Contents
Chapter 1
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
Chapter 2
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
Chapter 3
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
Chapter 4
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
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 Errorsin y 119
5C.3 Weighted Linear Regression with Errorsin y 124
5C.4 Weighted Linear Regression with Errorsin 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
To download this book