Preview Chemistry The Central Science, 3rd Edition by Theodore L. Brown, H. Eugene LeMay, Bruce E. Bursten, Catherine Murphy, Patrick Woodward, Steven Langford, Dalius Sagatys, Adrian Georg (2013)

Preview Chemistry The Central Science, 3rd Edition by Theodore L. Brown, H. Eugene LeMay, Bruce E. Bursten, Catherine Murphy, Patrick Woodward, Steven Langford, Dalius Sagatys, Adrian Georg (2013) Preview Chemistry The Central Science, 3rd Edition by Theodore L. Brown, H. Eugene LeMay, Bruce E. Bursten, Catherine Murphy, Patrick Woodward, Steven Langford, Dalius Sagatys, Adrian Georg (2013) Preview Chemistry The Central Science, 3rd Edition by Theodore L. Brown, H. Eugene LeMay, Bruce E. Bursten, Catherine Murphy, Patrick Woodward, Steven Langford, Dalius Sagatys, Adrian Georg (2013) Preview Chemistry The Central Science, 3rd Edition by Theodore L. Brown, H. Eugene LeMay, Bruce E. Bursten, Catherine Murphy, Patrick Woodward, Steven Langford, Dalius Sagatys, Adrian Georg (2013)

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Copyright © Pearson Australia (a division of Pearson Australia Group Pty Ltd) 2014 – 9781442554603 – Brown/Chemistry: The central science 3e

3 R D E D I T I O N

CHEMISTRY

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whose enthusiasm and curiosity have inspired us to undertake this project

Copyright © Pearson Australia (a division of Pearson Australia Group Pty Ltd) 2014

Authorised adaptation from the United States edition entitled Chemistry: The Central Science, 12th edition,

ISBN 01321696727 by Brown, Theodore L.; LeMay, H Eugene Jr; Bursten, Bruce E.; Murphy, Catherine J.;

Woodward, Patrick M., published by Pearson Education, Inc., copyright © 2012.

Third adaptation edition published by Pearson Australia Group Pty Ltd, Copyright © 2014.

The Copyright Act 1968 of Australia allows a maximum of one chapter or 10% of this book, whichever is the

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ISBN: 9781442559462 (Vital Source)

1 Introduction: Matter and Measurement 2

3 Stoichiometry: Calculations with Chemical Formulae and Equations 66

Preface xxii

chapter 1

Introduction: Matter and

The atomic and molecular perspective of

STRATEGIES IN CHEMISTRY The importance

of practice and estimating answers 21

STRATEGIES IN CHEMISTRY The features of

Atomic numbers, mass numbers and

detailed contents

detailed contents vii

MY WORLD OF CHEMISTRY Elements

Names and formulae of binary molecular

Chapter summary and key terms 58

chapter 3

Stoichiometry: Calculations with

chemical formulae and equations 66

Indicating the states of reactants and products 70

Combination and decomposition reactions 71

STRATEGIES IN CHEMISTRY Problem solving 76

MY WORLD OF CHEMISTRY Glucose

Interconverting masses and numbers of

Molecular formulae from empirical formulae 85

Reactions in aqueous solutions 102

Solubility guidelines for ionic compounds 108

Neutralisation reactions with gas formation 116

Oxidation of metals by acids and salts 120

Expressing the concentration of an electrolyte 126Interconverting molarity, moles and volume 127

viii Chemistry: the central science

MY WORLD OF CHEMISTRY Drinking too

Nuclear chemistry: Changes within

MY WORLD OF CHEMISTRY Medical

applications of radiotracers 160

A CLOSER LOOK The dawning of the

Electronic structure of atoms 178

Hot objects and the quantisation of energy 183

The energy states of the hydrogen atom 187

MY WORLD OF CHEMISTRY Australian

A CLOSER LOOK Probability density and radial

detailed contents ix

Electron spin and the Pauli exclusion

Chapter summary and key terms 212

chapter 7

Periodic properties of the elements 220

A CLOSER LOOK Effective nuclear charge 225

Variations in successive ionisation energies 231

Periodic trends in first ionisation energies 232

Electron configurations of ions of the

Differentiating ionic and covalent bonding 265

A CLOSER LOOK Oxidation numbers, formal charges and actual partial charges 272

Less than an octet of valence electrons 275More than an octet of valence electrons 276

Bond enthalpies and the enthalpies of

x Chemistry: the central science

MY WORLD OF CHEMISTRY Explosives and

Chapter summary and key terms 284

The effect of non-bonding electrons and

Molecules with expanded valence shells 301

Molecular orbitals from 2p atomic orbitals 319

Electron configurations for B2 to Ne2 321

A CLOSER LOOK Phases in atomic and

Electron configurations and molecular

Chapter summary and key terms 328

10.2 Pressure and its measurement 338

MY WORLD OF CHEMISTRY Blood pressure 340

The pressure–volume relationship: Boyle’s law 341The temperature–volume relationship:

The quantity–volume relationship:

Relating the ideal-gas equation and the

10.5 Further applications of the ideal-gas

Volumes of gases in chemical reactions 350

10.6 Gas mixtures and partial pressures 351

Application of kinetic-molecular theory to the

10.8 Molecular effusion and diffusion 358

MY WORLD OF CHEMISTRY Gas separations 362

10.9 Real gases: Deviations from ideal

detailed contents xi

Chapter summary and key terms 367

11.1 A molecular comparison of gases,

Volatility, vapour pressure and temperature 396

A CLOSER LOOK The Clausius–Clapeyron

The phase diagrams of H2O and CO2 399

MY WORLD OF CHEMISTRY Liquid crystal

The crystal structure of sodium chloride 407

Solution formation, spontaneity and disorder 430Solution formation and chemical reactions 431

12.2 Saturated solutions and solubility 432

12.3 Factors affecting solubility 434

12.4 Ways of expressing concentration 440

xii Chemistry: the central science

A CLOSER LOOK Ideal solutions with two or

Chapter summary and key terms 460

Photochemical reactions in the atmosphere 471

13.2 Human activities and Earth’s atmosphere 475

Nitrogen oxides and photochemical smog 479

Greenhouse gases: Water vapour, carbon

MY WORLD OF CHEMISTRY Methane as a

13.4 Human activities and Earth’s water 485

Water purification: Municipal treatment 487

14.2 The first law of thermodynamics 505

detailed contents xiii

14.9 Entropy and the second law of

A CLOSER LOOK The entropy change when a

14.10 Molecular interpretation of entropy 535

Expansion of a gas at the molecular level 535

Making qualitative predictions about S 538

14.11 Entropy changes in chemical reactions 542

14.12 Gibbs free energy (Gibbs energy) 545

14.13 Gibbs energy and temperature 548

MY WORLD OF CHEMISTRY Driving

A CLOSER LOOK Using spectroscopic

methods to measure reaction rates 573

Reaction orders: Exponents in the rate law 573

Using initial rates to determine rate laws 576

15.4 The change of concentration with time

The rate-determining step for a multistep

MY WORLD OF CHEMISTRY The Haber

xiv Chemistry: the central science

Equilibrium constants in terms of pressure,

16.3 Interpreting and working with

The magnitude of equilibrium constants 623

The direction of the chemical equation

Relating chemical equation stoichiometry

16.5 Calculating equilibrium constants 629

16.6 Applications of equilibrium constants 631

Calculating equilibrium concentrations 633

16.7 The equilibrium constant and free

Change in reactant or product concentration 638

Effects of volume and pressure changes 641

A CLOSER LOOK Controlling nitric oxide

17.1 Acids and bases: A brief review 656

17.2 Brønsted–Lowry acids and bases 656

Relative strengths of acids and bases 660

17.8 Relationship between Ka and Kb 683

MY WORLD OF CHEMISTRY Amines and

17.9 Acid–base properties of salt solutions 685

An anion’s ability to react with water 686

A cation’s ability to react with water 686Combined effect of cation and anion in

Chapter summary and key terms 697

Composition and action of buffer solutions 711

Addition of strong acids or bases to buffers 715

MY WORLD OF CHEMISTRY Blood as a

MY WORLD OF CHEMISTRY Tooth decay

18.6 Precipitation and separation of ions 738

18.7 Qualitative analysis for metallic elements 740

Chapter summary and key terms 743

19.5 Free energy and redox reactions 772

Emf, free energy and the equilibrium constant 774

19.6 Cell potentials under non-standard

xvi Chemistry: the central science

Chapter summary and key terms 792

chapter 20

Chemistry of the non-metals 802

20.1 Periodic trends and chemical

Properties and preparation of the halogens 813

20.6 The other group 16 elements: S, Se, Te

MY WORLD OF CHEMISTRY Nitrogen fixation

MY WORLD OF CHEMISTRY Nitroglycerin and

20.10 The other group 14 elements: Si, Ge,

detailed contents xvii

The development of coordination chemistry:

Charges, coordination numbers and

21.3 Ligands with more than one donor

21.4 Nomenclature and isomerism in

MY WORLD OF CHEMISTRY The battle for

Electron configurations in octahedral

Tetrahedral and square planar complexes 880

Chapter summary and key terms 883

MY WORLD OF CHEMISTRY Structure–activity

Free-radical reactions and electron movement 913

A CLOSER LOOK Reactivity by carbon

xviii Chemistry: the central science

chapter 23

Stereochemistry of organic

23.1 Stereochemistry in organic chemistry 928

23.2 Cis–trans isomerism in cycloalkanes 929

23.3 Chirality in organic compounds 931

Using priority rules to find a stereocentre’s

23.6 Molecules with more than one

Chapter summary and key terms 944

chapter 24

Chemistry of alkenes and alkynes 952

24.1 The structure of unsaturated

24.3 Arrow notation and resonance

MY WORLD OF CHEMISTRY The chemistry of

24.4 Electrophilic addition reactions 966

Addition reactions involving HX (X = Cl, Br, I) 967

Halogenation: Addition of Br2 and Cl2 972

Chapter summary and key terms 987

chapter 25

Alcohols, haloalkanes and ethers 994

25.1 Alcohols: Structure, properties and

detailed contents xix

25.6 Haloalkanes to alkenes: -elimination 1015

25.7 Substitution versus elimination 1018

A CLOSER LOOK Nucleophile or Lewis base? 1019

26.2 Preparation of aldehydes and ketones 1039

26.3 Reactions of aldehydes and ketones 1042

Addition of carbon nucleophiles—Grignard

Addition of nitrogen and oxygen nucleophiles:

Halogenation of aldehydes and ketones 1053

MY WORLD OF CHEMISTRY Glucosamine 1058

Oligosaccharides and polysaccharides 1060

MY WORLD OF CHEMISTRY Cyclodextrins 1062

Chapter summary and key terms 1067

27.2 Preparation of carboxylic acids 1084

27.5 Acid chlorides, anhydrides and

27.6 Condensation polymerisation 1100

MY WORLD OF CHEMISTRY Towards the

MY WORLD OF CHEMISTRY Biodegradable

xx Chemistry: the central science

Chapter summary and key terms 1107

chapter 28

Benzene and its derivatives 1114

28.4 Acidity of alcohols and phenols 1124

28.5 Electrophilic aromatic substitution

Directing groups and substitution effects 1129

Chapter summary and key terms 1138

29.3 Proteins, peptides and enzymes 1172

MY WORLD OF CHEMISTRY B group

Chapter summary and key terms 1189

chapter 30

Solving molecular structure 1198

30.1 The electromagnetic spectrum 1200

A CLOSER LOOK Using spectroscopic methods to measure reaction rates 1202

MY WORLD OF CHEMISTRY IR spectroscopy for biological imaging 1209

30.3 Nuclear magnetic resonance (NMR)

Nuclear magnetic resonance frequencies 1212

MY WORLD OF CHEMISTRY Nuclear spin and magnetic resonance imaging 1213

detailed contents xxi

Electron impact ionisation mass spectrometry 1226

30.5 Compound identification using spectra 1232

Deducing the molecular formula of an organic

E Standard reduction potentials at 25 °C 1264

Answers to Concept Checks 1265 Answers to Figure it Out 1274

Philosophy

This is the third Australian edition of a text that has enjoyed significant global success over a number

of decades Our original aim in adapting Chemistry: The Central Science for a wider market was

to ensure that the text remained a central, indispensable learning tool for the student of chemistry

In this book we aim to provide a comprehensive coverage of all aspects of chemistry that may

be used at introductory university level It will provide students with the depth of knowledge they

require in their first-year undergraduate curriculum and to arm chemistry academics across

Austra-lia with a broad and balanced view of chemistry with which to set their curricula Throughout the

text we have maintained a conversational style of explaining information rather than simply stating

facts We have found that this style has been highly appreciated by the student

Organisation and Contents

In this edition the first four chapters give a largely macroscopic overview of chemistry The basic

concepts presented—such as atomic structure, the nature of chemical reactions, stoichiometry,

measurement and quantification and the main types of reaction in aqueous solution—provide a

necessary background for many of the laboratory experiments usually performed in first year general

chemistry

The following five chapters (Chapters 5–9) focus on the atomic scale, starting with the transformations

that occur within the nucleus of an atom before moving on to deal with the electronic structure of the

atom, the consequent effects on the properties of the elements and the basic theories of chemical

bonding and molecular geometry Chapters 10 and 11 consider the macroscopic properties of

the three states of matter—gas, liquid and solid—and the forces which influence their behaviour A

more detailed look at solubility and solutions and our interaction with the atmosphere and oceans

are examined in the next two chapters (Chapters 12 and 13) All chemical reactions involve energy

changes and Chapter 14 comprehensively covers the thermodynamic processes operating in all

chemical reactions

The next several chapters examine the factors that determine the speed and extent of chemical

reactions: kinetics (Chapter 15) and equilibria (Chapters 16–18) These are followed by

electro-chemistry, which discusses the use of chemical reactions to produce electrical energy and vice

versa (Chapter 19) Chapters 20 and 21 introduce the chemistry of non-metals, metals and

coordination compounds Throughout Chapters 1–21 there are extensive areas of modern chemistry

that are dealt with broadly For example, we introduce students to descriptive inorganic chemistry

by integrating examples throughout the text You will find pertinent and relevant examples of organic

and inorganic chemistry woven into all chapters as a means of illustrating principles and

applica-tions and the relaapplica-tionship between all areas of chemistry Some chapters, of course, more directly

address the properties of elements and their compounds, especially Chapters 7, 20 and 21

Organic chemistry is central to all living things and Chapters 22–30 lead us on a journey from

elementary hydrocarbons to elaborate bioorganic molecules Much of what we discuss is treated

Preface xxiii

from a fundamental level so your transition to tertiary studies in organic chemistry is smooth and

rapid We place emphasis on the core reactions observed in organic chemistry and treated many

cases mechanistically This fosters a deep understanding of why organic molecules react in the way

they do thereby giving you an opportunity to understand much more chemistry than is discussed

Chapter 22 provides a foundation to our examination of organic chemistry by using hydrocarbons

to illustrate how we represent and name organic molecules It goes on to provide an overview of

the functional groups—the reactive parts of the molecule—on which we build our understanding

of organic chemistry The shape of a molecule may be pivotal in determining its reactivity, particularly

in a biological context, and Chapter 23 leads to an in-depth discussion of stereochemistry

The next six chapters cover the fundamental reactions encountered in organic chemistry, at each

step building to the application of these reaction in a modern world (for example, polymerisation in

Chapters 24 and 27) and their essential role in the chemistry of life (for example, carbohydrates in

Chapter 26, fats in Chapter 27, proteins and nucleic acids in Chapter 29) Chapter 28 investigates

aromatic compounds as a separate class Here it is important for the student to note the differences

in reactivity to the alkenes studied in Chapter 24

Finally, Chapter 30 stands alone as a reference guide to mass spectrometry, NMR spectroscopy

and IR spectroscopy Whether these topics are taught with much emphasis on the technology is up

to the instructor What we believe is most important is students’ development at complex

problem-solving, bringing two or more concepts together to draw a logical conclusion The approach to solving

molecular structure also confirms their knowledge of the basic principles of organic chemistry, bonding,

functional groups and drawing structural formulae Our coverage of organic chemistry gives students a

unique perspective and challenges the very ‘standard format’ often seen in a first-year text

Our topic sequence provides a logical progression through chemistry, but we recognise that not

everyone teaches all the topics in exactly the order we have chosen We have therefore made

sure that instructors can make common changes in teaching sequence with no loss in student

comprehension In particular, many instructors prefer to introduce gases (Chapter 10) after

stoichiometry or after thermochemistry rather than with states of matter The chapter on gases has

been written to permit this change with no disruption in the flow of material It is also possible to treat

the balancing of redox equations (Sections 19.1 and 19.2) earlier, after the introduction of redox

reactions in Section 4.4 Finally, some instructors like to cover organic chemistry (Chapters 22 to

30) earlier than its position in this text Throughout the text we have introduced linkages (indicated

by the symbol •) to sections in other parts of the book This allows the reader to quickly find

relevant material and highlights the integrated nature of chemistry A glossary of terms provides

succinct definitions for quick reference and a comprehensive index ensures the extensive information

contained in this book is easily accessible

Monash University, Clayton VIC 3800steven.langford@sci.monash.edu.au

Queensland University of Technology, Brisbane QLD 4001d.sagatys@qut.edu.au

University of Sydney, NSW 2006adrian.george@sydney.edu.au

guided tour for students

MAKING CONNECTIONS

The 3rd edition of Chemistry: The Central Science includes several

key features to help you see the bigger picture: to move beyond memorisation and have a deeper understanding of the relationships between concepts in chemistry

Making connections across different topics

New enhanced blue links • are featured in the margins and include voice balloons which direct you to other relevant sections that will enrich your understanding of the current topic

Making connections between chemistry and the real world

My World of Chemistry

Chemistry occurs all around us, throughout every day Recognising the importance of chemistry in your daily life can improve your understanding

of chemical concepts My World of Chemistry showcases chemistry’s

connection to world events, scientific discoveries, and medical breakthroughs throughout the text

Making connections visually

Micro to Macro Art

These illustrations offer three parts: a macroscopic image (what you can see with your eyes); a molecular image (what the molecules are doing); and a symbolic representation (how chemists represent the process with symbols and equations)

A new intermediate step has been added, showing where chemistry occurs in the problem-solving process

*NEW* Figure It Out questions and Voice Balloons

Figure It Out questions encourage you to stop and analyse the artwork

in the text, for conceptual understanding ‘Voice Balloons’ in selected figures help you break down and understand the components of the image

GLUCOSE MONITORING

Over 1 million Australians (although estimates vary) have diabetes, and globally the number ap- proaches 172 million Diabetes is a metabolic disorder in which the body either cannot pro- duce or cannot properly use the hormone insulin One signal that a person is diabetic

is that the concentration of glucose in the blood is higher than

normal Therefore, people who are diabetic need to measure

their blood glucose concentrations regularly Untreated

dia-betes can cause severe complications such as blindness and

loss of limbs.

The body converts most of the food we eat into glucose.

After digestion, glucose is delivered to cells via the blood.

Cells need glucose to live, and insulin must be present in order

for glucose to enter the cells Normally, the body adjusts the

concentration of insulin automatically, in concert with the

Glucose meters work by the introduction of blood from a person, usually by a prick of the finger, onto a small strip of paper that contains chemicals that react with glucose Inser- tion of the strip into a small battery-operated reader gives the glucose concentration The mechanism of the readout varies from one monitor to another—it may be a measurement of a small electrical current or measurement of light produced in a chemical reaction Depending on the reading on any given day, a diabetic person may need to receive an injection of insulin or simply stop eating sweets for a while.

H

H

H

+  DT LVUHGXFHG JDLQVHOHFWURQV + 

C 2 O 4(aq)

F I G U R E I T O U T

Which species is reduced in this reaction? Which species is the reducing agent?

« FIGURE 19.2 Titration of an acidic solution of Na2C2O4 with KMnO4(aq).

Project2_Layout 1 4/03/13 2:31 PM Page 1

• Review this on page xx

Project2_Layout 1 4/06/13 2:26 PM Page 1

guided tour for students xxv

Making connections to problem-solving and critical thinking skills

Analyse/Plan/Solve/Check

This four-step problem-solving method helps you understand what you are being asked to solve, to plan how you will solve each problem, to work your way through the solution, and to check your answers This method is introduced in Chapter 3 and reinforced throughout the book

Dual-Column Problem-Solving Strategies

Found in Selected Sample Exercises, these strategies explain the thought process involved in each step of a mathematical calculation using a unique layout for clarity They help you develop a conceptual understanding of those calculations

Strategies in Chemistry

Strategies in Chemistry teach ways to analyse information and organise thoughts, helping to improve your problem-solving and critical-thinking abilities

126 CHAPTER 4 Reactions in Aqueous Solution

SAMPLE EXERCISE 4.10 Calculating molar concentrations of ions

solution of calcium nitrate?

SOLUTION Analyse We are given the concentration of the ionic compound used to make the so-

lution and asked to determine the concentrations of the ions in the solution.

Plan We can use the subscripts in the chemical formula of the compound to

deter-mine the relative ion concentrations.

SAMPLE EXERCISE 4.9 Calculating molarity

SOLUTION

Analyse We are given the number of grams of solute

the solution.

Plan We can calculate molarity using Equation 4.33 To do so,

we must convert the grams of solute to moles and the volume

of the solution from millilitres to litres.

PRACTICE EXERCISE

Answer:0.278 M

(See slso Exercises 4.45, 4.46.)

Expressing the Concentration of an Electrolyte

When an ionic compound dissolves the relative concentrations of the ions introduced into the solution depend on the chemical formula of the compound.

For example, a 1.0 M solution of NaCl is 1.0 M in Na + ions and 1.0 M in Cl - ions.

Similarly, a 1.0 M solution of Na 2 SO 4 is 2.0 M in Na + ions and 1.0 M in SO 4 - ions.

Thus, the concentration of an electrolyte solution can be specified either in terms of the compound used to make the solution (1.0 M Na 2 SO 4 ) or in terms of the ions that the solution contains (2.0 M Na + and 1.0 M SO 4 - ).

*Brown 3e - ch04 (India).QXD_BLB02_038-075hr2 5/03/13 10:20 AM Page 126

PRACTICE EXERCISE

Answers:(a) 78.0 u, (b) 32.0 u

(See also Exercises 3.17, 3.18.)

Percentage Composition from Formulae

Occasionally we must calculate the percentage composition of a compound (that

is, the percentage by mass contributed by each element in the substance) For example, in order to verify the purity of a compound, we may wish to compare the calculated percentage composition of the substance with that found experi- mentally Calculating percentage composition is a straightforward matter if the chemical formula is known

76 CHAPTER 3 Stoichiometry: Calculations with Chemical Formulae and Equations

explic-as atomic mexplic-asses) Recognise also that your plan may involve either a single step or a series of steps with intermediate answers.

suitable equations or relationships to solve for the unknown.

Be careful with significant figures, signs and units.

sure you have found all the solutions asked for in the problem.

Does your answer make sense? That is, is the answer geously large or small or is it in the ballpark? Finally, are the units and significant figures correct?

outra-PROBLEM SOLVING

Practice is the key to success in solving problems.

As you practise, you can improve your skills by following these steps.

problem carefully What is it asking you to do? What information does it provide you with? List both the data you are given and the quantity you need to obtain (the unknown).

possible path between the given information and the unknown.

This is usually a formula, an equation or some principle you

STRATEGIES IN CHEMISTRY

parenthe-ses, the subscript outside the theses is a multiplier for all atoms

164.1 u

SAMPLE EXERCISE 3.6 Calculating percentage composition

SOLUTION Analyse We are given a chemical formula which shows the elements and the num-

ber of atoms of each element in the molecule.

Plan We see that Equation 3.10 relates % composition of an element in a molecule to

the number of atoms of each element, the atomic mass of each element and the mula mass of the molecule The formula mass can be calculated as in Exercise 3.5 and the atomic masses can be obtained from the periodic table

for-Solve Using Equation 3.10 and the periodic table to obtain atomic masses, we have

*Brown 3e - ch03 (India).QXD_BLB03_038-075 5/03/13 10:25 AM Page 76

you read that 1 mol of nitrogen is produced in a particular reaction You might

interpret this statement to mean 1 mol of nitrogen atoms (14.0 g) Unless

other-wise stated, however, what is probably meant is 1 mol of nitrogen molecules,

N 2 (28.0 g), because N 2 is the usual chemical form of the element To avoid

ambiguity, it is important to state explicitly the chemical form being discussed.

Using the chemical formula N2avoids ambiguity.

SAMPLE EXERCISE 3.9 Calculating molar mass

SOLUTION

Analyse We are given a molecular formula which gives us the types of atoms and

their number in the molecule.

Plan The molar mass of any substance is numerically equal to its formula mass

proceed as in Sample Exercise 3.5.

Solve Our first step is to determine the formula mass of glucose.

Because glucose has a formula mass of 180.0 u, one mole of this substance has a mass

appropri-ate unit for the molar mass.

Comment Glucose is sometimes called dextrose Also known as blood sugar,

glu-cose is found widely in nature, occurring, for example, in honey and fruits Other

types of sugars used as food are converted into glucose in the stomach or liver before

they are used by the body as energy sources Because glucose requires no conversion,

it is often given intravenously to patients who need immediate nourishment

million Australians (although estimates

diabetes, and globally the number

ap-hes 172 million Diabetes is a metabolic

rder in which the body either cannot

pro-ce or cannot properly use the hormone

sulin One signal that a person is

diabet-tration of glucose in the blood is higher

efore, people who are diabetic need to

d glucose concentrations regularly

cause severe complications such as

blind-bs.

most of the food we eat into glucose.

is delivered to cells via the blood.

to live, and insulin must be present in

enter the cells Normally, the body adjusts

insulin automatically, in concert with the

eaten for 8 hours or more is diagnosed as diabetic if his or her

Glucose meters work by the introduction of blood from a person, usually by a prick of the finger, onto a small strip of paper that contains chemicals that react with glucose Inser- tion of the strip into a small battery-operated reader gives the glucose concentration The mechanism of the readout varies from one monitor to another—it may be a measurement of a small electrical current or measurement of light produced in a chemical reaction Depending on the reading on any given day, a diabetic person may need to receive an injection of insulin or simply stop eating sweets for a while.

Reading Quizzes: The Item Library in

MasteringChemistry includes Reading

Quizzes that educators can assign to

ensure students have completed their

readings and are prepared for class

discussion and activities

Gradebook: MasteringChemistry is the only

system to capture the step-by-step work of

each student in class, including wrong answers

submitted, hints requested, and time taken on

every step This data powers an unprecedented

gradebook

Mastering Chemistry

for Chemistry: The Central Science, 3rd Edition

A Guided Tour for Students and Educators

Personalised coaching and feedback:

MasteringChemistry is the only system to provide instantaneous feedback specific to the most common wrong answers Students can submit an answer and receive immediate error-specific feedback Simpler sub-problems—hints—are provided upon request

Online and tablet eText: The eText gives students and educators access to the text whenever and wherever they can access the internet The eText pages look exactly like the printed text and include powerful interactive and customisation features

Students and educators can:

• create notes (educators can share these with a whole class)

• highlight text in different colours

• create book marks

• click hyperlinked words and phrases to view definitions

• view in single-page or two-page format

• perform a full-text search and save or export notes

guided tour for educators

Learning and Teaching Tools

Instructors Solution Manual

Organised by chapter, this manual offers detailed lecture outlines and complete descriptions of all

available lecture demonstrations, the interactive media assets, common student misconceptions,

and more It also offers solutions to all end-of-chapter exercises in the textbook

Computerised TestBank

The test bank allows educators to customise the bank of questions to meet specific needs

and add/revise questions as needed It consists of more than 2000 true–false, multiple choice,

short-answer, essay and matching questions complete with solutions Using Pearson’s TestGen

software, lecturers can create professional-looking exams in just minutes by building tests from the

existing database of questions, editing questions, or adding your own TestGen also supports the

creation of printed, network or online testsk

Digital Image Library

The digital image library provides all images and artwork from the book

TECHNICAL EDITORS

Dr Simon Bedford, University of Wollongong

Chris Fellows, University of New England

EDITORIAL REVIEW BOARD

Dr Simon Bedford, University of Wollongong

Penny Commons, University of Melbourne

Professor Bice Martincigh, University of

KwaZulu-NatalProfessor Joe Shapter, Flinders University

Dr David Wilson, La Trobe University

Dr Greg Doran, Charles Sturt University

Dr Damian Laird, Murdoch University

Dr Gwendolyn Laurie, The University of Queensland

Professor Joe Shapter, Flinders UniversityAssociate Professor Kieran F Lim, Deakin University

Dr Evan Robertson, La Trobe University

Dr Andrew J Seen, University of Tasmania

Ms Rosemary Ward, University of Technology, Sydney

Dr Magdalena Wajrak, Edith Cowan University

Dr Danny K Y Wong, Macquarie University

We would also like to express our gratitude to our many team members at Pearson Australia whose

hard work, imagination, and commitment have contributed so greatly to the final form of this edition:

Mandy Sheppard, our Chemistry Editor, for many fresh ideas and her unflagging enthusiasm,

continuous encouragement, and support; Catherine du Peloux Menage, our Development Editor,

who very effectively coordinated the scheduling and tracked the multidimensional deadlines that

come with a project of this magnitude; Michael Stone, Manager—Product Development, whose

diligence and careful attention to detail were invaluable to this revision, especially in keeping us

on task in terms of consistency and student understanding; Katie Millar, our Senior Project Editor,

who managed the complex responsibilities of bringing the design, photos, artwork, and writing

together with efficiency and good cheer; and Lisa Woodland, our Copyright & Pictures Editor, who

researched and secured rights for stunning photographs to bring the concepts to life

Finally, to Theodore Brown, Eugene LeMay, Bruce Bursten, Catherine Murphy and Patrick

Woodward we thank you sincerely for allowing us to use your textbook as the foundation to

a broad perspective

STEVEN J LANGFORD received his BSc (Hons I) and PhD from The University of Sydney After postdoctoral work in the UK under the auspices of a Ramsay Memorial Fellowship, and at the University

of UNSW as an ARC Postdoctoral Fellow, he joined the School of Chemistry at Monash University in 1998 He was appointed Profes-sor of Organic Chemistry in 2006 and is currently Deputy Dean and Associate Dean (Research) of the Faculty of Science He teaches all aspects of organic and supramolecular chemistry in Monash’s undergraduate program and is known for his entertaining and enthusiastic teaching style In 2005 Professor Langford was awarded the inaugural Faculty of Science Dean’s Excellence in Science Teaching Award and in 2006 was

one of only a handful of scientists to receive a Carrick Citation For Outstanding Contributions to

Student Learning in Australian university teaching He was also awarded the Centenary of Federation

teaching award from the Royal Australian Chemical Institute—its premier teaching award—in that

same year His research interests focus on concept transfers from nature, particularly in the areas

of photosynthesis and genetic encoding He has published over 100 research articles and was

awarded the 2006 Young Investigator Award by the Society of Porphyrins and Phthalocyanines

DALIUS S SAGATYS received his BSc(Hons) degree in Chemistry from The University of Queensland (Brisbane) and his PhD from the Illinois Institute of Technology (Chicago) in 1970 After three years

as Joliot Curie Fellow of the Commissariat á L’Energie Atomique, Université de Paris VII (Paris), he worked at the International Patents Institute in Rijswijk, Holland, and from there returned to Brisbane where

he joined the then Queensland Institute of Technology in 1982 From the beginning he became interested in the design and implementation

of chemistry courses for very different student requirements, such as those in the fields of nursing, engineering and the built environment,

as well as developing a chemistry bridging course for students with no chemistry background at all

His research interests have been centred on the synthesis and structure determination of complexes

of the Group 15 elements, specifically arsenic, antimony and bismuth He is currently a Visiting

Academic at Queensland University of Technology

about the australian authors xxxi

ADRIAN V GEORGE received his BSc(Hons) and PhD degrees from

The University of Reading in England and joined the staff there as a

lecturer in 1984 After a short spell as a guest scientist at The University

of California, Berkeley he moved to The University of Sydney in 1988

His research has ranged from organic synthesis at extremely high

pressures and the development of new organometallic materials to

the use of isotope ratio mass spectrometry in the detection of doping

in competitive sports and chemistry education He has conducted

research in Japan and taught University level chemistry in Sweden

He has always had a passion for teaching and obtained a graduate

certificate of education in 2000 He has been awarded a University of Sydney Excellence in Teaching

award (1999), Vice Chancellor’s award for Support of the Student Experience twice (2007, 2011),

the inaugural Royal Australian Chemical Institute Centenary of Federation Teaching Award (2001),

Australian College of Education Teaching Award (2001) and was part of a team that received the

Carrick Institute Award for Programs that Enhance Learning (2007) He has been Director of First Year

Studies in the School of Chemistry and the Associate Dean (Teaching and Learning) in the Faculty

of Science at The University of Sydney He currently divides his time between academic pursuits at

The University of Sydney and rain forest regeneration in northern New South Wales

THEODORE L BROWN received his PhD from Michigan State University in 1956 Since then, he has been a member of the faculty of the University of Illinois, Urbana-Champaign, where he is now Professor of Chemistry, Emeritus He served as Vice Chancellor for Research, and Dean of The Graduate College, from 1980 to 1986, and as Founding Director of the Arnold and Mabel Beckman Institute for Advanced Science and Tech-nology from 1987 to 1993 Professor Brown has been an Alfred P Sloan Foundation Research Fellow and has been awarded a Guggenheim Fellowship In 1972 he was awarded the American Chemical Society Award for Research in Inorganic Chemistry and received the American Chemical Society Award for Distinguished Service in the Advancement of Inorganic Chemistry in 1993 He has been elected a Fellow of the American Association for the Advancement of Science, the American Academy of Arts and Sciences, and the American Chemical Society.

H EUGENE LEMAY, JR. received his BS degree in Chemistry from Pacific Lutheran University (Washington) and his PhD in Chemistry in 1966 from the University of Illinois, Urbana-Champaign.He then joined the faculty of the University of Nevada, Reno, where

he is currently Professor of Chemistry, Emeritus He has enjoyed Visiting Professorships at The University of North Carolina at Chapel Hill, at The University College of Wales in Great Britain, and at The University of California, Los Angeles Professor LeMay is a popular and effective teacher, who has taught thousands of students during more than 40 years of university teaching Known for the clarity of his lectures and his sense of humour, he has received several teaching awards, including the University Distinguished Teacher of the Year Award (1991) and the first Regents’ Teaching Award given by the State of Nevada Board of Regents (1997)

BRUCE E BURSTEN received his PhD in Chemistry from the University of Wisconsin in

1978 After two years as a National Science Foundation Postdoctoral Fellow at Texas A&M University, he joined the faculty of The Ohio State University, where he rose to the rank

of Distinguished University Professor In 2005, he moved to The University of Tennessee, Knoxville, as Distinguished Professor of Chemistry and Dean of the College of Arts and Sciences Professor Bursten has been a Camille and Henry Dreyfus Foundation Teacher-Scholar and an Alfred P Sloan Foundation Research Fellow, and he is a Fellow of both the American Association for the Advancement of Science and the American Chemical Society At Ohio State he has received the University Distinguished Teaching Award in

1982 and 1996, the Arts and Sciences Student Council Outstanding Teaching Award

about the american authors xxxiii

in 1984, and the University Distinguished Scholar Award in 1990 He received the Spiers Memorial

Prize and Medal of the Royal Society of Chemistry in 2003, and the Morley Medal of the Cleveland

Section of the American Chemical Society in 2005 He was President of the American Chemical

Society for 2008 In addition to his teaching and service activities, Professor Bursten’s research

program focuses on compounds of the transition-metal and actinide elements

CATHERINE J MURPHY received two BS degrees, one in Chemistry and one in

Biochemistry, from The University of Illinois, Urbana-Champaign, in 1986 She received her

PhD in Chemistry from The University of Wisconsin in 1990 She was a National Science

Foundation and National Institutes of Health Postdoctoral Fellow at the California Institute

of Technology from 1990 to 1993 In 1993, she joined the faculty of The University of

South Carolina, Columbia, becoming the Guy F Lipscomb Professor of Chemistry in 2003

In 2009 she moved to The University of Illinois, Urbana-Champaign, as the Peter C and

Gretchen Miller Markunas Professor of Chemistry Professor Murphy has been honoured

for both research and teaching as a Camille Dreyfus Teacher-Scholar, an Alfred P Sloan

Foundation Research Fellow, a Cottrell Scholar of the Research Corporation, a National

Science Foundation CAREER Award winner, and a subsequent NSF Award for Special Creativity She

has also received a USC Mortar Board Excellence in Teaching Award, the USC Golden Key Faculty

Award for Creative Integration of Research and Undergraduate Teaching, the USC Michael J Mungo

Undergraduate Teaching Award, and the USC Outstanding Undergraduate Research Mentor Award

Since 2006, Professor Murphy has served as a Senior Editor for the Journal of Physical Chemistry

In 2008 she was elected a Fellow of the American Association for the Advancement of Science

Professor Murphy’s research program focuses on the synthesis and optical properties of inorganic

nanomaterials, and on the local structure and dynamics of the DNA double helix

PATRICK M WOODWARD received BS degrees in both Chemistry and Engineering from

Idaho State University in 1991 He received a MS degree in Materials Science and a PhD

in Chemistry from Oregon State University in 1996 He spent two years as a postdoctoral

researcher in the Department of Physics at Brookhaven National Laboratory In 1998, he

joined the faculty of the Chemistry Department at The Ohio State University where he

currently holds the rank of Professor He has enjoyed visiting professorships at the University

of Bordeaux in France and the University of Sydney in Australia Professor Woodward has

been an Alfred P Sloan Foundation Research Fellow and a National Science Foundation

CAREER Award winner He currently serves as an Associate Editor to the Journal of Solid

State Chemistry and as the director of the Ohio REEL program, an NSF-funded centre

that works to bring authentic research experiments into the laboratories of first- and second-year

chemistry classes in 15 colleges and universities across the state of Ohio Professor Woodward’s

research program focuses on understanding the links between bonding, structure, and properties of

solidstate inorganic functional materials

KEY CONCEPTS

1.1 THE STUDY OF CHEMISTRY

We begin with a brief description of what chemistry is and why it is useful to learn chemistry

1.2 CLASSIFICATIONS OF MATTER

We discuss some fundamental ways of classifying matter,

distinguishing between pure substances and mixtures and between elements and compounds.

1.3 PROPERTIES OF MATTER

We describe the different characteristics or properties of matter,

used to characterise, identify and separate substances.

We observe that all measured quantities have an inherent

uncertainty that is expressed by the number of significant figures

used to report the quantity Significant figures are also used to express the uncertainty associated with calculations involving measured quantities

The universe is full of mysteries that we will

probably never comprehend And even on Earth

some of the simple things that we see and

experience can be quite mysterious How do we obtain

electricity from a battery? How does a plant grow? How

does a modern LED television screen work? There

are innumerable questions, which while seemingly

unanswerable, can actually be answered by the study of

chemistry

the changes that matter undergoes

This first chapter lays a foundation for our studies byproviding an overview of what chemistry is about and whatchemists do The preceding Key Concepts list indicates thechapter organisation and some of the ideas that we willconsider

1.1 THE STUDY OF CHEMISTRY

The Atomic and Molecular Perspective of Chemistry

Chemistry involves studying the properties and behaviour of matter Matteris

the physical material of the universe: it is anything that has mass and occupies

space A property is any characteristic that allows us to recognise a particulartype of matter and to distinguish it from other types This book, your body, theclothes you are wearing, the water you drink and the air you are breathing areall examples of matter It has long been known that all matter is composed ofinfinitesimally small building blocks called atoms Despite the tremendousvariety of matter in the universe, there are only about 100 different types ofatoms that occur in nature and these, combined in various combinations andproportions, constitute all of the matter of the universe We will see that the

properties of matter relate not only to the kinds of atoms it contains tion), but also to the arrangements of these atoms (structure).

(composi-Atoms can combine to form moleculesin which two or more atoms arejoined in specific shapes Throughout this text you will see molecules repre-sented using coloured spheres to show how their component atoms connect toeach other (¥ FIGURE 1.1) The colour merely provides a convenient way to dis-tinguish between different kinds of atoms As examples, compare the molecules

of ethanol and ethylene glycol, depicted in Figure 1.1 Notice that these cules differ somewhat in composition Ethanol contains one red sphere, whichrepresents one oxygen atom, whereas ethylene glycol contains two

Even apparently minor differences in the composition or structure of cules can cause profound differences in their properties Ethanol, also calledgrain alcohol, is the alcohol in beverages such as beer and wine Ethylene glycol,however, is a viscous liquid used as coolant in car radiators

mole-Every change in the observable world—from boiling water to the changesthat occur as our bodies combat invading viruses—has its basis in the world of

4 CHAPTER 1 Introduction: Matter and Measurement

Ethylene glycol Aspirin

models The white, black and red

spheres represent atoms of

hydrogen, carbon and oxygen,

respectively.

atoms and molecules Thus as we proceed with our study of chemistry, we will

find ourselves thinking in two realms: the macroscopic realm of ordinary-sized

objects (macro = large) and the submicroscopic realm of atoms and molecules We

make our observations in the macroscopic world—in the laboratory and in our

everyday surroundings In order to understand that world, however, we must

visualise how atoms and molecules behave at the submicroscopic level

Chem-istry is the science that seeks to understand the properties and behaviour of

matter by studying the properties and behaviour of atoms and molecules

C O N C E P T C H E C K 1

a. In round numbers, about how many elements are there?

b. What submicroscopic particles are the building blocks of matter?

Why Study Chemistry?

You will note, when studying any scientific discipline, whether it be biology,

engi-neering, medicine, agriculture, geology and so forth, that chemistry is an integral

part of your curriculum This is because chemistry, by its very nature, is the central

science, central to a fundamental understanding of other sciences and technologies.

Chemistry provides an important understanding of our world and how it works It

is an extremely practical science that greatly impacts on our daily living Indeed,

chemistry lies near the heart of many matters of public concern: improvement of

health care, conservation of natural resources, protection of the environment and

provision of our everyday needs for food, clothing and shelter

Using chemistry, we have discovered pharmaceutical chemicals that

enhance our health and prolong our lives We have increased food production

through the development of fertilisers and pesticides We have developed

plas-tics and other materials that are used in almost every facet of our lives

Unfortu-nately, some chemicals also have the potential to harm our health or the

environment It is in our best interests as educated citizens and consumers to

understand the profound effects, both positive and negative, that chemicals

have on our lives and to strike an informed balance about their uses

Let’s begin our study of chemistry by examining some fundamental ways in

which matter is classified and described Two principal ways of classifying

matter are according to its physical state (gas, liquid or solid) and according to

its composition (element, compound or mixture) as explained below

States of Matter

A sample of matter can be a gas, a liquid or a solid These three forms of matter

are called the states of matter The states of matter differ in some of their simple

observable properties A gas (also known as vapour) has no fixed volume or

shape; rather, it conforms to the volume and shape of its container A gas can be

compressed to occupy a smaller volume, or it can expand to occupy a larger one

A liquidhas a distinct volume independent of its container but has no specific

shape: it assumes the shape of the portion of the container that it occupies A

solidhas both a definite shape and a definite volume Neither liquids nor solids

can be compressed to any appreciable extent

The properties of the states can be understood on the molecular level

(¥ FIGURE 1.2) In a gas the molecules are far apart and are moving at high

speeds, colliding repeatedly with each other and with the walls of the container

In a liquid the molecules are packed more closely together, but still move

rapidly, allowing them to slide over each other; thus liquids pour easily In a

solid the molecules are held tightly together, usually in definite arrangements, so

SECTION 1.2 Classifications of Matter 5

the molecules can wiggle only slightly

in their otherwise fixed positions.Changes in temperature and/or pres-sure can lead to a conversion from onestate of matter to another, illustrated

by such familiar processes as icemelting or water evaporating

Composition of Matter

When we discuss matter in daily language we often use the word substance as in, ‘This is a peculiar sub-stance!’ In fact, the word substance isused in everyday language as a substi-tute for matter which may be one kind

of matter or a mixture of more thanone kind of matter In chemistry,however, the word substance means

matter of uniform composition throughout

a sample, as well as having distinct

properties To emphasise this, weusually use the term pure substance.However, even when we use the wordsubstance by itself, it is understood torefer to a pure form of matter Forexample, oxygen, water, table sugar(sucrose), table salt (sodium chloride)should be referred to as pure substances but more usually are referred to simply

as substances

All substances are either elements or compounds Elements cannot bedecomposed into simpler substances; they may be atoms, or molecules com-posed of only one kind of atom (¥ FIGURE 1.3(a), (b)) Compounds are sub-stances composed of two or more different elements, so they contain two ormore kinds of atoms (Figure 1.3(c)) Water, for example, is a compound com-posed of two elements, hydrogen and oxygen Figure 1.3(d) shows a mixture ofsubstances Mixturesare combinations of two or more substances in which each

6 CHAPTER 1 Introduction: Matter and Measurement

Á FIGURE 1.2 The three physical states

of water: water vapour, liquid water and

ice Here we see both the liquid and solid

states of water We cannot see water vapour.

What we see when we look at steam or

clouds is tiny droplets of liquid water

dispersed in the atmosphere The molecular

views show that the molecules in the solid are

arranged in a more orderly way than in the

liquid The molecules in the gas are much

further apart than those in the liquid or the

solid.

Solid

Ice

Liquid Water

Gas Water vapour

Only one kind of atom is in any element Compounds must have at

least two kinds of atoms

Á FIGURE 1.3 Molecular comparison of elements, compounds and mixtures.

F I G U R E I T O U T

How do the molecules of a compound differ from the molecules of an element?

substance retains its own chemical identity and which can be separated into the

individual pure substances by various means

Some of the more common elements are listed in ¥ TABLE 1.1, along with

the chemical abbreviations of their names—chemical symbols—used to denote

them All the known elements and their symbols are listed on the inside front

cover of this text The table in which the symbol for each element is enclosed in

a box is called the periodic table which is discussed later (• Section 2.5, ‘The

Periodic Table’)

The symbol for each element consists of one or two letters, with the first

letter capitalised These symbols are often derived from the English name for the

element, but sometimes they are derived from a foreign name (usually Latin)

instead (last column in Table 1.1) You will need to know these symbols and to

learn others as we encounter them in the text

The observation that the elemental composition of a pure compound is

always the same is known as thelaw of constant composition (or the law of

definite proportions) It was first put forth by the French chemist Joseph Louis

Proust (1754–1826) in about 1800 Although this law has been known for

200 years, the general belief persists among some people that a fundamental

dif-ference exists between compounds prepared in the laboratory and the

corre-sponding compounds found in nature This is not true: a pure compound has the

same composition and properties regardless of its source Both chemists and

nature must use the same elements and operate under the same natural laws to

form compounds

C O N C E P T C H E C K 2

Hydrogen, oxygen and water are all composed of molecules What is it about the

molecules of water that makes water a compound?

Most of the matter we encounter consists of mixtures of different substances

Each substance in a mixture retains its own chemical identity and hence its own

properties Whereas pure substances have fixed compositions, the compositions

of mixtures can vary A cup of sweetened coffee, for example, can contain either

a little sugar or a lot The substances making up a mixture (such as sugar and

water) are called components of the mixture.

Some mixtures do not have the same composition, properties and

appear-ance throughout Both rocks and wood, for example, vary in texture and

appearance through out any typical sample Such mixtures are heterogeneous

(» FIGURE 1.4(a)) Mixtures that are uniform throughout are homogeneous Air is

a homogeneous mixture of the gaseous substances nitrogen, oxygen and smaller

amounts of other substances The nitrogen in air has all the properties that pure

nitrogen does because both the pure substance and the mixture contain the same

nitrogen molecules Salt, sugar and many other substances dissolve in water to

form homogeneous mixtures (Figure 1.4(b)) Homogeneous mixtures are also

called solutions

SECTION 1.2 Classifications of Matter 7

TABLE 1.1 • Some common elements and their symbols

Carbon C Aluminium Al Copper Cu (from cuprum)

Fluorine F Bromine Br Iron Fe (from ferrum)

Hydrogen H Calcium Ca Lead Pb (from plumbum)

Iodine I Chlorine Cl Mercury Hg (from hydrargyrum)

Nitrogen N Helium He Potassium K (from kalium)

Oxygen O Lithium Li Silver Ag (from argentum)

Phosphorus P Magnesium Mg Sodium Na (from natrium)

Sulfur S Silicon Si Tin Sn (from stannum)

Á FIGURE 1.4 Mixtures (a) Many

common materials, including rocks, are heterogeneous This granite shows a heterogeneous mixture of silicon dioxide and other metal oxides (b) Homogeneous mixtures are called solutions Many substances, including the blue solid shown in this photo (copper sulfate), dissolve in water

Finally, to Theodore Brown, Eugene LeMay, Bruce Bursten, Catherine Murphy and Patrick

Woodward we thank you sincerely... know these symbols and to

learn others as we encounter them in the text

The observation that the elemental composition of a pure compound is

always the same is known as the< b>law... elected a Fellow of the American Association for the Advancement of Science, the American Academy of Arts and Sciences, and the American Chemical Society.

H EUGENE LEMAY, JR.