big Bang Theory 10 The Importance of Units 21 Distribution of Elements on Earth and in Living Systems 52 Chemical Fertilizers 108 An Undesirable Precipitation Reaction 129 Breathalyzer 146 Metal from the Sea 158 Scuba Diving and the Gas Laws 202 Super Cold Atoms 210 Making Snow and Inflating a Bicycle Tire 239 Fuel Values of Foods and Other Substances 251 How a Bombardier Beetle Defends Itself 257 Laser—The Splendid Light 288 Electron Microscopy 292 The Third Liquid Element? 337 Discovery of the Noble Gases 355 Sodium Chloride—A Common and Important Ionic Compound 373 Just Say NO 393 Microwave Ovens—Dipole Moments at Work 424 Buckyball, Anyone? 450 Why Do Lakes Freeze from the Top Down? 473 High-Temperature Superconductors 486 And All for the Want of a Button 488 Hard-Boiling an Egg on a Mountaintop, Pressure Cookers, and Ice Skating 500 Liquid Crystals 501 The Killer Lake 526 Desalination 541 Determining the Age of the Shroud of Turin 580 Femtochemistry 593 Life at High Altitudes and Hemoglobin Production 645 The Haber Process 646 Antacids and the pH Balance in Your Stomach 698 xviii  List of Applications xix Maintaining the pH of Blood 724 How an Eggshell Is Formed 753 The Efficiency of Heat Engines 814 The Thermodynamics of a Rubber Band 826 Bacteria Power 861 Dental Filling Discomfort 871 Recycling Aluminum 906 Metallic Hydrogen 919 Synthetic Gas from Coal 923 Ammonium Nitrate—The Explosive Fertilizer 931 Coordination Compounds in Living Systems 976 Cisplatin—The Anticancer Drug 978 Nature’s Own Fission Reactor 1006 Food Irradiation 1014 Boron Neutron Capture Therapy 1015 Ice That Burns 1038 The Petroleum Industry 1048 Sickle Cell Anemia—A Molecular Disease 1075 DNA Fingerprinting 1079 CHEMICAL Mysteries The Disappearance of the Dinosaurs 38 Who Killed Napoleon? 170 Out of Oxygen 226 The Exploding Tire 272 Discovery of Helium and the Rise and Fall of Coronium 320 The Wrong Knife 554 Decaying Papers 710 A Hard-Boiled Snack 766 Tainted Water 882 Dating Paintings with Prussian Blue 984 The Art Forgery of the Twentieth Century 1021 The Disappearing Fingerprints 1058 A Story That Will Curl Your Hair 1084  The animations below are correlated to Chemistry Emission spectra (7.3) within each chapter in two ways. The first is the Equilibrium vapor pressure (11.8) Student Interactive Activity found in the open- Galvanic cells (19.2) ing pages of every chapter. Then within the chapter are The gas laws (5.3) icons letting the student and instructor know that an ani- Heat flow (6.2) mation is available for a specific topic. Animations can be Hybridization (10.4) found online in the Chang ARIS website. Hydration (4.1) Ionic vs. covalent bonding (9.4) Chang Animations (Chapter/Section) Le Châtelier’s principle (14.5) Limiting reagent (3.9) Absorption of color (22.5) Making a solution (4.5) Acid-base titrations (16.4) Millikan oil drop (2.2) Acid ionization (15.5) Nuclear fission (23.5) Activation energy (13.4) Neutralization reactions (4.3) Alpha, beta, and gamma rays (2.2) Orientation of collisions (13.4) Alpha-particle scattering (2.2) Osmosis (12.6) Aluminum production (20.7) Oxidation-reduction reactions (4.4) Atomic and ionic radius (8.3) Packing spheres (11.4) Base ionization (15.6) Polarity of molecules (10.2) Buffer solutions (16.3) Precipitation reactions (4.2) Catalysis (13.6) Preparing a solution by dilution (4.5) Cathode ray tube (2.2) Radioactive decay (23.3) Chemical equilibrium (14.1) Resonance (9.8) Chirality (22.4 & 24.2) Sigma and pi bonds (10.5) Collecting a gas over water (5.6) Strong electrolytes, weak electrolytes, and Diffusion of gases (5.7) nonelectrolytes (4.1) Dissolution of an ionic and a covalent compound (12.2) VSEPR (10.1) Electron configurations (7.8) xx F rom the first edition, my aim has been to write a Many sections have been revised and updated based general chemistry text that provides a firm foun- on the comments from reviewers and users. Some dation in chemical concepts and principles and to examples include: instill in students an appreciation of the vital part chem- — Revised the treatment of Amounts of Reactants istry plays in our daily life. It is the responsibility of the and Products in Chapter 3. textbook author to assist both instructors and their stu- — Revised the explanation of thermochemical equa- dents in their pursuit of this objective by presenting a tions in Chapter 6. broad range of topics in a logical manner. I have tried — Expanded coverage on effective nuclear charge in to strike a balance between theory and application and Chapter 8. to illustrate basic principles with everyday examples — Revised the treatment of orientation factor in whenever possible. Chapter 13. In this tenth edition, as in previous editions, my goal — Revised the discussion of entropy in Chapter 18. is to create a text that is clear in explaining abstract con- — Added a new Chemistry in Action (Boron Neutron cepts, concise so that it does not overburden students with Capture Therapy) in Chapter 23. unnecessary extraneous information, yet comprehensive enough so that it prepares students to move on to the next level of learning. The encouraging feedback I have re- Problem Solving ceived from instructors and students has convinced me The development of problem-solving skills has always that this approach is effective. been a major objective of this text. The two major catego- ries of learning are the worked examples and end of chap- What’s New in This Edition? ter problems. Many of them present extra tidbits of knowledge and enable the student to solve a chemical NEW to the chapters is Review of Concepts. This is problem that a chemist would solve. The examples and a quick knowledge test for the student to gauge his or problems show students the real world of chemistry and her understanding of the concept just presented. The applications to everyday life situations. answers to the Review of Concepts are available in Worked examples follow a proven step-by-step the Student Solutions Manual and on the companion strategy and solution. ARIS (Assessment, Review, and Instruction System) website. — Problem statement is the reporting of the facts needed to solve the problem based on the question NEW are powerful connections to electronic home- posed. work. All of the practice exercises for the Worked — Strategy is a carefully thought-out plan or method Examples in all chapters are now found within the to serve as an important function of learning. ARIS (Assessment, Review, and Instruction System) — Solution is the process of solving a problem given electronic homework system. Each end-of-chapter in a stepwise manner. problem in ARIS is noted in the Electronic Home- — Check enables the student to compare and verify work Problem section. with the source information to make sure the an- Many NEW end-of-chapter problems with graphical swer is reasonable. representation of molecules have been added to test — Practice Exercise provides the opportunity to solve the conceptual comprehension and critical thinking a similar problem in order to become proficient in skills of the student. The more challenging problems this problem type. The Practice Exercises are avail- are listed under the Special Problems section. able in the ARIS electronic homework system. The NEW computer-generated molecular orbital diagrams marginal note lists additional similar problems to are presented in Chapter 10. work in the end-of-chapter problem section. xxi xxii Preface End-of-Chapter problems are organized in various Marginal Notes are used to provide hints and feed- ways. Each section under a topic heading begins back to enhance the knowledge base for the student. with Review Questions followed by Problems. Worked Examples along with the accompanying The Additional Problems section provides more Practice Exercise is a very important tool for learn- problems not organized by sections. Finally, the ing and mastering chemistry. The problem-solving Special Problems section contains more challeng- steps guide the student through the critical thinking ing problems. necessary for succeeding in chemistry. Using sketches helps student understand the inner workings of a problem. (See Example 6.1 on page 237.) A margin Visualization note lists similar problems in the end-of-chapter Graphs and Flow Charts are important in science. problems section, enabling the student to apply new In Chemistry, flow charts show the thought process skill to other problems of the same type. Answers to of a concept and graphs present data to comprehend the Practice Exercises are listed at the end of the the concept. chapter problems. Molecular art appears in various formats to serve Review of Concepts enables the student to evaluate different needs. Molecular models help to visualize whether they understand the concept presented in the the three-dimensional arrangement of atoms in a mol- section. Answers to the Review of Concepts can be ecule. Electrostatic potential maps illustrate the elec- found in the Student Solution Manual and online in tron density distribution in molecules. Finally, there the accompanying ARIS companion website. is the macroscopic-to-microscopic art, helping stu- Key Equations are highlighted within the chapter, dents understand processes at the molecular level. drawing the student’s eye to material that needs to be Photos are used to help students become familiar understood and retained. The key equations are also with chemicals and understand how chemical reac- presented in the chapter summary materials for easy tions appear in reality. access in review and study. Figures of apparatus enable the student to visualize Summary of Facts and Concepts provides a quick the practical arrangement in a chemistry laboratory. review of concepts presented and discussed in detail within the chapter. Key Words are a list of all important terms to help Study Aids the student understand the language of chemistry. Setting the Stage On the two-page opening spread for each chapter the chapter outline, Student Interactive Activity, and A Look Testing Your Knowledge Ahead appear. Review of Concepts lets the student pause and test his/her understanding of the concept presented and Chapter Outline enables the student to see at a discussed in the section. Answers to the Review of glance the big picture and focus on the main ideas of Concepts can be found in the Student Solution Man- the chapter. ual and online in the accompanying ARIS compan- Student Interactive Activity shows where the elec- ion website. tronic media are used in the chapter. A list of the End-of-Chapter Problems enable the student to animations, media player material, and questions in practice critical thinking and problem-solving skills. ARIS homework, as well as the questions with ac- The problems are broken into various types: cess to an electronic tutorial is given. Within the chapter, icons are used to refer to the items shown in — By chapter section. Starting with Review Ques- the Student Interactive Activity list. tions to test basic conceptual understanding, fol- lowed by Problems to test the student’s skill in A Look Ahead provides the student with an overview solving problems for that particular section of of concepts that will be presented in the chapter. the chapter. — Additional Problems uses knowledge gained from Tools to Use for Studying the various sections and/or previous chapters to Useful aids for studying are plentiful in Chemistry and solve the problem. should be used constantly to reinforce the comprehension — The Special Problem section contains more challeng- of chemical concepts. ing problems that are suitable for group projects.  Preface xxiii Real-Life Relevance Assign algorithmic questions providing students with multiple chances to practice and gain skill at Interesting examples of how chemistry applies to life are problem solving on the same concept. used throughout the text. Analogies are used where ap- propriate to help foster understanding of abstract chemi- Track Student Progress cal concepts. Assignments are automatically graded. End-of-Chapter Problems pose many relevant Gradebook functionality enables full course manage- questions for the student to solve. Examples include: ment including: Why do swimming coaches sometimes place a drop of alcohol in a swimmer’s ear to draw out water? — Dropping the lowest grades How does one estimate the pressure in a carbonated — Weighting grades/manually adjusting grades soft drink bottle before removing the cap? — Exporting your gradebook to Excel, WebCT, or BlackBoard Chemistry in Action boxes appear in every chapter — Manipulating data, enabling you to track student on a variety of topics, each with its own story of how progress through multiple reports chemistry can affect a part of life. The student can learn about the science of scuba diving and nuclear Offers More Flexibility medicine, among many other interesting cases. Sharing Course Materials with Colleagues— Chemical Mystery poses a mystery case to the stu- Instructors can create and share course materials and dent. A series of chemical questions provide clues as assignments with colleagues with a few clicks of the to how the mystery could possibly be solved. Chem- mouse, allowing for multiple section courses with ical Mystery will foster a high level of critical think- many instructors (and TAs) to continually be in sync ing using the basic problem-solving steps built-up if desired. throughout the text. Integration with BlackBoard or WebCT—once a Instructor’s Resources student is registered in the course, all student activity within McGraw-Hill’s ARIS is automatically re- ARIS (Assessment, Review, and corded and available to the instructor through a fully Instruction System) integrated grade book that can be downloaded to The Assessment, Review, and Instruction System, also Excel, WebCT, or BlackBoard. known as ARIS, is an electronic homework and course Access to your book, access to all books! The Presen- management system designed for greater flexibility, power, tation Center library includes thousands of assets from and ease of use than any other system. Whether you are many McGraw-Hill titles. This ever-growing resource looking for a preplanned course or one you can customize gives instructors the power to utilize assets specific to an to fit your course needs, ARIS is your solution. adopted textbook as well as content from all other books In addition to having access to all student digital learn- in the library. ing objects, ARIS enables instructors to build assignments Nothing could be easier! Accessed from the instruc- and track student progress, and provides more flexibility. tor side of your textbook’s ARIS website, Presentation Center’s dynamic search engine enables you to explore Build Assignments by discipline, course, textbook chapter, asset type, or Choose from prebuilt assignments or create your keyword. Simply browse, select, and download the files own custom content by importing your own content you need to build engaging course materials. All assets or editing an existing assignment from the prebuilt are copyrighted by McGraw-Hill Higher Education but assignment. can be used by instructors for classroom purposes. Assignments can include quiz questions, animations, Instructors: To access ARIS, request registration infor- and videos—anything found on the website. mation from your McGraw-Hill sales representative. Create announcements and utilize full course or indi- vidual student communication tools. Presentation Center Assign questions developed following the problem- Accessed from your textbook’s ARIS website, Presenta- solving strategy used within the textual material, en- tion Center is an online digital library containing photos, abling students to continue the learning process from artwork, animations, and other media types that can be the text into their homework assignments in a struc- used to create customized lectures, visually enhanced tured manner. tests and quizzes, compelling course websites, or attractive xxiv Preface printed support materials. All assets are copyrighted by Instructor’s Solution Manual McGraw-Hill Higher Education, but can be used by in- The Instructor’s Solution Manual is written by Brandon J. structors for classroom purposes. The visual resources in Cruickshank (Northern Arizona University) and Raymond this collection include: Chang. The solutions to all of the end-of-chapter prob- Art Full-color digital files of all illustrations in the lems are given in the manual. The manual also provides book can be readily incorporated into lecture presen- the difficulty level and category type for each problem. tations, exams, or custom-made classroom materials. This manual is online in the text’s ARIS website. In addition, all files are preinserted into PowerPoint The Instructor’s Manual provides a brief summary slides for ease of lecture preparation. of the contents of each chapter, along with the learning Photos The photos collection contains digital files goals, reference to background concepts in earlier chap- of photographs from the text, which can be repro- ters, and teaching tips. This manual is online in the text’s duced for multiple classroom uses. ARIS website. Tables Every table that appears in the text has been saved in electronic form for use in classroom presen- Content Delivery Flexibility tations and/or quizzes. Chemistry by Raymond Chang is available in many for- Animations Numerous full-color animations illus- mats in addition to the traditional textbook to give in- trating important processes are also provided. Har- structors and students more choices when deciding on the ness the visual impact of concepts in motion by format of their chemistry text. Choices include: importing these files into classroom presentations or online course materials. Color Custom by Chapter Media Player The chapter summary and many For even more flexibility, we offer the Chang Chemistry animations can be downloaded to a media player for text in a full-color, custom version that enables instruc- ease of study on the go. tors to pick the chapters they want. Students pay for only what the instructor chooses. Also residing on your textbook’s ARIS website are PowerPoint Lecture Outlines Ready-made pre- Electronic Book sentations that combine art and lecture notes are pro- If you or your students are ready for an alternative ver- vided for each chapter of the text. sion of the traditional textbook, McGraw-Hill can pro- PowerPoint Slides For instructors who prefer to vide you innovative and inexpensive electronic textbooks. create their lectures from scratch, all illustrations, By purchasing E-books from McGraw-Hill, students can photos, and tables are preinserted by chapter into save as much as 50% on selected titles delivered on an blank PowerPoint slides. advanced E-book platform. E-books from McGraw-Hill are smart, interactive, Computerized Test Bank Online searchable, and portable. There is a powerful suite of built-in tools that enable detailed searching, highlight- A comprehensive bank of test questions, revised by Ken ing, note taking, and student-to-student or instructor- Goldsby (Florida State University), is provided within a to-student note sharing. In addition, the media-rich computerized test bank enabling you to create paper and E-book for Chemistry integrates relevant animations online tests or quizzes in this easy-to-use program. and videos into the textbook content for a true multi- Imagine being able to create and access your test or quiz media learning experience. E-books from McGraw-Hill anywhere, at any time. will help students study smarter and quickly find the Instructors can create or edit questions, and drag-and information they need. And they will save money. Con- drop questions to create tests quickly and easily. The test tact your McGraw-Hill sales representative to discuss can be published automatically online to your course and E-book packaging options. course management system, or you can print them for paper-based tests. The test bank contains over 2000 multiple-choice Primis LabBase and short-answer questions. The questions, which are The Primis LabBase is by Joseph Lagowski (the Univer- graded in difficulty, are comparable to the problems in sity of Texas at Austin). More than 40 general chemistry the text. experiments are available in this database collection of  Preface xxv general lab experiments from the Journal of Chemical Chang. This supplement contains detailed solutions and ex- Education and experiments used by Professor Lagowski planations for all even-numbered problems in the main text. at the University of Texas at Austin, enabling instructors The manual also includes a detailed discussion of different to customize their lab manuals. types of problems and approaches to solving chemical prob- lems and tutorial solutions for many of the end-of-chapter problems in the text, along with strategies for solving them. Cooperative Chemistry Laboratory Manual This innovative guide by Melanie Cooper (Clemson Uni- versity) features open-ended problems designed to simu- Student Study Guide late experience in a research lab. Working in groups, This valuable ancillary by Kim Woodrum (University of students investigate one problem over a period of several Kentucky) contains material to help the student practice weeks, so that they might complete three or four projects problem-solving skills. For each section of a chapter, the during the semester, rather than one preprogrammed ex- author provides study objectives and a summary of the periment per class. The emphasis is on experimental design, corresponding text. Following the summary are sample analysis problem solving, and communication. problems with detailed solutions. Each chapter has true- false questions and a self-test, with all answers provided at the end of the chapter. Student Resources Designed to help students maximize their learning expe- rience in chemistry—we offer the following options to Schaum’s Outline of College Chemistry students: This helpful study aid by Jerome Rosenberg (Michigan State University) and Lawrence Epstein (University of Pittsburgh) provides students with hundreds of solved and ARIS supplementary problems for the general chemistry course. ARIS (Assessment, Review, and Instruction System) is an electronic study system that offers students a digital portal of knowledge. Acknowledgements Students can readily access a variety of digital learn- ing objects that include: I would like to thank the following reviewers and sympo- sium participants whose comments were of great help to chapter-level quizzing me in preparing this revision: animations Michael Abraham University of Oklahoma interactives Michael Adams Xavier University of Louisiana Media Player downloads of selected content Elizabeth Aerndt Community College of Rhode Island Francois Amar University of Maine Intelligent Tutors Taweechai Amornsakchai, Mahidol University Intelligent Tutors, powered by Quantum Tutors, provides Dale E. Arrington Colorado School of Mines real-time personal tutoring help for struggling and ad- Mufeed M. Basti North Carolina A&T State University vanced students with step-by-step feedback and detailed Laurance Beauvais San Diego State University instruction based on the student’s own work. Immediate Vladimir Benin University of Dayton answers are provided to the student over the Internet, day or night, on topics including chemical reactions, chemical Miriam Bennett San Diego State University bonding, equation balancing, equilibrium, oxidation Christine V. Bilicki Pasadena City College numbers, stoichiometry, and more. Intelligent Tutors can John J. Blaha Columbus State Community College be accessed through the ARIS book site. Mary Jo Bojan Pennsylvania State University Steve Boone Central Missouri State University Student Solutions Manual Timothy Brewer Eastern Michigan University The Student Solutions Manual is written by Brandon J. Michelle M. Brooks College of Charleston Cruickshank (Northern Arizona University) and Raymond Philip Brucat University of Florida xxvi Preface John D. Bugay Kilgore College Jongho Jun, Konkuk University Maureen Burkhart Georgia Perimeter College Jeffrey Keaffaber University of Florida William Burns Arkansas State University Michael Keck Emporia State University Stuart Burris Western Kentucky University MyungHoon Kim Georgia Perimeter College Les Butler Louisiana State University Jesudoss Kingston Iowa State University Bindu Chakravarty Houston Community College Pamela Kraemer Northern Virginia Community College Liwei Chen Ohio University Bette A. Kreuz University of Michigan–Dearborn Tom Clausen University of Alaska–Fairbanks Jothi V. Kumar North Carolina A&T State University Allen Clabo Francis Marion University Joseph Kushick Amherst College Barbara Cole University of Maine Richard H. Langley Stephen F. Austin State University W. Lin Coker III Campbell University William Lavell Camden County College Darwin Dahl Western Kentucky University Daniel B. Lawson University of Michigan–Dearborn Erin Dahlke Loras College Young Sik Lee, Kyung Hee University Gary DeBoer LeTourneau University Clifford LeMaster Ball State University Dawn De Carlo University of Northern Iowa Neocles Leontis Bowling Green State University Richard Deming California State University–Fullerton Alan F. Lindmark Indiana University Northwest Gregg Dieckman University of Texas at Dallas Teh Yun Ling, NUS High School of Maths and Science Michael Doughty Southeastern Louisiana University Arthur Low Tarleton State University Bill Durham University of Arkansas Jeanette Madea Broward Community College David Easter Texas State University–San Marcos Steve Malinak Washington Jefferson College Deborah Exton University of Oregon Diana Malone Clarke College David Frank California State University–Fresno C. Michael McCallum University of the Pacific John Gelder Oklahoma State University Lisa McCaw University of Central Oklahoma Leanna C. Giancarlo University of Mary Washington Danny McGuire Carmeron University Kenneth Goldsby Florida State University Scott E. McKay Central Missouri State University Eric Goll Brookdale Community College John Milligan Los Angeles Valley College John Gorden Auburn University Jeremy T. Mitchell-Koch Emporia State University Todor Gounev University of Missouri–Kansas City John Mitchell University of Florida Thomas Gray University of Wisconsin–Whitewater John T. Moore Stephan F. Austin State University Alberto Haces Florida Atlantic University Bruce Moy College of Lake County Michael Hailu Columbus State Community College Richard Nafshun Oregon State University Randall Hall Louisiana State University Jim Neilan Volunteer State Community College Ewan Hamilton Ohio State University at Lima Glenn S. Nomura Georgia Perimeter College Gerald Handschuh Kilgore College Frazier Nyasulu Ohio University Michael A. Hauser St. Louis Community College MaryKay Orgill University of Nevada–Las Vegas Daniel Lee Heglund South Dakota School of Mines Jason Overby College of Charleston Brad Herrick Colorado School of Mines M. Diane Payne Villa Julie College Huey Hoon HNG, Nanyang Technological University Lester L. Pesterfield Western Kentucky University Byron E. Howell Tyler Junior College Richard Petersen University of Memphis Lee Kim Hun, NUS High School of Math and Science Joanna Piotrowska Normandale Community College Tara Hurt East Mississippi Community College Amy Pollock Michigan State University–East Lansing Wendy Innis-Whitehouse University of Texas at William Quintana New Mexico State University Pan American Edward Quitevis Texas Tech University  Preface xxvii Jeff Rack Ohio University Special thanks are due to the following individuals Lisa Reece Ozarks Technical Community College for their detailed comments and suggestions for specific Michelle Richards-Babb West Virginia University chapters. Jim D. Roach Emporia State University Mufeed Basti North Carolina A&T Rojrit Rojanathanes, Chulalongkorn University Ken Goldsby Florida State University Steve Rowley Middlesex County College John Hagen California Polytechnic University Kresimir Rupnik Louisiana State University Joseph Keane Muhlenberg College Somnath Sarkar Central Missouri State University Richard Nafshun Oregon State University Jerry Sarquis Miami University Michael Ogawa Bowling Green State University Susan Scheble Metropolitan State College of Denver Jason Overby College of Charleston Raymond Scott University of Mary Washington John Pollard University of Arizona Thomas Selegue Pima Community College William Quintana New Mexico State University Sheila R. Smith University of Michigan–Dearborn Troy Wood University of Buffalo David Speckhard Loras College Kim Woodrum University of Kentucky Rick Spinney Ohio State University I would also like to thank Dr. Enrique Peacock- David Son Southern Methodist University Lopez and Desire Gijima for the computer-generated Larry O. Spreer University of the Pacific molecular orbital diagrams in Chapter 10. Shane Street University of Alabama As always, I have benefited much from discussions Satoshi Takara University of Hawaii with my colleagues at Williams College and correspon- dence with many instructors here and abroad. Kimberly Trick University of Dayton It is a pleasure to acknowledge the support given to Bridget Trogden Mercer University me by the following members of McGraw-Hill’s College Cyriacus Uzomba Austin Community College Division: Tammy Ben, Doug Dinardo, Chad Grall, Kara John B. Vincent University of Alabama Kudronowicz, Mary Jane Lampe, Marty Lange, Michael Thomas Webb Auburn University Lange, Kent Peterson, and Kurt Strand. In particular, I Lyle Wescott University of Mississippi would like to mention Gloria Schiesl for supervising the production, David Hash for the book design, John Leland Wayne Wesolowski University of Arizona for photo research, Daryl Bruflodt and Judi David for the Ken Williams Francis Marion University media, and Todd Turner, the marketing manager for his W.T. Wong, The University of Hong Kong suggestions and encouragement. I also thank my sponsor- Troy Wood University of Buffalo ing editor, Tami Hodge, and publisher, Thomas Timp, for Gloria A. Wright Central Connecticut State University their advice and assistance. Finally, my special thanks go Stephanie Wunder Temple University to Shirley Oberbroeckling, the developmental editor, for her care and enthusiasm for the project, and supervision Christine Yerkes University of Illinois at every stage of the writing of this edition. Timothy Zauche University of Wisconsin–Platteville William Zoller University of Washington —Raymond Chang  Study Tools Chapter opening page: Set yourself up for success by reviewing the chapter outline. Review “A Look Ahead” to famil- iarize yourself with the chapter concepts. Enhance your learning by utilizing the list of media available for the chapter. xxviii  Visuals: Understand the chemical principles though the various styles of visual aids and breakdown of important concepts. Problem Solving Tools Examples: Master problem-solving and think through prob- lems logically and systematically. Review of Concepts: Check your understanding by using the Review of Concepts tool found after appropriate chapter sections. xxix  Problems at the end of the chapter: Practice your skill and knowledge of concepts by working problems found at the end of each chapter. End of Chapter: Test your knowledge in preparation for exams by utilizing these tools: Key Equations, Summary, Key Words, Electronic Homework, Questions and Problems xxx Media Tools Animations: Understand major concepts by viewing animations developed specifically to reinforce the text content. Media Player: Learn on the fly by downloading text-specific content to your Media Player. Practice Problem from Examples TEXT problem Electronic Homework problem Test your knowledge using ARIS, the McGraw-Hill solu- tion to electronic homework. This system was developed using time-tested in-chapter and end-of-chapter problems from Chang 10th edition. The author’s “voice” is carried from the textbook questions to those found in the ARIS homework solutions. Quantum Tutors: just like working with a human tutor! Get homework help 24/7. xxxi G eneral chemistry is commonly perceived to be At the end of each chapter, you will find a summary more difficult than most other subjects. There is of facts and concepts, the key equations, and a list some justification for this perception. For one of key words, all of which will help you review for thing, chemistry has a very specialized vocabulary. At exams. first, studying chemistry is like learning a new language. Definitions of the key words can be studied in con- Furthermore, some of the concepts are abstract. Never- text on the pages cited in the end-of-chapter list or in theless, with diligence you can complete this course suc- the glossary at the back of the book. cessfully, and you might even enjoy it. Here are some ARIS houses an extraordinary amount of resources. suggestions to help you form good study habits and mas- Go to www.mhhe.com/physsci/chemistry/chang and ter the material in this text. click on the appropriate cover to explore animations, Attend classes regularly and take careful notes. download content to your Media Player, do your If possible, always review the topics discussed in homework electronically, and more. class the same day they are covered in class. Use this Careful study of the worked-out examples in the book to supplement your notes. body of each chapter will improve your ability to Think critically. Ask yourself if you really under- analyze problems and correctly carry out the calcula- stand the meaning of a term or the use of an equation. tions needed to solve them. Also take the time to A good way to test your understanding is to explain work through the practice exercise that follows each a concept to a classmate or some other person. example to be sure you understand how to solve the Do not hesitate to ask your instructor or your teach- type of problem illustrated in the example. The an- ing assistant for help. swers to the practice exercises appear at the end of the chapter, following the end-of-chapter problems. The tenth edition tools for Chemistry are designed to en- For additional practice, you can turn to similar prob- able you to do well in your general chemistry course. The lems referred to in the margin next to the example. following guide explains how to take full advantage of The questions and problems at the end of the chapter the text, technology, and other tools. are organized by section. Before delving into the chapter, read the chapter out- The back inside cover shows a list of important fig- line and the chapter introduction to get a sense of the ures and tables with page references. This index important topics. Use the outline to organize your makes it convenient to quickly look up information note taking in class. when you are solving problems or studying related Use the Student Interactive Activity as a guide to re- subjects in different chapters. view challenging concepts in motion. The anima- tions, media player content, and electronic homework If you follow these suggestions and stay up-to-date including tutorials are valuable in presenting a con- with your assignments, you should find that chemistry is cept and enabling the student to manipulate or choose challenging, but less difficult and much more interesting steps so full understanding can happen. than you expected. —Raymond Chang xxxii CHEMISTRY Chemistry The Study of Change A hydrogen-filled balloon exploding when heated with a flame. The hydrogen gas reacts with oxygen in air to form water vapor. Chemistry is the study of the properties of matter and the changes it undergoes. The models show hydrogen, oxygen, and water molecules.  Chapter Outline A Look Ahead We begin with a brief introduction to the study of chemistry and describe its role in our modern society. (1.1 and 1.2) 1.1 Chemistry: A Science for the Twenty-First Century Next, we become familiar with the scientific method, which is a systematic approach to research in all scientific disciplines. (1.3) 1.2 The Study of Chemistry 1.3 The Scientific Method We define matter and note that a pure substance can either be an element or a compound. We distinguish between a homogeneous mixture and a het- 1.4 Classifications of Matter erogeneous mixture. We also learn that, in principle, all matter can exist in one of three states: solid, liquid, and gas. (1.4 and 1.5) 1.5 The Three States of Matter 1.6 Physical and Chemical To characterize a substance, we need to know its physical properties, which can be observed without changing its identity and chemical properties, which Properties of Matter can be demonstrated only by chemical changes. (1.6) 1.7 Measurement Being an experimental science, chemistry involves measurements. We learn the basic SI units and use the SI-derived units for quantities like volume and 1.8 Handling Numbers density. We also become familiar with the three temperature scales: Celsius, 1.9 Dimensional Analysis in Fahrenheit, and Kelvin. (1.7) Solving Problems Chemical calculations often involve very large or very small numbers and a convenient way to deal with these numbers is the scientific notation. In calculations or measurements, every quantity must show the proper number of significant figures, which are the meaningful digits. (1.8) Finally, we learn that dimensional analysis is useful in chemical calculations. By carrying the units through the entire sequence of calculations, all the units will cancel except the desired one. (1.9) Student Interactive Activity C hemistry is an active, evolving science that has vital importance to our world, in both the realm of nature and the realm of society. Its roots are ancient, but as we will see, chemistry is every bit a modern science. We will begin our study of chemistry at the macroscopic level, where we Media Player can see and measure the materials of which our world is made. In this chapter, Chapter Summary we will discuss the scientific method, which provides the framework for research ARIS not only in chemistry but in all other sciences as well. Next we will discover Example Practice Problems how scientists define and characterize matter. Then we will spend some time End of Chapter Problems learning how to handle numerical results of chemical measurements and solve numerical problems. In Chapter 2, we will begin to explore the microscopic world Quantum Tutors of atoms and molecules. End of Chapter Problems 3 4 Chemistry: The Study of Change 1.1 Chemistry: A Science for the Twenty-First Century Chemistry is the study of matter and the changes it undergoes. Chemistry is often called the central science, because a basic knowledge of chemistry is essential for students of biology, physics, geology, ecology, and many other subjects. Indeed, it is central to our way of life; without it, we would be living shorter lives in what we would consider primitive conditions, without automobiles, electricity, computers, CDs, and many other everyday conveniences. Although chemistry is an ancient science, its modern foundation was laid in the The Chinese characters for chemistry nineteenth century, when intellectual and technological advances enabled scientists to mean “The study of change.” break down substances into ever smaller components and consequently to explain many of their physical and chemical characteristics. The rapid development of increas- ingly sophisticated technology throughout the twentieth century has given us even greater means to study things that cannot be seen with the naked eye. Using comput- ers and special microscopes, for example, chemists can analyze the structure of atoms and molecules—the fundamental units on which the study of chemistry is based—and design new substances with specific properties, such as drugs and environmentally friendly consumer products. As we enter the twenty-first century, it is fitting to ask what part the central sci- ence will have in this century. Almost certainly, chemistry will continue to play a pivotal role in all areas of science and technology. Before plunging into the study of matter and its transformation, let us consider some of the frontiers that chemists are currently exploring (Figure 1.1). Whatever your reasons for taking general chemistry, a good knowledge of the subject will better enable you to appreciate its impact on society and on you as an individual. Health and Medicine Three major advances in the past century have enabled us to prevent and treat diseases. They are public health measures establishing sanitation systems to protect vast num- bers of people from infectious disease; surgery with anesthesia, enabling physicians to cure potentially fatal conditions, such as an inflamed appendix; and the introduction of vaccines and antibiotics that make it possible to prevent diseases spread by microbes. Gene therapy promises to be the fourth revolution in medicine. (A gene is the basic unit of inheritance.) Several thousand known conditions, including cystic fibrosis and hemophilia, are carried by inborn damage to a single gene. Many other ailments, such as cancer, heart disease, AIDS, and arthritis, result to an extent from impairment of one or more genes involved in the body’s defenses. In gene therapy, a selected healthy gene is delivered to a patient’s cell to cure or ease such disorders. To carry out such a procedure, a doctor must have a sound knowledge of the chemical properties of the molecular components involved. The decoding of the human genome, which com- prises all of the genetic material in the human body and plays an essential part in gene therapy, relies largely on chemical techniques. Chemists in the pharmaceutical industry are researching potent drugs with few or no side effects to treat cancer, AIDS, and many other diseases as well as drugs to increase the number of successful organ transplants. On a broader scale, improved understanding of the mechanism of aging will lead to a longer and healthier life span for the world’s population. Energy and the Environment Energy is a by-product of many chemical processes, and as the demand for energy continues to increase, both in technologically advanced countries like the United  1.1 Chemistry: A Science for the Twenty-First Century 5 (a) (b) (c) (d) Figure 1.1 (a) The output from an automated DNA sequencing machine. Each lane displays the sequence (indicated by different colors) obtained with a separate DNA sample. (b) Photovoltaic cells. (c) A silicon wafer being processed. (d) The leaf on the left was taken from a tobacco plant that was not genetically engineered but was exposed to tobacco horn worms. The leaf on the right was genetically engineered and is barely attacked by the worms. The same technique can be applied to protect the leaves of other types of plants. States and in developing ones like China, chemists are actively trying to find new energy sources. Currently the major sources of energy are fossil fuels (coal, petroleum, and natural gas). The estimated reserves of these fuels will last us another 50–100 years, at the present rate of consumption, so it is urgent that we find alternatives. Solar energy promises to be a viable source of energy for the future. Every year Earth’s surface receives about 10 times as much energy from sunlight as is contained in all of the known reserves of coal, oil, natural gas, and uranium combined. But much of this energy is “wasted” because it is reflected back into space. For the past 30 years, intense research efforts have shown that solar energy can be harnessed effectively in two ways. One is the conversion of sunlight directly to electricity using devices called photovoltaic cells. The other is to use sunlight to obtain hydrogen from water. The hydrogen can then be fed into a fuel cell to generate electricity. Although our understanding of the scientific process of converting solar energy to electricity has advanced, the technology has not yet improved to the point where we can produce electricity on a large scale at an economically acceptable cost. By 2050, however, it has been predicted that solar energy will supply over 50 percent of our power needs. 6 Chemistry: The Study of Change Another potential source of energy is nuclear fission, but because of environmental concerns about the radioactive wastes from fission processes, the future of the nuclear industry in the United States is uncertain. Chemists can help to devise better ways to dispose of nuclear waste. Nuclear fusion, the process that occurs in the sun and other stars, generates huge amounts of energy without producing much dangerous radioactive waste. In another 50 years, nuclear fusion will likely be a significant source of energy. Energy production and energy utilization are closely tied to the quality of our environment. A major disadvantage of burning fossil fuels is that they give off carbon dioxide, which is a greenhouse gas (that is, it promotes the heating of Earth’s atmosphere), along with sulfur dioxide and nitrogen oxides, which result in acid rain and smog. (Harnessing solar energy has no such detrimental effects on the environ- ment.) By using fuel-efficient automobiles and more effective catalytic converters, we should be able to drastically reduce harmful auto emissions and improve the air quality in areas with heavy traffic. In addition, electric cars, powered by durable, long-lasting batteries, and hybrid cars, powered by both batteries and gasoline, should become more prevalent, and their use will help to minimize air pollution. Materials and Technology Chemical research and development in the twentieth century have provided us with new materials that have profoundly improved the quality of our lives and helped to advance technology in countless ways. A few examples are polymers (including rubber and nylon), ceramics (such as cookware), liquid crystals (like those in electronic displays), adhesives (used in your Post-It notes), and coatings (for example, latex paint). What is in store for the near future? One likely possibility is room-temperature superconductors. Electricity is carried by copper cables, which are not perfect conduc- tors. Consequently, about 20 percent of electrical energy is lost in the form of heat between the power station and our homes. This is a tremendous waste. Superconductors are materials that have no electrical resistance and can therefore conduct electricity with no energy loss. Although the phenomenon of superconductivity at very low temperatures (more than 400 degrees Fahrenheit below the freezing point of water) has been known for over 90 years, a major breakthrough in the mid-1980s demonstrated that it is pos- sible to make materials that act as superconductors at or near room temperature. Chem- ists have helped to design and synthesize new materials that show promise in this quest. The next 30 years will see high-temperature superconductors being applied on a large scale in magnetic resonance imaging (MRI), levitated trains, and nuclear fusion. If we had to name one technological advance that has shaped our lives more than any other, it would be the computer. The “engine” that drives the ongoing computer revolution is the microprocessor—the tiny silicon chip that has inspired countless inventions, such as laptop computers and fax machines. The performance of a micro- processor is judged by the speed with which it carries out mathematical operations, such as addition. The pace of progress is such that since their introduction, micro- processors have doubled in speed every 18 months. The quality of any microprocessor depends on the purity of the silicon chip and on the ability to add the desired amount of other substances, and chemists play an important role in the research and develop- ment of silicon chips. For the future, scientists have begun to explore the prospect of “molecular computing,” that is, replacing silicon with molecules. The advantages are that certain molecules can be made to respond to light, rather than to electrons, so that we would have optical computers rather than electronic computers. With proper genetic engineering, scientists can synthesize such molecules using microorganisms instead of large factories. Optical computers also would have much greater storage capacity than electronic computers.  1.2 The Study of Chemistry 7 Food and Agriculture How can the world’s rapidly increasing population be fed? In poor countries, agricultural activities occupy about 80 percent of the workforce, and half of an average family bud- get is spent on foodstuffs. This is a tremendous drain on a nation’s resources. The factors that affect agricultural production are the richness of the soil, insects and diseases that damage crops, and weeds that compete for nutrients. Besides irrigation, farmers rely on fertilizers and pesticides to increase crop yield. Since the 1950s, treatment for crops suf- fering from pest infestations has sometimes been the indiscriminate application of potent chemicals. Such measures have often had serious detrimental effects on the environment. Even the excessive use of fertilizers is harmful to the land, water, and air. To meet the food demands of the twenty-first century, new and novel approaches in farming must be devised. It has already been demonstrated that, through biotechnol- ogy, it is possible to grow larger and better crops. These techniques can be applied to many different farm products, not only for improved yields, but also for better frequency, that is, more crops every year. For example, it is known that a certain bacterium produces a protein molecule that is toxic to leaf-eating caterpillars. Incor- porating the gene that codes for the toxin into crops enables plants to protect them- selves so that pesticides are not necessary. Researchers have also found a way to prevent pesky insects from reproducing. Insects communicate with one another by emitting and reacting to special molecules called pheromones. By identifying and synthesizing pheromones used in mating, it is possible to interfere with the normal reproductive cycle of common pests; for example, by inducing insects to mate too soon or tricking female insects into mating with sterile males. Moreover, chemists can devise ways to increase the production of fertilizers that are less harmful to the envi- ronment and substances that would selectively kill weeds. 1.2 The Study of Chemistry Compared with other subjects, chemistry is commonly believed to be more difficult, at least at the introductory level. There is some justification for this perception; for one thing, chemistry has a very specialized vocabulary. However, even if this is your first course in chemistry, you already have more familiarity with the subject than you may realize. In everyday conversations we hear words that have a chemical connection, although they may not be used in the scientifically correct sense. Examples are “elec- tronic,” “quantum leap,” “equilibrium,” “catalyst,” “chain reaction,” and “critical mass.” Moreover, if you cook, then you are a practicing chemist! From experience gained in the kitchen, you know that oil and water do not mix and that boiling water left on the stove will evaporate. You apply chemical and physical principles when you use baking soda to leaven bread, choose a pressure cooker to shorten the time it takes to prepare soup, add meat tenderizer to a pot roast, squeeze lemon juice over sliced pears to prevent them from turning brown or over fish to minimize its odor, and add vinegar to the water in which you are going to poach eggs. Every day we observe