Modern Analytical Chemistry

Chapter1
Introduction 1
1A What is Analytical Chemistry? 2
1B The Analytical Perspective 5
1C Common Analytical Problems 8
1D Key Terms 9
1E Summary 9
1F Problems 9
1G Suggested Readings 10
1H References 10

 

Chapter2
Basic Tools of Analytical Chemistry 11
2A Numbers in Analytical Chemistry 12
2A.1 Fundamental Units of Measure 12
2A.2 Significant Figures 13
2B Units for Expressing Concentration 15
2B.1 Molarity and Formality 15
2B.2 Normality 16
2B.3 Molality 18
2B.4 Weight, Volume, and Weight-to-Volume
Ratios 18
2B.5 Converting Between Concentration Units 18
2B.6 p-Functions 19
2C Stoichiometric Calculations 20
2C.1 Conservation of Mass 22
2C.2 Conservation of Charge 22
2C.3 Conservation of Protons 22
2C.4 Conservation of Electron Pairs 23
2C.5 Conservation of Electrons 23
2C.6 Using Conservation Principles in
Stoichiometry Problems 23
2D Basic Equipment and Instrumentation 25
2D.1 Instrumentation for Measuring Mass 25
2D.2 Equipment for Measuring Volume 26
2D.3 Equipment for Drying Samples 29
2E Preparing Solutions 30
2E.1 Preparing Stock Solutions 30
2E.2 Preparing Solutions by Dilution 31
2F The Laboratory Notebook 32
2G Key Terms 32
2H Summary 33
2I Problems 33
2J Suggested Readings 34
2K References 34

 

Chapter3
The Language of Analytical Chemistry 35
3A Analysis, Determination, and Measurement 36
3B Techniques, Methods, Procedures, and
Protocols 36
3C Classifying Analytical Techniques 37
3D Selecting an Analytical Method 38
3D.1 Accuracy 38
3D.2 Precision 39
3D.3 Sensitivity 39
3D.4 Selectivity 40
3D.5 Robustness and Ruggedness 42
3D.6 Scale of Operation 42
3D.7 Equipment, Time, and Cost 44
3D.8 Making the Final Choice 44
3E Developing the Procedure 45
3E.1 Compensating for Interferences 45
3E.2 Calibration and Standardization 47
3E.3 Sampling 47
3E.4 Validation 47
3F Protocols 48
3G The Importance of Analytical Methodology 48
3H Key Terms 50
3I Summary 50
3J Problems 51
3K Suggested Readings 52
3L References 52

 

Chapter4
Evaluating Analytical Data 53
4A Characterizing Measurements and Results 54
4A.1 Measures of Central Tendency 54
4A.2 Measures of Spread 55
4B Characterizing Experimental Errors 57
4B.1 Accuracy 57
4B.2 Precision 62
4B.3 Error and Uncertainty 64
4C Propagation of Uncertainty 64
4C.1 A Few Symbols 65
4C.2 Uncertainty When Adding or Subtracting 65
4C.3 Uncertainty When Multiplying or
Dividing 66
4C.4 Uncertainty for Mixed Operations 66
4C.5 Uncertainty for Other Mathematical
Functions 67
4C.6 Is Calculating Uncertainty Actually Useful? 68
4D The Distribution of Measurements and
Results 70
4D.1 Populations and Samples 71
4D.2 Probability Distributions for Populations 71
4D.3 Confidence Intervals for Populations 75
4D.4 Probability Distributions for Samples 77
4D.5 Confidence Intervals for Samples 80
4D.6 A Cautionary Statement 81
4E Statistical Analysis of Data 82
4E.1 Significance Testing 82
4E.2 Constructing a Significance Test 83
4E.3 One-Tailed and Two-Tailed Significance
Tests 84
4E.4 Errors in Significance Testing 84
4F Statistical Methods for Normal Distributions 85
4F.1 Comparing

X to μ 85
4F.2 Comparing s2 to σ2 87
4F.3 Comparing Two Sample Variances 88
4F.4 Comparing Two Sample Means 88
4F.5 Outliers 93
4G Detection Limits 95
4H Key Terms 96
4I Summary 96
4J Suggested Experiments 97
4K Problems 98
4L Suggested Readings 102
4M References 102

 

Chapter 5.
Calibrations, Standardizations,
and Blank Corrections 104
5A Calibrating Signals 105
5B Standardizing Methods 106
5B.1 Reagents Used as Standards 106
5B.2 Single-Point versus Multiple-Point
Standardizations 108
5B.3 External Standards 109
5B.4 Standard Additions 110
5B.5 Internal Standards 115
5C Linear Regression and Calibration Curves 117
5C.1 Linear Regression of Straight-Line Calibration
Curves 118
5C.2 Unweighted Linear Regression with Errors
in y 119
5C.3 Weighted Linear Regression with Errors
in y 124
5C.4 Weighted Linear Regression with Errors
in Both x and y 127
5C.5 Curvilinear and Multivariate
Regression 127
5D Blank Corrections 128
5E Key Terms 130
5F Summary 130
5G Suggested Experiments 130
5H Problems 131
5I Suggested Readings 133
5J References 134

 

Chapter 6.
Equilibrium Chemistry 135
6A Reversible Reactions and Chemical
Equilibria 136
6B Thermodynamics and Equilibrium
Chemistry 136
6C Manipulating Equilibrium Constants 138
6D Equilibrium Constants for Chemical
Reactions 139
6D.1 Precipitation Reactions 139
6D.2 Acid–Base Reactions 140
6D.3 Complexation Reactions 144
6D.4 Oxidation–Reduction Reactions 145
6E Le Châtelier’s Principle 148
6F Ladder Diagrams 150
6F.1 Ladder Diagrams for Acid–Base Equilibria 150
6F.2 Ladder Diagrams for Complexation
Equilibria 153
6F.3 Ladder Diagrams for Oxidation–Reduction
Equilibria 155
6G Solving Equilibrium Problems 156
6G.1 A Simple Problem: Solubility of Pb(IO3)2 in
Water 156
6G.2 A More Complex Problem: The Common Ion
Effect 157
6G.3 Systematic Approach to Solving Equilibrium
Problems 159
6G.4 pH of a Monoprotic Weak Acid 160
6G.5 pH of a Polyprotic Acid or Base 163
6G.6 Effect of Complexation on Solubility 165
6H Buffer Solutions 167
6H.1 Systematic Solution to Buffer
Problems 168
6H.2 Representing Buffer Solutions with
Ladder Diagrams 170
6I Activity Effects 171
6J Two Final Thoughts About Equilibrium
Chemistry 175
6K Key Terms 175
6L Summary 175
6M Suggested Experiments 176
6N Problems 176
6O Suggested Readings 178
6P References 178

 

Chapter 7.
Obtaining and Preparing Samples
for Analysis 179
7A The Importance of Sampling 180
7B Designing a Sampling Plan 182
7B.1 Where to Sample the Target
Population 182
7B.2 What Type of Sample to Collect 185
7B.3 How Much Sample to Collect 187
7B.4 How Many Samples to Collect 191
7B.5 Minimizing the Overall Variance 192
7C Implementing the Sampling Plan 193
7C.1 Solutions 193
7C.2 Gases 195
7C.3 Solids 196
7D Separating the Analyte from
Interferents 201
7E General Theory of Separation
Efficiency 202
7F Classifying Separation Techniques 205
7F.1 Separations Based on Size 205
7F.2 Separations Based on Mass or Density 206
7F.3 Separations Based on Complexation
Reactions (Masking) 207
7F.4 Separations Based on a Change
of State 209
7F.5 Separations Based on a Partitioning Between
Phases 211
7G Liquid–Liquid Extractions 215
7G.1 Partition Coefficients and Distribution
Ratios 216
7G.2 Liquid–Liquid Extraction with No Secondary
Reactions 216
7G.3 Liquid–Liquid Extractions Involving
Acid–Base Equilibria 219
7G.4 Liquid–Liquid Extractions Involving Metal
Chelators 221
7H Separation versus Preconcentration 223
7I Key Terms 224
7J Summary 224
7K Suggested Experiments 225
7L Problems 226
7M Suggested Readings 230
7N References 231

 

Chapter 8.
Gravimetric Methods of Analysis 232
8A Overview of Gravimetry 233
8A.1 Using Mass as a Signal 233
8A.2 Types of Gravimetric Methods 234
8A.3 Conservation of Mass 234
8A.4 Why Gravimetry Is Important 235
8B Precipitation Gravimetry 235
8B.1 Theory and Practice 235
8B.2 Quantitative Applications 247
8B.3 Qualitative Applications 254
8B.4 Evaluating Precipitation Gravimetry 254
8C Volatilization Gravimetry 255
8C.1 Theory and Practice 255
8C.2 Quantitative Applications 259
8C.3 Evaluating Volatilization Gravimetry 262
8D Particulate Gravimetry 262
8D.1 Theory and Practice 263
8D.2 Quantitative Applications 264
8D.3 Evaluating Precipitation Gravimetry 265
8E Key Terms 265
8F Summary 266
8G Suggested Experiments 266
8H Problems 267
8I Suggested Readings 271
8J References 272

 

Chapter 9.
Titrimetric Methods of Analysis 273
9A Overview of Titrimetry 274
9A.1 Equivalence Points and End Points 274
9A.2 Volume as a Signal 274
9A.3 Titration Curves 275
9A.4 The Buret 277
9B Titrations Based on Acid–Base Reactions 278
9B.1 Acid–Base Titration Curves 279
9B.2 Selecting and Evaluating the
End Point 287
9B.3 Titrations in Nonaqueous Solvents 295
9B.4 Representative Method 296
9B.5 Quantitative Applications 298
9B.6 Qualitative Applications 308
9B.7 Characterization Applications 309
9B.8 Evaluation of Acid–Base Titrimetry 311
9C Titrations Based on Complexation Reactions 314
9C.1 Chemistry and Properties of EDTA 315
9C.2 Complexometric EDTA Titration Curves 317
9C.3 Selecting and Evaluating the End Point 322
9C.4 Representative Method 324
9C.5 Quantitative Applications 327
9C.6 Evaluation of Complexation Titrimetry 331
9D Titrations Based on Redox Reactions 331
9D.1 Redox Titration Curves 332
9D.2 Selecting and Evaluating the End Point 337
9D.3 Representative Method 340
9D.4 Quantitative Applications 341
9D.5 Evaluation of Redox Titrimetry 350
9E Precipitation Titrations 350
9E.1 Titration Curves 350
9E.2 Selecting and Evaluating the End Point 354
9E.3 Quantitative Applications 354
9E.4 Evaluation of Precipitation Titrimetry 357
9F Key Terms 357
9G Summary 357
9H Suggested Experiments 358
9I Problems 360
9J Suggested Readings 366
9K References 367

 

Chapter 10.
Spectroscopic Methods
of Analysis 368
10A Overview of Spectroscopy 369
10A.1 What Is Electromagnetic Radiation 369
10A.2 Measuring Photons as a Signal 372
10B Basic Components of Spectroscopic
Instrumentation 374
10B.1 Sources of Energy 375
10B.2 Wavelength Selection 376
10B.3 Detectors 379
10B.4 Signal Processors 380
10C Spectroscopy Based on Absorption 380
10C.1 Absorbance of Electromagnetic Radiation 380
10C.2 Transmittance and Absorbance 384
10C.3 Absorbance and Concentration: Beer’s
Law 385
10C.4 Beer’s Law and Multicomponent
Samples 386
10C.5 Limitations to Beer’s Law 386
10D Ultraviolet-Visible and Infrared
Spectrophotometry 388
10D.1 Instrumentation 388
10D.2 Quantitative Applications 394
10D.3 Qualitative Applications 402
10D.4 Characterization Applications 403
10D.5 Evaluation 409
10E Atomic Absorption Spectroscopy 412
10E.1 Instrumentation 412
10E.2 Quantitative Applications 415
10E.3 Evaluation 422
10F Spectroscopy Based on Emission 423
10G Molecular Photoluminescence
Spectroscopy 423
10G.1 Molecular Fluorescence and
Phosphorescence Spectra 424
10G.2 Instrumentation 427
10G.3 Quantitative Applications Using Molecular
Luminescence 429
10G.4 Evaluation 432
10H Atomic Emission Spectroscopy 434
10H.1 Atomic Emission Spectra 434
10H.2 Equipment 435
10H.3 Quantitative Applications 437
10H.4 Evaluation 440
10I Spectroscopy Based on Scattering 441
10I.1 Origin of Scattering 441
10I.2 Turbidimetry and Nephelometry 441
10J Key Terms 446
10K Summary 446
10L Suggested Experiments 447
10M Problems 450
10N Suggested Readings 458
10O References 459

 

Chapter 11.
Electrochemical Methods of Analysis 461
11A Classification of Electrochemical Methods 462
11A.1 Interfacial Electrochemical Methods 462
11A.2 Controlling and Measuring Current and
Potential 462

11B Potentiometric Methods of Analysis 465
11B.1 Potentiometric Measurements 466
11B.2 Reference Electrodes 471
11B.3 Metallic Indicator Electrodes 473
11B.4 Membrane Electrodes 475
11B.5 Quantitative Applications 485
11B.6 Evaluation 494
11C Coulometric Methods of Analysis 496
11C.1 Controlled-Potential Coulometry 497
11C.2 Controlled-Current Coulometry 499
11C.3 Quantitative Applications 501
11C.4 Characterization Applications 506
11C.5 Evaluation 507
11D Voltammetric Methods of Analysis 508
11D.1 Voltammetric Measurements 509
11D.2 Current in Voltammetry 510
11D.3 Shape of Voltammograms 513
11D.4 Quantitative and Qualitative Aspects
of Voltammetry 514
11D.5 Voltammetric Techniques 515
11D.6 Quantitative Applications 520
11D.7 Characterization Applications 527
11D.8 Evaluation 531
11E Key Terms 532
11F Summary 532
11G Suggested Experiments 533
11H Problems 535
11I Suggested Readings 540
11J References 541

 

Chapter 12.
Chromatographic and Electrophoretic
Methods 543
12A Overview of Analytical Separations 544
12A.1 The Problem with Simple
Separations 544
12A.2 A Better Way to Separate Mixtures 544
12A.3 Classifying Analytical Separations 546
12B General Theory of Column
Chromatography 547
12B.1 Chromatographic Resolution 549
12B.2 Capacity Factor 550
12B.3 Column Selectivity 552
12B.4 Column Efficiency 552
12B.5 Peak Capacity 554
12B.6 Nonideal Behavior 555
12C Optimizing Chromatographic Separations 556
12C.1 Using the Capacity Factor to Optimize
Resolution 556
12C.2 Using Column Selectivity to Optimize
Resolution 558
12C.3 Using Column Efficiency to Optimize
Resolution 559
12D Gas Chromatography 563
12D.1 Mobile Phase 563
12D.2 Chromatographic Columns 564
12D.3 Stationary Phases 565
12D.4 Sample Introduction 567
12D.5 Temperature Control 568
12D.6 Detectors for Gas Chromatography 569
12D.7 Quantitative Applications 571
12D.8 Qualitative Applications 575
12D.9 Representative Method 576
12D.10 Evaluation 577
12E High-Performance Liquid
Chromatography 578
12E.1 HPLC Columns 578
12E.2 Stationary Phases 579
12E.3 Mobile Phases 580
12E.4 HPLC Plumbing 583
12E.5 Sample Introduction 584
12E.6 Detectors for HPLC 584
12E.7 Quantitative Applications 586
12E.8 Representative Method 588
12E.9 Evaluation 589
12F Liquid–Solid Adsorption Chromatography 590
12G Ion-Exchange Chromatography 590
12H Size-Exclusion Chromatography 593
12I Supercritical Fluid Chromatography 596
12J Electrophoresis 597
12J.1 Theory of Capillary Electrophoresis 598
12J.2 Instrumentation 601
12J.3 Capillary Electrophoresis Methods 604
12J.4 Representative Method 607
12J.5 Evaluation 609
12K Key Terms 609
12L Summary 610
12M Suggested Experiments 610
12N Problems 615
12O Suggested Readings 620
12P References 620

 

Chapter 13.
Kinetic Methods of Analysis 622
13A Methods Based on Chemical Kinetics 623
13A.1 Theory and Practice 624
13A.2 Instrumentation 634
13A.3 Quantitative Applications 636
13A.4 Characterization Applications 638
13A.5 Evaluation of Chemical Kinetic
Methods 639
13B Radiochemical Methods of Analysis 642
13B.1 Theory and Practice 643
13B.2 Instrumentation 643
13B.3 Quantitative Applications 644
13B.4 Characterization Applications 647
13B.5 Evaluation 648
13C Flow Injection Analysis 649
13C.1 Theory and Practice 649
13C.2 Instrumentation 651
13C.3 Quantitative Applications 655
13C.4 Evaluation 658
13D Key Terms 658
13E Summary 659
13F Suggested Experiments 659
13G Problems 661
13H Suggested Readings 664
13I References 665

 

Chapter 14.
Developing a Standard Method 666
14A Optimizing the Experimental Procedure 667
14A.1 Response Surfaces 667
14A.2 Searching Algorithms for Response
Surfaces 668
14A.3 Mathematical Models of Response
Surfaces 674
14B Verifying the Method 683
14B.1 Single-Operator Characteristics 683
14B.2 Blind Analysis of Standard Samples 683
14B.3 Ruggedness Testing 684
14B.4 Equivalency Testing 687
14C Validating the Method as a Standard
Method 687
14C.1 Two-Sample Collaborative Testing 688
14C.2 Collaborative Testing and Analysis of
Variance 693
14C.3 What Is a Reasonable Result for a
Collaborative Study? 698
14D Key Terms 699
14E Summary 699
14F Suggested Experiments 699
14G Problems 700
14H Suggested Readings 704
14I References 704

 

Chapter 15.
Quality Assurance 705
15A Quality Control 706
15B Quality Assessment 708
15B.1 Internal Methods of Quality
Assessment 708
15B.2 External Methods of Quality
Assessment 711
15C Evaluating Quality Assurance Data 712
15C.1 Prescriptive Approach 712
15C.2 Performance-Based Approach 714
15D Key Terms 721
15E Summary 722
15F Suggested Experiments 722
15G Problems 722
15H Suggested Readings 724
15I References 724

 

Appendixes
Appendix 1A Single-Sided Normal Distribution 725
Appendix 1B t-Table 726
Appendix 1C F-Table 727
Appendix 1D Critical Values for Q-Test 728
Appendix 1E Random Number Table 728
Appendix 2 Recommended Reagents for Preparing Primary
Standards 729
Appendix 3A Solubility Products 731
Appendix 3B Acid Dissociation Constants 732
Appendix 3C Metal–Ligand Formation Constants 739
Appendix 3D Standard Reduction Potentials 743
Appendix 3E Selected Polarographic Half-Wave Potentials 747
Appendix 4 Balancing Redox Reactions 748
Appendix 5 Review of Chemical Kinetics 750
Appendix 6 Countercurrent Separations 755
Appendix 7 Answers to Selected Problems 762
Glossary 769
Index 781

MODERN ANALYTICAL CHEMISTRY
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Colorplate 12: Courtesy of Hewlett-Packard Company; Colorplate 13: © David Harvey.
Library of Congress Cataloging-in-Publication Data
Harvey, David, 1956–
Modern analytical chemistry / David Harvey. — 1st ed.
p. cm.
Includes bibliographical references and index.
ISBN 0–07–237547–7
1. Chemistry, Analytic. I. Title.
QD75.2.H374 2000
543—dc21 99–15120
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INTERNATIONAL EDITION ISBN 0–07–116953–9
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