Quantitative Chemical Analysis

828 Pages·2006·10.08 MB·English

by  Daniel C. Harris

Quantitative Chemical Analysis
[“The Experiment”by Sempe ©C.Charillon, Paris.]
Quantitative Chemical
Analysis
SEVENTH EDITION
Daniel C. Harris
Michelson Laboratory
China Lake, California
W. H. Freeman and Company
New York
Publisher: Craig Bleyer
Senior Acquisitions Editor: Jessica Fiorillo
Marketing Manager:Anthony Palmiotto
Media Editor: Victoria Anderson
Associate Editor: Amy Thorne
Photo Editors: Cecilia Varas/Donna Ranieri
Design Manager: Diana Blume
Cover Designer: Trina Donini
Text Designer: Rae Grant
Text Layout: Jerry Wilke
Senior Project Editor: Mary Louise Byrd
Illustrations: Fine Line Illustrations
Illustration Coordinators: Shawn Churchman/Susan Timmins
Production Coordinator: Paul W. Rohloff
Composition: TechBooks/GTS Companies, York, PA
Printing and Binding: RR Donnelley
Library of Congress Control Number: 2006922923
ISBN: 0-7167-7041-5
EAN: 9780716770411
© 2007 by W. H. Freeman and Company
Printed in the United States of America
First printing
Brief Contents
0 The Analytical Process 1 17 Electroanalytical Techniques 348
1 Measurements 9 18 Fundamentals
of Spectrophotometry 378
2 Tools of the Trade 20
19 Applications
3 Experimental Error 39
of Spectrophotometry 402
4 Statistics 53
20 Spectrophotometers 424
5 Quality Assurance and 21 Atomic Spectroscopy 453
Calibration Methods 78
22 Mass Spectrometry 474
6 Chemical Equilibrium 96
23 Introduction to Analytical
7 Let the Titrations Begin 121 Separations 501
8 Activity and the Systematic 24 Gas Chromatography 528
Treatment of Equilibrium 140
25 High-Performance Liquid
9 Monoprotic Acid-Base Chromatography 556
Equilibria 158
26 Chromatographic Methods
10 Polyprotic Acid-Base and Capillary Electrophoresis 588
Equilibria 180
27 Gravimetric and Combustion
11 Acid-Base Titrations 199 Analysis 628
12 EDTA Titrations 228 28 Sample Preparation 644
13 Advanced Topics in
Notes and References NR1
Equilibrium 250
Glossary GL1
14 Fundamentals
Appendixes AP1
of Electrochemistry 270
Solutions to Exercises S1
15 Electrodes and Potentiometry 298
Answers to Problems AN1
16 Redox Titrations 327 Index I1
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Contents
Preface xiii 4-2 Confidence Intervals 57
4-3 Comparison of Means with Student’s t 59
0 The Analytical Process 1 Box 4-1 Analytical Chemistry and the Law 63
4-4 Comparison of Standard Deviations
A Biosensor for Arsenic in the Environment
with the FTest 63
0-1 The Analytical Chemist’s Job 2
4-5 tTests with a Spreadsheet 64
0-2 General Steps in a Chemical Analysis 7
4-6 QTest for Bad Data 65
Box 0-1 Constructing a Representative Sample 7
4-7 The Method of Least Squares 65
4-8 Calibration Curves 69
1 Measurements 9
Box 4-2 Using a Nonlinear Calibration Curve 71
4-9 A Spreadsheet for Least Squares 71
Ultrasensitive Measurement of Atoms
in a Vapor
1-1 SI Units 9 5 Quality Assurance and
1-2 Chemical Concentrations 12 Calibration Methods 78
1-3 Preparing Solutions 14
The Need for Quality Assurance
1-4 Stoichiometry Calculations 16
5-1 Basics of Quality Assurance 79
Box 5-1 Control Charts 81
2 Tools of the Trade 20
5-2 Method Validation 82
The Smallest Balances Box 5-2 The Horwitz Trumpet: Variation
2-1 Safe, Ethical Handling of Chemicals and Waste 20 in Interlaboratory Precision 85
Box 2-1 Disposal of Chemical Waste 21 5-3 Standard Addition 87
2-2 The Lab Notebook 22 5-4 Internal Standards 90
2-3 Analytical Balance 22
2-4 Burets 25 6 Chemical Equilibrium 96
2-5 Volumetric Flasks 26
Chemical Equilibrium in the Environment
2-6 Pipets and Syringes 27
6-1 The Equilibrium Constant 97
2-7 Filtration 29
6-2 Equilibrium and Thermodynamics 98
2-8 Drying 30
6-3 Solubility Product 100
2-9 Calibration of Volumetric Glassware 31
Box 6-1 Solubility Is Governed by More
2-10 Introduction to Microsoft Excel 33
Than the Solubility Product 101
2-11 Graphing with Microsoft Excel 35
Demonstration 6-1 Common Ion Effect 102
6-4 Complex Formation 102
3 Experimental Error 39
Box 6-2 Notation for Formation Constants 104
Experimental Error 6-5 Protic Acids and Bases 105
3-1 Significant Figures 39 6-6 pH 107
3-2 Significant Figures in Arithmetic 40 6-7 Strengths of Acids and Bases 108
3-3 Types of Error 42 Demonstration 6-2 The HCl Fountain 109
Box 3-1 Standard Reference Materials 43 Box 6-3 The Strange Behavior
3-4 Propagation of Uncertainty from Random Error 44 of Hydrofluoric Acid 110
Box 3-2 Propagation of Uncertainty Box 6-4 Carbonic Acid 113
in the Product x (cid:1) x 48 6-8 Solving Equilibrium Problems with a
3-5 Propagation of Uncertainty: Systematic Error 49 Concentration Table and a Spreadsheet 114
4 Statistics 53 7 Let the Titrations Begin 121
Is My Red Blood Cell Count High Today? Evolution of the Buret
4-1 Gaussian Distribution 53 7-1 Titrations 121
vii
Box 7-1 Reagent Chemicals and 10-4 Which Is the Principal Species? 190
Primary Standards 123 10-5 Fractional Composition Equations 191
7-2 Titration Calculations 123 10-6 Isoelectric and Isoionic pH 193
7-3 Spectrophotometric Titrations 126 Box 10-2 Isoelectric Focusing 194
7-4 The Precipitation Titration Curve 127
7-5 Titration of a Mixture 131 11 Acid-Base Titrations 199
7-6 Calculating Titration Curves with
Acid-Base Titration of a Protein
a Spreadsheet 132
11-1 Titration of Strong Base with Strong Acid 200
7-7 End-Point Detection 133
11-2 Titration of Weak Acid with Strong Base 202
Demonstration 7-1 Fajans Titration 134
11-3 Titration of Weak Base with Strong Acid 205
7-8 Efficiency in Experimental Design 134
11-4 Titrations in Diprotic Systems 206
8 Activity and the Systematic 11-5 Finding the End Point with a pH Electrode 208
Box 11-1 Alkalinity and Acidity 209
Treatment of Equilibrium 140
11-6 Finding the End Point with Indicators 212
Hydrated Ions Demonstration 11-1 Indicators and
8-1 The Effect of Ionic Strength on the Acidity of CO 214
2
Solubility of Salts 141 Box 11-2 What Does a Negative pH Mean? 214
Demonstration 8-1 Effect of Ionic Box 11-3 World Record Small Titration 216
Strength on Ion Dissociation 141 11-7 Practical Notes 216
Box 8-1 Salts with Ions of Charge (cid:2)|2| 11-8 The Leveling Effect 216
Do Not Fully Dissociate 143 11-9 Calculating Titration Curves with Spreadsheets 218
8-2 Activity Coefficients 143
8-3 pH Revisited 147 12 EDTA Titrations 228
8-4 Systematic Treatment of Equilibrium 147
Ion Channels in Cell Membranes
Box 8-2 Calcium Carbonate Mass
12-1 Metal-Chelate Complexes 229
Balance in Rivers 150
12-2 EDTA 231
8-5 Applying the Systematic Treatment
Box 12-1 Chelation Therapy and Thalassemia 232
of Equilibrium 150
12-3 EDTA Titration Curves 235
9 Monoprotic Acid-Base Equilibria 158 12-4 Do It with a Spreadsheet 237
12-5 Auxiliary Complexing Agents 238
Measuring pH Inside Cellular Box 12-2 Metal Ion Hydrolysis Decreases
Compartments the Effective Formation Constant
9-1 Strong Acids and Bases 159 for EDTA Complexes 240
Box 9-1 Concentrated HNO Is Only 12-6 Metal Ion Indicators 241
3
Slightly Dissociated 159 Demonstration 12-1 Metal Ion Indicator
9-2 Weak Acids and Bases 161 Color Changes 241
9-3 Weak-Acid Equilibria 162 12-7 EDTA Titration Techniques 244
Box 9-2 Dyeing Fabrics and the Fraction Box 12-3 Water Hardness 245
of Dissociation 164
Demonstration 9-1 Conductivity 13 Advanced Topics in Equilibrium 250
of Weak Electrolytes 165
Acid Rain
9-4 Weak-Base Equilibria 166
13-1 General Approach to Acid-Base Systems 251
9-5 Buffers 167
13-2 Activity Coefficients 254
Box 9-3 Strong Plus Weak Reacts Completely 170
13-3 Dependence of Solubility on pH 257
Demonstration 9-2 How Buffers Work 171
13-4 Analyzing Acid-Base Titrations with
10 Polyprotic Acid-Base Equilibria 180 Difference Plots 263
Proteins Are Polyprotic Acids and Bases 14 Fundamentals
10-1 Diprotic Acids and Bases 181
of Electrochemistry 270
Box 10-1 Successive Approximations 186
10-2 Diprotic Buffers 187 Electricity from the Ocean Floor
10-3 Polyprotic Acids and Bases 188 14-1 Basic Concepts 270
viii Contents
Box 14-1 Molecular Wire 273 17-2 Electrogravimetric Analysis 353
14-2 Galvanic Cells 274 17-3 Coulometry 355
Demonstration 14-1 The Human Salt Bridge 277 17-4 Amperometry 357
14-3 Standard Potentials 277 Box 17-l Oxygen Sensors 358
14-4 Nernst Equation 279 Box 17-2 What Is an “Electronic Nose”? 360
Box 14-2 E° and the Cell Voltage Do Not 17-5 Voltammetry 362
Depend on How You Write the Cell Reaction 280 Box 17-3 The Electric Double Layer 365
Box 14-3 Latimer Diagrams: How to 17-6 Karl Fischer Titration of H O 370
2
Find E° for a New Half-Reaction 282 Demonstration 17-2 The Karl Fischer
14-5 E° and the Equilibrium Constant 283 Jacks of a pH Meter 371
Box 14-4 Concentrations in the
18 Fundamentals of
Operating Cell 284
Spectrophotometry 378
14-6 Cells as Chemical Probes 285
14-7 Biochemists Use E°(cid:3) 288
The Ozone Hole
15 Electrodes and Potentiometry 298 18-1 Properties of Light 379
18-2 Absorption of Light 380
A Heparin Sensor Box 18-1 Why Is There a Logarithmic
15-1 Reference Electrodes 299 Relation Between Transmittance and
15-2 Indicator Electrodes 301 Concentration? 382
Demonstration 15-1 Potentiometry 18-3 Measuring Absorbance 383
with an Oscillating Reaction 302 Demonstration 18-1 Absorption Spectra 383
15-3 What Is a Junction Potential? 303 18-4 Beer’s Law in Chemical Analysis 385
15-4 How Ion-Selective Electrodes Work 303 18-5 What Happens When a Molecule
15-5 pH Measurement with a Glass Electrode 306 Absorbs Light? 387
Box 15-1 Systematic Error in Rainwater Box 18-2 Fluorescence All Around Us 391
pH Measurement: The Effect of 18-6 Luminescence 392
Junction Potential 310 Box 18-3 Instability of the Earth’s Climate 395
15-6 Ion-Selective Electrodes 311
19 Applications
15-7 Using Ion-Selective Electrodes 317
15-8 Solid-State Chemical Sensors 318 of Spectrophotometry 402
16 Redox Titrations 327 Fluorescence Resonance Energy
Transfer Biosensor
Chemical Analysis of High-Temperature 19-1 Analysis of a Mixture 402
Superconductors 19-2 Measuring an Equilibrium Constant:
16-1 The Shape of a Redox Titration Curve 328 The Scatchard Plot 407
Demonstration 16-1 Potentiometric 19-3 The Method of Continuous Variation 408
Titration of Fe2(cid:4) with MnO– 332 19-4 Flow Injection Analysis 410
4
16-2 Finding the End Point 332 19-5 Immunoassays and Aptamers 411
16-3 Adjustment of Analyte Oxidation State 335 19-6 Sensors Based on Luminescence Quenching 414
16-4 Oxidation with Potassium Permanganate 336 Box 19-1 Converting Light into Electricity 414
16-5 Oxidation with Ce4(cid:4) 337
20 Spectrophotometers 424
Box 16-1 Environmental Carbon
Analysis and Oxygen Demand 338
Cavity Ring-Down Spectroscopy:
16-6 Oxidation with Potassium Dichromate 339
Do You Have an Ulcer?
16-7 Methods Involving Iodine 340
20-1 Lamps and Lasers: Sources of Light 426
Box 16-2 Iodometric Analysis of High-
Box 20-1 Blackbody Radiation and the
Temperature Superconductors 342
Greenhouse Effect 426
17 Electroanalytical Techniques 348 20-2 Monochromators 429
20-3 Detectors 433
How Sweet It Is! Box 20-2 The Most Important Photoreceptor 435
17-1 Fundamentals of Electrolysis 349 20-4 Optical Sensors 437
Demonstration 17-1 Electrochemical 20-5 Fourier Transform Infrared Spectroscopy 442
Writing 350 20-6 Dealing with Noise 448
Contents ix