Chemistry Books Chemistry

2018

Chemistry for Engineering Students, 4th Edition

Lawrence S. Brown
Texas A&M University, College Station

Thomas Holme
Iowa State University, taholme@iastate.edu

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Brown, Lawrence S. and Holme, Thomas, "Chemistry for Engineering Students, 4th Edition" (2018). Chemistry Books. 1.
https://lib.dr.iastate.edu/chem_books/1

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 Contents

Preface xv11
Student Introduction xxv1

1\ Introduction to Chemistry 1
1.1 1mna:11 Critical Materials 3
1.2 The Study of Chemistry 4
The Macroscopic Perspective 4
The Microscopic or Particulate Perspective 6
Symbolic Representation 9
1.3 The Science of Chemistry: Observations, Models,
and Systems 10
Observations in Science 10
Interpreting Observations 11
Models in Science 12
1.4 Numbers and Measurements in Chemistry 13
Units 13
Numbers and Significant Figures 16
1.s Problem Solving in Chemistry and Engineering 19
Using Ratios 19
Ratios in Chemistry Calculations 20
Conceptual Chemistry Problems 22
Visualization in Chemistry 23
1.6 1unm:11 Touchscreen Technology 2 5
Focus on Problem Solving 26
Summary 27
Key Terms 27
Problems and Exercises 28

\
2 Atoms and Molecules 33
2.1 1u11m:11 Conducting Polymers 34
2.2 Atomic Structure and Mass 36
Fundamental Concepts of the Atom 36
Atomic Number and Mass Number 37
Isotopes 37
Atomic Symbols 38
Atomic Masses and Weights 39
2.3 Ions 41
Mathematical Description 42
Ions and Their Properties 43

viii
 2.4 Compounds and Chemical Bonds 43
Chemical Formulas 44
Chemical Bonding 45
2.5 The Periodic Table 47
Periods and Groups 48
Metals, Nonmetals, and Metal/aids 50
2.6 Inorganic and Organic Chemistry 51
Inorganic Chemistry-Main Groups and Transition Metals 52
Organic Chemistry 53
Functional Groups 56
2.7 Chemical Nomenclature 56
Binary Systems 56
Naming Covalent Compounds 58
Naming Ionic Compounds 59
2.8 1m1ttt:11 Polyethylene 60
Focus on Problem Solving 62
Summary 63
Key Terms 63
Problems and Exercises 64

3\ M olecules, Moles, and Chemical

Equations 69
3.1 1m>t@:11 Biomass and Biofuel Engineering 70
3.2 Chemical Formulas and Equations 72
Writing Chemical Equations 72
Balancing Chemical Equations 73
3.3 Aqueous Solutions and Net Ionic Equations 78
Solutions, Solvents, and Solutes 79
Chemical Equations for Aqueous Reactions 81
Acid- Base Reactions 83
3.4 Interpreting Equations and the Mole 87
Interpreting Chemical Equations 87
Avogadro's Number and the Mole 87
Determining Molar Mass 89
3.5 Calculations Using Moles and Molar Masses 90
Elemental Analysis: Determining Empirical and Molecular
Formulas 92
Molarity 95
Dilution 96
3.6 llMM:ll Carbon Sequestration 97
Focus on Problem Solving 99
Summary 99
Key Terms 100
Problems and Exercises 100

4\ Stoichiometry 107
4.1 11.11•1@:11 Gasoline and Other Fuels 108

Contents ix
 4.2 Fundamentals of Stoichiometry 111
Obtaining Ratios from a Balanced Chemical Equation 112
4.3 L1m1ting Reactants 116
4.4 Theoretical and Percentage Yields 121
4.5 Solution Stoichiometry 123
4.6 1m1tct:11 Alternative Fuels and Fuel Add1t1ves 125
Focus on Problem Solving 127
Summary 128
Key Terms 128
Problems and Exercises 128

5\ Gases 137
5.1 llMM:ll Natural Gas Production 138
Properties of Gases 140
5.2 Pressure 141
Measuring Pressure 142
Units of Pressure 143
5.3 History and Application of the Gas Law 144
Units and the Ideal Gas Law 147
5.4 Partial Pressure 148
5.5 Stoichiometry of Reactions Involving Gases 151
STP Conditions 152
5.6 Kinetic-Molecular Theory and Ideal Versus Real
Gases 153
Postulates of the Model 154
Real Gases and Limitations of the Kinetic Theory 157
Correcting the Ideal Gas Equation 158
5.7 1m1ut:11 Gas Sensors 160
Capacitance Manometer 161
Thermocouple Gauge 161
Ionization Gauge 162
Mass Spectrometer 163
Focus on Problem Solving 163
Summary 164
Key Terms 164
Problems and Exercises 165

6 \ The Periodic Table and Atomic

Structure 171
6.1 1u11m:11 Trace Analysis 172
6.2 The Electromagnetic Spectrum 174
The Wave Nature of Light 174
The Particulate Nature of Light 179
6.3 Atomic Spectra 183
The Bohr Atom 185
6.4 The Quantum Mechanical Model of the Atom 186

x Contents
 Potential Energy and Orbitals 187
Quantum Numbers 188
Visualizing Orbitals 191
6.5 The Pauli Exclusion Principle and Electron
Configurations 194
Orbital Energies and Electron Configurations 194
Hund's Rule and the Aufbau Principle 196
6.6 The Periodic Table and Electron Configurations 198
6.7 Periodic Trends in Atomic Properties 199
Atomic Size 199
Ionization Energy 202
Electron Affinity 203
6.8 1£11'1M:JI Modern Light Sources: LEDs and Lasers 205
Focus on Problem Solving 207
Summary 208
Key Terms 208
Problems and Exercises 209

- 7\ Chemical Bonding and Molecular

Structure 215
7.1 IU"1ttt:ll Materials for Biomedical Engineering 216
7.2 The Ionic Bond 217
Formation of Cations 217
Formation of Anions 219
7.3 The Covalent Bond 221
Chemical Bonds and Energy 221
Chemical Bonds and Reactions 223
Chemical Bonds and the Structure of Molecules 223
7.4 Electronegativity and Bond Polarity 225
Electronegativity 225
Bond Polarity 226
7.5 Keeping Track of Bonding: Lewis Structures 229
Resonance 234
7.6 Orbital Overlap and Chemical Bonding 235
7.7 Hybrid Orbitals 237
7.8 Shapes of Molecules 239
7.9 •V"1M:ll Molecular-Scale Engineering for Drug
Delivery 246
Focus on Problem Solving 247
Summary 248
Key Terms 248
Problems and Exercises 249

8\ Molecules and Materials 253

8.1 11mm:11 Carbon 254
8.2 Condensed Phases-Solids 256

Contents xi
 8.3 Bonding in Solids: Metals, Insulators, and
Semiconductors 262
Models of Metallic Bonding 262
Band Theory and Conductivity 264
Semiconductors 265
8.4 Intermolecular Forces 269
Forces Between Molecules 269
Dispersion Forces 269
Dipole-Dipole Forces 270
Hydrogen Bonding 2 71
8.5 Condensed Phases-Liquids 274
Vapor Pressure 274
Boiling Point 276
Surface Tension 277
8.6 Polymers 278
Addition Polymers 279
Condensation Polymers 281
Copolymers 283
Physical Properties 284
Polymers and Additives 285
8.7 1m;na:11 Micro-Electrical-Mechanical Systems (MEMS) 285
Focus on Problem Solving 287
Summary 287
Key Terms 287
Problems and Exercises 288

9 \ Energy and Chemistry 293

9.1 1u11t11:11 Energy Use and the World Economy 294
9.2 Defining Energy 297
Forms of Energy 297
Heat and Work 298
Energy Units 298
9 .3 Energy Transformation and Conservation
of Energy 299
Waste Energy 301
9.4 Heat Capacity and Calorimetry 302
Heat Capacity and Specific Heat 302
Calorimetry 305
9.5 Enthalpy 307
Defining Enthalpy 307
6H of Phase Changes 308
Vaporization and Electricity Production 310
Heat of Reaction 311
Bonds and Energy 312
Heats of Reaction for Some Specific Reactions 313
9.6 Hess's Law and Heats of Reaction 313
Hess's Law 314
Formation Reactions and Hess's Law 316
9.7 Energy and Stoichiometry 318
Energy Density and Fuels 319

xii Contents
 9.8 IUJ1ltf:ll Power Distribution and the Electrical Grid 320
Focus on Problem Solving 322
Summary 323
Key Terms 323
Problems and Exercises 323

10 Entropy and the Second Law

of Thermodynamics 331
10.1 1m1@11 Recycling of Plastics 332
10.2 Spontaneity 333
Nature's Arrow 333
Spontaneous Processes 334
Enthalpy and Spontaneity 335
10.3 Entropy 335
Probability and Spontaneous Change 336
Definition of Entropy 337
Judging Entropy Changes in Processes 338
10.4 The Second Law of Thermodynamics 339
The Second Law 339
Implications and Applications 340
10.5 The Third Law of Thermodynamics 341
10.6 Gibbs Free Energy 343
Free Energy and Spontaneous Change 343
Free Energy and Work 346
10.7 Free Energy and Chemical Reactions 347
Implications of t.G 0 for a Reaction 348
10.8 11mm:11 The Economics of Recycling 349
Focus on Problem Solving 352
Summary 353
Key Terms 353
Problems and Exercises 353

11 Chemical Kinetics 361

11.1 IUJ>1td:ll Urban Air Pollution 362
11.2 Rates of Chemical Reactions 364
Concept of Rate and Rates of Reaction 364
Stoichiometry and Rate 365
Average Rate and Instantaneous Rate 366
11.3 Rate Laws and the Concentration Dependence
of Rates 368
The Rate Law 368
Determination of the Rate Law 369
11.4 Integrated Rate Laws 372
Zero-Order Integrated Rate Law 373
First-Order Integrated Rate Law 374
Second-Order Integrated Rate Law 376
Half-Life 379

Contents xiii
 11.s Temperature and Kinetics 380
Temperature Effects and Molecules That React 381
Arrhenius Behavior 383
11 .6 Reaction Mechanisms 388
Elementary Steps and Reaction Mechanisms 388
Mechanisms and Rate: The Rate-Determining Step 390
11 .1 Catalysis 391
Homogeneous and Heterogeneous Catalysts 391
~ Molecular Perspective of Catalysis 393
~
< Catalysis and Process Engineering 393

-~-----1 11 .s 11mttt:11 Air Quality Monitoring 394

Focus on Problem Solving 396
Summary 397
Key Terms 397
Problems and Exercises 398

1~ Chemical Equilibrium 407

12.1 IUJ'1&:11 Concrete Production and Weathering 408
12.2 Chemical Equilibrium 410
Forward and Reverse Reactions 41 O
Mathematical Relationships 412
12.3 Equilibrium Constants 414
The Equilibrium (Mass Action) Expression 414
Gas Phase Equilibria: KP vs. Kc 415
Homogeneous and Heterogeneous Equilibria 416
Numerical Importance of the Equilibrium Expression 41 7
Mathematical Manipulation of Equilibrium Constants 418
Reversing the Chemical Equation 418
Adjusting the Stoichiometry of the Chemical Reaction 419
Equilibrium Constants for a Series of Reactions 420
Units and the Equilibrium Constant 421
12.4 Equilibrium Concentrations 421
Equilibrium Concentrations from Initial Concentrations 422
Mathematical Techniques for Equilibrium Calculations 425
12.s LeChatelier's Principle 426
Effect of a Change in Concentration of Reactant or Product on
Equilibrium 426
Effect of a Change in Pressure on Equilibrium When Gases Are
Present 428
Effect of a Change in Temperature on Equilibrium 430
Effect of a Catalyst on Equilibrium 431
12.G Solubility Equilibria 431
Solubility Product Constant 432
Defining the Solubility Product Constant 432
The Relationship Between Ksp and Molar Solubility 433
Common Ion Effect 434
Reliability of Using Molar Concentrations 435
12.7 Acids and Bases 436
The Br0nsted-Lowry Theory of Acids and Bases 436
The Role of Water m the Brensted- Lowry Theory 436

xiv Contents
 Weak Acids and Bases 437
Strong Acid-Strong Base Titrations 441
Weak Acid-Strong Base Titrations 443
12.8 Free Energy and Chemical Equilibrium 446
Graphical Perspective 446
Free Energy and Nonstandard Conditions 447
12.9 IL'HM:ll Bendable Concrete 449
Focus on Problem Solving 450
Summary 451
Key Terms 451
Problems and Exercises 451

13\ El ectrochemistry 459

13.1 1£1'1@11 Corrosion 460
13.2 Oxidation-Reduction Reactions and Galvanic Cells 461
Oxidation-Reduction and Half-Reactions 461
Building a Galvanic Cell 463
Terminology for Galvanic Cells 464
Atomic Perspective on Galvanic Cells 464
Galvanic Corrosion and Uniform Corrosion 465
13.3 Cell Potentials 467
Measuring Cell Potential 467
Standard Reduction Potentials 469
Cathodic Protection 472
Nonstandard Conditions 472
13.4 Cell Potentials and Equilibrium 474
Cell Potentials and Free Energy 474
Equilibrium Constants 475
13.S Batteries 476
Primary Cells 477
Secondary Cells 479
Fuel Cells 481
Limitations of Batteries 482
13.6 Electrolysis 482
Electrolysis and Polarity 482
Passive Electrolysis in Refining Aluminum 483
Active Electrolysis and Electroplating 484
13.7 Electrolysis and Stoichiometry 485
Current and Charge 485
Calculations Using Masses of Substances in Electrolysis 487
13.8 1mmta1 Batteries in Engineering Design 489
Focus on Problem Solving 491
Summary 492
Key Terms 492
Problems and Exercises 493

14 \ Nuclear Chemistry 499

14.1 IVHM:ll Cosmic Rays and Carbon Dating 500

Contents xv
 14.2 Radioactivity and Nuclear Reactions 501
Radioactive Decay 501
Alpha Decay 502
Beta Decay 503
Gamma Decay 504
Electron Capture 504
Positron Emission 505
14.3 Kinetics of Radioactive Decay 506
Radiocarbon Dating 508
14.4 Nuclear Stability 510
14.5 Energetics of Nuclear Reactions 512
Binding Energy 512
Magic Numbers and Nuclear Shells 513
14.6 Transmutation, Fission, and Fusion 514
Transmutation: Changing One Nucleus into Another 514
Fission 515
Nuclear Reactors 51 7
Nuclear Waste 518
Fusion 520
14.7 The Interaction of Radiation and Matter 521
Ionizing and Penetrating Power of Radiation 521
Methods of Detecting Radiation 522
Measuring Radiation Dose 523
14.8 1m;1@11 Modern Medical Imaging Methods 524
Focus on Problem Solving 525
Summary 526
Key Terms 526
Problems and Exercises 527

Appendixes
A International Table of Atomic Weights 533
B Physical Constants 535
C Electron Configurations of Atoms in the Ground State 536
D Physical Constants of Some Common Substances
Specific Heats and Hea t Capacities 537
Heats and Temperatures for Phase Changes 537
E Selected Thermodynamic Da ta at 298.15 K 538
F Ioniza tion Constants of Weak Acids at 25°C 544
G Ioniza tion Constants of Weak Bases at 25°C 546
H Solubility Product Constants of Some Inorganic Compounds
at 25°C 547
Standard Reduction Potentials in Aqueous Solution at 25°C 549
Standard Reduction Potentials in Aqueous Solution at 25°C 551
J Answers to Check your Understanding Exercises 552
K Answers to Odd-Numbered Problems and Exercises 555

Glossary 580

Index 592

xvi Contents
 Preface

\ The Audience for This Text

As chemists, we see connections between our subject and virtually everything. So the
idea that engineering students should learn chemistry strikes most chemists as self-
evident. But chemistry is only one of many sciences with which a practicing engineer
must be familiar, and the undergraduate curriculum must find room for many topics.
Hence, engineering curricula at more and more universities are shifting from the
traditional }ear-long general chemistry sequence to a single semester. And in most
cases, these schools are offering a separate one-term course designed specifically for
their engineering students. "When schools-including our own-originally began
offering these courses, there was no text on the market for them, so content from
two-semester texts had to be heavily modified to fit the course. Although it is pos-
sible to do this, it is far from ideal. It became apparent that a book specifically geared
for this shorter course was necessary. We have written this book to fill this need.
Our goal is to instill an appreciation for the role of chemistry in many areas of
engineering and technology and of the interplay between chemistry and engineering
in a variety of modern technologies. For most engineering students, the chemistry
course is primarily a prerequisite for courses involving materials properties. These
courses usually take a phenomenological approach to materials rather than empha-
sizing the chemist's molecular perspective. Thus one aim of this text is to provide
knowledge of and appreciation for the chemical principles of strucrure and bonding
that underpin materials science. This does not mean that we have written the book
as a materials science text, but rather that the text is intended to prepare students for
subsequent study in that area.
The book also provides sufficient background in the science of chemistry for a
technically educated professional. Engi neering, after all, is the creative and practical
application of a broad array of scientific principles, so its practitioners should have a
broad base in the natural sciences.

\ Content and Organization

The full scope of the traditional general chemistry course cannot be taught meaning-
fully in one semester or one or two quarters, so we have had to decide what content to
include. There are basically two models used to condense the general chemistry cur-
riculum. The first is to take the approach of an "essentials" book and reduce the depth
of coverage and the number of examples but retain nearly all of the traditional topics.
T he second is to make more difficult and fundamental decisions as to what chemistry
topics are proper and relevant to the audience- in this case, future engineers. We
chose the latter approach and built a 14-chapter book from the ground up to satisfy
what we think are the goals of the course:
• Provide a concise but thorough introduction to the science of chemistry.
• Give students a firm foundation in the principles of structure and bonding as a
foundation for further sn1dy of materials science.

xvii
 • Show the connection between molecular beha\ ior and observable physical
properties.
• Show the connections between chemistry and the other subjects studied b} t: lgi-
neering students, especially mathematics and physics.
Taken together, the 14 chapters in this book represent some\\ hat more material th ,
can comfortably fit into a standard semester course. Thus departments or indi, idual
instructors will need to make some further choices as to the content that is most ..uit-
able for their own students. We suspect that many instructors will not choose to in
elude all of the material on equilibrium in Chapter 12, for example. imilarly, we h 1 e
included more topics in Chapter 8, on condensed phases, than we expect most facult}
will include in their courses.

Topic Coverage
The coverage of topics in this text reflects the fact that chemists con-
stantly use multiple concepts to understand their field, often u ing more
than one model simultaneously. Thus the study of chemistry we pres-
ent here can be viewed from multiple perspectives: macroscopic, 1111 -
croscopic, and symbolic. The latter two perspecti\'es are emphasized in
Chapters 2 and 3 on atoms, molecules, and reactions. In Chapters 4 and
5, we establish more of the connection between micro copic and mac-
roscopic in our treatment of stoichiometry and gases. V.'e return to the
microscopic perspective to cover more details of atomic structure and
chemical bonding in Chapters 6 through 8. The energetic aspects of
chemistry, including important macroscopic consequences, are consid-
ered in Chapters 9 and 10, and kinetics and equilibrium are treated in
Chapters 11and12, respectively. C hapter 13 deals with electrochemistry and corro-
sion, an important chemistry application for many engineering disciplines. Finally, we
conclude with a discussion of nuclear chemistry.

Specific Content Coverage

v\Te know that there are specific topics in general chemistry that are vital to future
engineers. We've chosen to treat them in the following ways.
Organic Chem istry: Organic chemistry is important in many areas of engineering,
particularly as related to the properties of polymers. Rather than using a single or-
ganic chapter, we integrate our organic chemistry coverage over the entire text, fo-
cusing on polymers. We introduce organic polymers in Section 2.1 and use polymers
and their monomers in many examples in this chapter. Chapter 2 also contains a rich
discussion of organic line structures and functional groups and ends with a section
on the synthesis, structure, and properties of polyethylene. Chapter 4 opens and ends
with discussions of fuels, a topic to which we return in Chapter 9. Chapter 8 contains
more on carbon and polymers, and the recycling of polymers provides the context for
consideration of the second law of thermodynamics in Chapter 10.
Acid-Base Cheniistry: Acid-base reactions represent another important area of
chemistry with applications in engineering, and again we have integrated our cover-
age into appropriate areas of the text. Initially, we define acids and bases in conjunc-
tion with the introduction to solutions in Chapter 3. Simple solution stoichiometry
is presented in Chapter 4. Finally, a more detailed treaanent of acid-base chemistry
is presented in the context of equilibria in Chapter 12, and this section has been ex-
panded significantly in this edition.
Nuclear Chemistry: A chapter dealing with nuclear chemistry is included for those
\vishing to teach that topic. Coverage in this chapter includes fundamentals of nuclear

xviii Preface
 reactions, nuclear stability and radioactivity, decay kinetics, and the energetic conse-
quences of nuclear processes.
Mathematics: The math skills of students entering engineering majors generally
are stronger than those in the student body at large, and most of the students
taking a course of the type for which this book is intended will be concurrently
enrolled in an introductory ca lculus course. In light of this, we include re ferences
to the role of ca lculus where appropriate via our MathConnections boxes. These MathConnections
essays expand and review math concepts as they pertain to the particular topic
being studied, and appear wherever the links between the topic at hand and math-
ematics seems especially strong. These boxes are intended to be unobtrusive, so
those students takin g a precalculus math course will not be adversely affected. The
point of including calculus is not to raise the level of material being presented, but
rather to show the natural connections between the various subjects students are
studying.

lh'Htd:il

Connections Between
Chemistry and Engineering
Because this hook is intended for courses designed for engineering
majors, we stme to present chemistry in contexts that we feel will
appeal to the mterests of such students. Links between chemistry and
engineering are central to the structure of the text. Each chapter be-
gins and ends wi th a section ca ll ed llMld:ll, which introduces a
template or theme showing the interplay between chemistry and en-
gineering. These sections are only the beginning of the connections,
and the theme introduced in the initial Insight appears regularly
throughout that chapter.
We opt for currency in our engineering applications wherever possible, so
throughout the book, we discuss recent key innovations in various fields. For example,
Chapter 5 includes a discussion of hydraulic fracturing and natural gas recovery. In
Chapter 7, we describe mesoporous silicon nanoparticles, a front-line research topic
that may have important applications in biomedical engineering in the future. Chapter
8 closes with a discussion of the fabrication of micro-electrical-mechanical systems
(MEMS).

\ Approach to Problem Solving

Problem solving is a key part of college chemistry courses and is especially important
EXAMPLE PROBLEM
as a broadly transferable skill for engineering students. Accordingly, this text includes
worked problems throughout. All of our Example Problems include a Strategy section Strategy
immediately following the problem statement, in which we emphasize the concepts Analyze Your Answer
and relationships that must be considered to work the problem. After the solution, Discussion
we often include a section called Analyze Yotff Answer that is designed to help students Check Your Understanding
learn to estimate whether or not the answer they have obtained is reasonable. In many
examples, we also include Discussion sections that he lp explain the importance of a
problem solvi ng concept or point out common pitfalls to be avoided. Finally, each ex-
ample closes with a Check Jour U11demn11di11g problem or question to help the student
to generalize or extend what's been learned in the example problem.
\ Ve believe that the general chemistry experience should help engineering students
develop improved problem solving skills. i\foreover, we feel that those skills should be
transferable to other subjects in the engineering curriculum even though ch emistry

Preface xix
 content may not be involved. Accordingly, \\e include a unique feature at the end o f
Focus On Problem Solving each chapter called Forns on Problem Sofring. In these sections, the questio ns posed <lo
not require a numerical answer, but rather a k the rudent to identif) the s tr<ttefn c r
reasoning to be used in the problem and often require them to identif) missing infu r-
mation for the problem. In most cases, it is not pos ible to arrive at a final numerical
answer using the infon11ation pro\'ided, so students are forced to focus on de,·eloping
a solution rather than just identif)•ing and executing an algorithm. The end-of-chapter
exercises include additional problems of thi narure so the Focus 011 Problem oh wg can
be fully incorporated into the course. This fearure grew out of an l\ ' F-funded projec:t
on assessing problem soking in chemistry classes.

Text Features
\Ve employ a number of features, some of which we referred to earlier, to help stu-
dents see the utility of chemistry and understand the connections to engineering.
llM@:ll Sections Each chapter is built around a template called an !nStgbt. These
themes, which both open and close each chapter, have been chosen to shO\\ Case
connections between engineering and chemistry. In addition to the chapter opening
and closing sections, the template themes are woven throughout the chapter,
frequently providing the context for points of discussion or example problems. This
special Insight icon is used throughout the book to identify places\\ here ide,1s
presented in the chapter opening section are revisited in the narrative.
FOCUS ON PROBLEM SOLVING Sections Engineering faculties unanimou I} say th<ll
freshman engineering students need practice in olving problems. However, it is im
portant to make a distinction here between problems and exercises. Exercises pro-
vide a chance to practice a narrow skill, whereas problems require multiple steps and
thinking outside the context of the information given. Focus on Problem ofring offer'>
students the chance to develop and practice true problem solving skills. These sec-
tions, which appear at the end of every chapter, include a mix of quantitative and
qualitative questions that focus on the p1'0cess of finding a solution to a problem, not
the solution itself. \ Ve upport these by including additional similar problems in the
end-of-chapter material.
MathConnections In our experience, one trait that distinguishes engineering
students from other genera l chemistry students is a higher level of comfort with
mathematics. Typically, most students who take a class of the sort for which this book
has been \\Titten will also be taking a course in calculus. Thus it seems natural to us to
point out the mathematical underpinnings of several of the chemistry concepts pre-
sented in the text because this should help students forge mental connections between
their courses. At the same time, we recognize that a srudent taking a precalculus math
course should not be precluded from taking chemistry. To balance these concerns, we
have placed any advanced mathematics into special MathC011nectio11s sections, which
are set off from the body of the text. Our hope is that those students familiar with the
mathematics involved will benefit from seeing the origin of things such as integrated
rate laws, whereas those students with a less extensive background in math will still be
able to read the text and master the chemistry presented.

EXAMPLE PROBLEM Our examples are designed to illustrate good problem

soh·ing practices by first focusing on the reasoning behind the solution before moving
into any needed calculations. \Ve emphasize this "think first" approach by beginning
with a Strategy section, which outlines a plan of attack for the problem.\ Ve find that
many students are too quick to accept whatever answer their calculator might di pla).
To combat this, \~e follow most solutions with an Analyz e Your An.m·er section, which
uses estimation and other strategies to walk students through a double check of their

xx Preface
 answers. Every example closes with a Check Your Understanding exercise to allow stu-
dents to practice or extend the skill they have just learned. Answers to these additional
exercises are included in Appendix J at the end of the book.
End-of-Chapter Features Each chapter concludes with a chapter summary, outlining
the main points of the chapter, and a list of key te rms, each of which includes the
section number where the term first appeared. Definitions for all key terms appear in
the Glossary.
Problem Sets Each chapter includes roughly 100 problems and exercises, spanning
a wide range of difficulty. Most of these exercises are identified with specific sec-
tions to provide the practice that students need to master material from that section.
Most chapters also include a number of Additional Problems, which are not tied to any Additional Problems
particular section and which may incorporate ideas from multiple sections. Focus on Focus on Problem Solving
Problem So/toing exercises follow, as described earlier. The problems for most chap- Cumulative Problems
ters conclude '" ith Cumulative Problems, which ask students to synthesize information
from the current chapter with what they've learned from previous chapters to form
answers. For the fourth edition, we have added a new Conceptual Problems section, Conceptual Problems
which emphasizes molecular scale visualization and other nonalgorithmic exercises.
Answers for all odd-numbered problems appear at the end of the book in Appendix K.
Margin Notes Margin notes in the text point out additional facts, further emphasize
points, or point to related discussion either earlier or later in the book. Margin Notes
are denoted with an ~ icon that is also placed in the narrative and links the margin
note with the relevant passage in the text.

\ New in This Edition

There are several important changes in this fourth edition of the textbook. As we have
done in each edition, we have replaced a number of the Insight sections to make them
more current and to try to include topics that will appeal to a wider range of student
interests. Thus, we have introduced three new topics for the chapter-opening insights:
Critical Materials in Chapter l, Natura l Gas Production in Chapter 5, and Urban
Air Pollution in Chapter 11. We have also reworked the Polymer insight theme for
Chapter 2 to focus more specifically on the emerging area of conducting polymers.
The closing insight sections for Chapters 1 and 11 have also been rewritten, and the
closing section of Chapter 13 has been updated to highlight topics with more current
relevance.
In this revision, we have also focused on the following areas:
• In the end-of-chapter problems for each chapter, we have added an additional
section labeled as Conceptual Problems. These sections emphasize molecular level
visualization and nonalgorithmic problem solving, in an effort to help foster con-
ceptual understanding that goes beyond manipulating equations.
• In Chapter 1, we introduce the idea of systems thinking, and this concept is revis-
ited throughout the text.
• \rVe have revised a number of figures throughout in an effort to make them more
useful to students.
• Wherever possible, references to date-specific information have been updated.
• We have updated all periodic tables to include the recently approved names for
heavy elements and all atomic weight listings to use the IUPAC 2015 values.
Beyond these changes running throughout the book, a detailed list of specific changes
in each chapter is given below.

Preface xxi
 Chapter Summary of Changes

i\1ajor Change
• Changed the opening Insight and chapter theme to focus on the concept
of critical materials
• Includes new opening Insight section
Includes changes in se"eral example problems
• Includes changes at several points in the text ''here references to
context are made
Includes changes for several Figures (1.1, 1.2, 1.6, I. I0, I. I I, 1.12)
Includes changes to end-of-chapter problems related to the context theme
Other Changes
• Introduced the importance of systems and systems thinking, ''h1ch is then
used where appropriate in later chapters
• Changed closing Insight theme to touchscreen technology
2 Major Change
• Changed the opening Insight from the pre,;ous focu~ on polymers to a
more directed focus on new conducting polymers
• Includes changes in the opening Insight section
• includes changes in several example problems
Includes changes at se,·eral points in the text where references to con-
text are made

3 • Added a simple introduction to the Bronsted-Lowry definition of acids and

bases, which is also now addressed in more detail in Chapter 12
• Added an important note related to the proposed change in the IUP \ C
definition of the mole, which is likely to take place during the life of this
edition

4 • Tightened description of how mole ratios can be defined using the bal-
anced chemical equation
• Replaced Example Problem +.7 with an updated version
5 Major Change
• Changed the opening Insight and chapter theme to natural gas production
• Includes new opening Insight discussing hydraulic fracturing and other
aspects of natural gas recO\·ery and refining
Includes changes in se,·eraJ example problems
Includes changes at several points in the text where references to con-
text are made
• Includes new Figure 5.1
• Includes changes to end-of-chapter problems related to the context
theme

6 • Moved treatment of anion and cation sizes from C hapter 7 into this chap-
ter to group this concept with trends in atomic sizes
• Improved artwork for several figures, particularly those related to atomic
orbitals

7 • Moved material on ionic size and trends in ionic sizes out of this chapter
and into Chapter 6
• Revised artwork for several figures, particularly those related to orbita ls
8 • Revised amrnrk for several figures
• Added a brief discussion of dipole ,·ectors and molecular polarity in the
discussion of intermoleular forces

9 • Incorporated a discussion of systems thinking within the broader context

of the world energy economy
• Updated all data and figures containing dated infom1ation on the energy
economy

10 • Incorporated a di cussion of systems thinking in terms of resources and

use and disposal of consumer products

xxii Preface
 Chapter Summary of Changes

Jl 'vlajor Change
• Changed the opening Insight and chapter theme to urban air pollution and
the role of kinetics in smog formation
Includes new opening Insight
Includes changes in several example problems
• Includes changes at several points in the text where references to con-
text are made
Includes changes for Figures l l.l, 11.2, and 11.3
Includes changes to end-of-chapter problems related to the context
theme
Includes a new closing Insight on air quality monitoring

12 Major Change
• Added extensive discussion of acid-base chemistry and equilibrium, includ-
mg titrations and titration curves

13 • U pdated closing Insight section to include discussion of more recent

failures of lithium-ion batteries in consumer products

14 Improved consistency of notation used to refer to specific isotopes, espe-

cially in end-of-chapter problems

\ Supporting Material
Please visit WW\\.cengage.com/chemistry/ brownholme/chemengineer-te for more
information about student and instructor resources for this text.

\ Acknowledgments
We are very excited to see this book move forward in this fourth editio n, an d we
are grateful for the help and support we have e njoyed from a large and talented
team of pro fessionals. There are many people without whom we never could have
done this. But foremost among them are our fami lies, to whom this book is again
dedicated.
The origin of this text can be traced back many years, and as we move into this
new edition, we would like once more to thank a few people who were instrumental
in getting this project started.Jennifer Laugier first brought the two of us together to
work on a book for engineering students. J ay Campbell's work as developmental edi-
tor for the first edition was tremendous, and without his efforts the book may never
have been published. \i\Then Jay became involved, the project had been languishing
for some time, and the subsequent gains in momentum were clearly not coincidental.
The editorial leadership team at that time, consisting of MichelleJulet, David Har-
ris, and Lisa Lockwood, was also crucial in seeing this project come to fruition . The
decision to launch a book in a market segm ent that had not really existed was clearly
not an easy one, and we appreciate the confidence that everyone at what was then
Brooks/Cole placed in us.
In the development of the fourth edition, our Cengage team includes a mix of
the familiar and the new. \Ve would like to thank our product manager, Lisa Lock-
wood, whose continued support is always appreciated. Our Content Developer
for this edition is P eter McGahey, and both Lisa and Peter contributed g reatly to
discussions on where to focus our efforts in this revision. Peter has worked with us
through the entire revision process and provided a number of suggestions that have

Preface xxiii
 improved the finished edition. Stacey Lutkoski and Lynn Lustberg at \lPS Lim· tc: d
have overseen the production process. Photo and text resea rch \\as handl ed b' n
team at Lumina Datamatics. Anne Alexander (~1 ilwaukec chool of Engineeri ng)
and Dan Collins (Texas A&M University) helped us check the page proofs, pron d-
ing valuable comments that have improved the accuracy of the text. The book in
your hands truly reflects the best efforts of many hard-working professionals, and
we are grateful to all of them for their roles in this project.
It has been 12 years since the first edition was published, and throughout th.n
time, we have received useful feedback from numerous students and colleagues. Mud
of that feedback is informal, including e-mail from students or faculty members poin
ing out errors they ha,•e found or letting us know about sections they really like
Although there is no way to list all of the people who have contributed in this way, \\C
do sincerely thank you all.
Faculty members from a wide va riety of institutions also provided more formal
comments on the text at various stages of its de\'elopment. \Ve thank the following
re,;ewers for their contributions to the current re\ision.
Nuwan De Silva, Fmmingham State Unh•ersity
Donovan Dixon, University of Cemrnl Florida
E lizabeth Griffith, University ofMnrylmul
Roy Sagar, / ew Jersey Institute ofTec/1110/ogy
Kimberly Schunncier, Georgia Institute ofTeclmolo?J'
Thomas Sorensen, University of Wisco11si11-iV/ilwnukee
Todd Wind man, Arizona State University
\Ve also thank the following reviewers for their contributions to the development of
the earlier editions of the book.
D arrel Axtell, Saint Mnnin's University
Simon Bolt, University ofHouston
Patricia Muisener, University ofSouth Florida
Diana Phillips, Kettering University
Paul A. DiMilla, onhenstem University
Walter England, University ofWisconsin-Milwnukee
~1ary Hadley, Minnesota State University, 1Wa11kato
Andy J orgensen , University ofToledo
Karen Knaus, University of Colorado-Denver
Pamela Wolff, Cadeton University
Grigori y Yablonsky, Sni11t Louis University
Robert Angelici, !own State University
Allen Apblett, Oklahoma State University
J effrey R. Appling, Clemson University
Rosemary Bartoszek-Loza, The Ohio State University
Danny Bedgood, Charles Sturt University
J am es D. Carr, University of Nebraska
Victoria Castells, University ofMiami
Paul Charlesworth, Michigan Technologiml University
Richard Chung, San Jose State University
C harles Cornett, University of Wisco11si11-Platteville
Robert Cozzens, George Alason University

xxiv Preface
Ronald Evilia, University of New Orleans
John Falconer, University of Colomdo
Sandra Greer, University ofMaryland
Benjamin S. Hsaio, State University of New York at Stony Brook
Gerald Korenowski, Rensselaer Polytechnic Institute
Yin fa \fa, University ofMissouri-Rolla
Gerald Ray Miller, University oflvlaryland
Linda \1ona, Montgomery College
Michael Mueller, Rose-Hu/man Institute ofTeclmolog;y
Kristen \forphy, University of Wisconsin-Milwaukee
Thomas]. Murphy, University ofMmyland
Richard N afshun, Oregon State University
Scott Oliver, State University ofNew York at Binghamton
The late Robert Paine, Rochester Institute ofTeclmology
Steve Rathbone, Blinn College
Jesse Reinstein, University of Wisconsin-Platteville
Don Sw, Arizona State University
Mike Sha\\, Southem Illinois University-Edwardsville
J oycc Solochek, 1ifilwaukee School ofE11ginee1·ing
J ack Tossell, University ofMaryland
Peter T \,folczanski, Coniell University

LARRY BROWN
TOM HOLME
JUNE 201 7

Preface xxv
 Student Introduction

\ Chemistry and Engineering

As you begin this chemistry course, odds arc that you ma} be \\Ondering "\Vhy do I
have to take chemistry anyway? I'll never really need to knO\\ any of this to be an cngi
neer." o we'd like to begin by offering just a few examples of the many links between
our chosen field of chemistry and the various branches of engineering. The most ob-
\'ious examples, of course, might come from chemical engineering. :\1any chemical
engineers are involved with the design or optimization of processes in the chemical
industry, so it is clear that they would be dealing with concepts from chemistry on a
daily basis. Similarly, civil or environmental engineer working on em1ronmental pro-
tection or remediation might spend a lot of time thinking about chemical reactions
taking place in the water supply or the air. But\\ hat about other engineering fields?
.Much of modern electrical engineering relies on solid-state de\1ces whose proper-
ties can be tailored by carefully controlling their chemical compositions. And although
most electrical engineers do not regularly make their own chips, an understanding of
how those chips operate on an atomic scale is certainly helpful. As the push for ever
smaller circuit components continues, the ties between chemistry and electrical en-
gineering will grow tighter. From organic light-emitting diodes (OLEDs) to single
molecule transistors, new developments will continue to move out of the chemistry lab
and into working devices at an impressive pace.
Some applications of chemistry in engineering are much less obvious. At 1483 feet,
the Petronas Towers in Kuala Lumpur, Malaysia, were the tallest buildings in the
world when they were completed in 1998. Steel was in short supply in Malaysia, so
the towers' architects decided to build the structures out of something the country had
an abundance of and local engineers were familiar with: concrete. But the impressive
height of the towers required exceptionally strong concrete. The engineers eventually
settled on a material tl1at has come to be known as high-strength concrete, in which
chemical reactions between silica fume and Portland cement produce a stronger mate-
ria l, more resistant to compression. This example illustrates the relevance of chemistry
even to very traditional fields of engineering, and we will discuss some aspects of the
chemistry of concrete in Chapter 12, including the development of novel bendable
concrete.

\ About This Text

Both of us have taught general chemistry for many years, and we are familiar with the
difficulties that students may encounter with the subject. Perhaps more importantly,
for the past several years, we've each been teaching engineering students in the type
of one-semester course for which this text is designed. The approach to subjects pre-
sented in this text draws from both levels of experience.
\Ve've worked hard to make this text a readable and student friendly as possible.
One feature that makes this book different from any other text you could have used for
this course is that we incorporate connections between chemistry and engineering as a
fundamental component of each chapter. You will notice that each chapter begins and

xxvi
 ends with a section called an IUH@:ll . These sections are only the beginning of the
connections, and the theme introduced in the initial insight appears regularly through-
out that chapter. This special icon identifies material that is closely related to the theme
of the chapter opening Insight section. We've heard many students complain that they
don't see \\hat chemistry has to do with their chosen fields, and we hope that this ap-
proach might help you to see some of the connections.
Engineering students tend to take a fairly standard set of courses during their first
year of college, so it's likely that you might be taking calculus and physics courses along
with chemistry. We've tried to point out places where strong connections between
these subjecc; exist, and at the same time to do this in a way that does not disadvantage
a student who might be taking a precalculus math class. Thus we may refer to simi-
larities between equations you see here and those you might find in a physics text, but
we do not presume that you are already familiar with those equations. In the case of
math, we use special sections called MathConnections to discuss the use of math, and Math Connections
especially calculus, in chemistry. If you are familiar with calculus or are taking it con-
currently with this class, these sections will help you to see how some of the equations
used in chemistry emerge from calculus. But if you are not yet taking calculus, you can
simply skip over these sections and still be able to work with the needed equations.
Although our primary intent is to help you learn chemistry, we also believe
that this text an d the course for which you are using it ca n help you to develop a
broad set of skills that you will use throughout your studies and your career. Fore-
most among them is problem solving. Much of the work done by practicing engi-
neers can be characterized as solving problems. The problems you will confront in
your chemistry class clearly will be diffe rent from those yo u will see in e ngineer-
ing, physics, or math. But taken together, all of these subjects will help you formu-
late a consistent approach that can be used to attack virtually any problem. Many
of our students tend to "jump right in" and start writing equations when facing a
problem. But it is usually a better idea to think about a plan of attack before doing
that, especially if the problem is difficult or unfamiliar. Thus all of our worked ex-
amples include a Strateg;y section in which we outline the path to a solution before Strategy
starting to calculate anything. The Solution section then puts that strategy into ac- Solution
tion. For most numerical examples, we follow the solution with a section we call Analyze Your Answer
Analyze l1mr Anrom; in which we use estimation or comparison to known values to
Discussion
confirm that our result makes sense. We've seen many students who believe that
Check Your Understanding
whatever their calcul ator shows must be the right answer, even when it should be
easy to see that a mistake has been made. Many examples also include a Disws-
sion section in which we might talk about common pitfalls that you should avoid
or how the problem we've just done relates to other ideas we've a lready explored.
Finally, each example problem closes with a Check Your Understanding question or
problem, which gives you a chance to practice the skills illustrated in the example
or to extend them slightly. Answers to these Check Your Understanding questions ap-
pear in Appendix J.
While we are thinking abou t the exa mple problems, a few words about rounding
and significant figures are in order. In solving the example problems, we have used
atomic weights with the full number of significant figures shown in the periodic table
inside the back cover. \ Ve have also used as many significant figures as available for
constants such as the speed of light or the universal gas constant. \ Vhere intermedi-
ate results are shown in the text, we have tried to write them with the appropriate
number of significant figures. But when those same intermediate results are used in a
subsequent calculation, we have not rounded the values. Instead, we retain the full cal-
culator result. Only the final answer has actually been rounded. If you follow this same
procedure, you should be able to duplicate our answers. (fhe same process has been
used to generate the answers to numerical problems appearing in Appendix K.) For
problems that involve finding the slope or intercept of a line, the values shown have
been obtained by linear regression using the algorithms built into either a spreadsheet
or a graphing calculator.

Student Introduction xxvii

 Focus On Problem Solving A unique feature of this text is the inclusion of a Focus 011 Problem Solving questmn
at the end of each chapter. These questions are designed to force you to think about the
process of solving the problem rather than just getting an anS\ver. ln many cases, thes
problems do not include sufficient information to allow you to reach a final solutior.
Although we knO\\ from experience that many beginning engineering srudencs m1 ,rht
find this frustrating, we feel it is a good approximation to the kind of problems that a
working engineer might confront. Seldom would a client sit down and provide e\ el)
piece of information that you need to solve the problem at hand.
One of the most common questions we hear from students is" I low should I study
for chemistry?" Sadly, that question is most often asked after the student has done
poorly on one or more exams. Because different people learn best in different wa} S
there isn't a single magic formu la to ensure that everyone does well in chemistry. But
there are some common strategies and practices that we can recommend. First and
foremost, we suggest that you avoid getting behind in any of your classes. Leaming
takes time, and very few people can master three chapters of chemistry (or physics, or
math, or engineering) the night before a big exam. Getting behind in one class ine\ i-
tably leads to letting things slide in others, so you should strive to keep up from the
oucset. Most professors urge students to read the relevant textbook material before
it is presented in class. \Ve agree that this is the best approach becau e even a general
familiarity with the ideas being presented will help you to get a lot more out of your
class time.
In studying for exams, you should try to make a realistic a se sment of what you
do and don't understand. AJthough it can be discomforting to focus on the problems
that you don't seem to be able to get right, spending more time studying things that
you have already mastered will probably have less impact on your grade. Engineering
students tend to focus much of their attention on numerical problems. Although such
calculations are likely to be very important in your chemistry class, we also encourage
you to try to master the chemica l concepts behind them. Odds are that your professor
will test you on qua litative or conceptual material, too.
Finally, we note that this textbook is information rich. It includes many of the top-
ics that normally appear in a full year college chemistry course, but it is designed for
a course that takes only one semester. To manage the task of paring down the volume
of materials, we've left out some topics and shortened the discussion of others. Having
the Internet available means that you can always find more information if what you
have read sparks your interest.
\i\'e are excited that this book has made it into your hands. We hope you enjoy your
semester of learning chemistry and that this book is a positive part of you r experience.

LARRY BROWN
TOM HOLME
JUNE 2017

xxviii Student lntrodud1on