Basics of Analytical Chemistry and Chemical Equilibria (eBook)

BRIAN M. TISSUE, PhD, is Associate Professor of Chemistry at Virginia Tech, where he teaches analytical chemistry at both the undergraduate and graduate levels. In addition to curriculum development, Dr. Tissue oversees a research program in nanomaterials and analytical spectroscopy, preparing and testing nanocomposites for catalytic activity. Among his honors, Dr. Tissue has received an NSF Career Award and a Cottrell Scholar Award from the Research Corporation for Science Advancement.

Preface ix

I Quantitative Analysis Using Reactions That Go To ''Completion'' 1

1 Making Measurements 3

1.1 Introduction 3

1.2 GLP and a Few Other Important Acronyms 10

1.3 Precision and Random Error 15

1.4 Discarding a Suspected Outlier 25

1.5 Calibration 28

1.6 Maintaining Accurate Results 43

Practice Exercises 48

2 Sample Preparation, Extractions, and Chromatography 53

2.1 Sampling and Control Samples 53

2.2 Sample Preparation 58

2.3 Solvents and Solutions 64

2.4 Introduction to Solubility 69

2.5 Extraction 71

2.6 Stationary Phases 82

2.7 Solid-Phase Extraction (SPE) 88

2.8 Introduction to Chromatography 91

2.9 Immunoassays 96

Practice Exercises 97

3 Classical Methods 103

3.1 Introduction 103

3.2 Review of Chemical Reactions 105

3.3 Reactions in Aqueous Solution 111

3.4 Gravimetry 120

3.5 Titration 124

3.6 Titration Curves 132

3.7 Coulometry 134

Practice Exercises 137

4 Molecular Spectroscopy 141

4.1 Introduction 141

4.2 Properties of EM Radiation 142

4.3 Electromagnetic Spectrum 146

4.4 Spectroscopic Transitions 147

4.5 UV/Vis Absorption Spectroscopy 154

4.6 UV/Vis Instrumentation 156

4.7 Beer-Lambert Law 159

4.8 Molecular Fluorescence 167

Practice Exercises 171

II Reactions That Do Not Go To ''Completion.'' Equilibria in Aqueous Solutions 177

5 Acid-Base Equilibria and Activity 179

5.1 Acids and Bases 179

5.2 Weak Acids and Weak Bases 186

5.3 Water and Kw 190

5.4 Acid Strength 196

5.5 The Concept of Activity 199

5.6 Acid-Base Equilibrium Calculations 212

Practice Exercises 218

6 Buffer Solutions and Polyprotic Acids 221

6.1 Buffer Solutions 221

6.2 Alpha Fraction Plots 226

6.3 Weak Acid Titration Curve 230

6.4 Polyprotic Acids 233

Practice Exercises 242

7 Complexation and Precipitation Equilibria 245

7.1 Complex Terminology 246

7.2 Complex Equilibria 249

7.3 Competing Equilibria 256

7.4 Stepwise Complexation 263

7.5 Precipitate Equilibrium 267

7.6 Molar Solubility 275

7.7 Precipitation and Competing Equilibria 282

Practice Exercises 287

III Instrumental Methods and Analytical Separations 293

8 Electroanalytical Chemistry 295

8.1 Introduction 295

8.2 Standard Reduction Potentials 298

8.3 Using Half Reactions 302

8.4 Background on Spontaneous Reactions and Equilibrium 308

8.5 Reaction Energies, Voltages, and the Nernst Equation 311

8.6 Electrochemical Cells 314

8.7 Potentiometry 319

8.8 Ion-Selective Electrodes (ISE) 322

8.9 Voltammetry 328

Practice Exercises 336

9 Atomic Spectrometry 340

9.1 Atomization 342

9.2 Atomic Absorption Spectrometry (AAS) 346

9.3 Atomic Emission Spectrometry (AES) 354

9.4 Introduction to Mass Spectrometry (MS) 357

9.5 ICP-MS Measurements 361

9.6 Summary 362

Practice Exercises 364

10 Analytical Separations 367

10.1 Thin-Layer Chromatography 368

10.2 Chromatogram Terminology 372

10.3 Column Selection 375

10.4 High Performance Liquid Chromatography 380

10.5 Gas Chromatography 388

10.6 Molecular Mass Spectrometry 390

10.7 Electrophoresis 398

Practice Exercises 402

Index 407