Analytical Chemistry An Introduction

by Skoog, Douglas A.; West, Donald M.; Holler, F. James; Crouch, Stanley R.

• ISBN13: 9780030202933
• ISBN10: 0030202930
• Edition: 7th
• Format: Hardcover
• Copyright: 1999-08-23
• Publisher: Cengage Learning

Summary

The new edition highlights some of the latest techniques such as supercritical fluid chromatography and capillary electrophoresis. The addition of spreadsheet exercises and problems throughout the text provides students with a more modern approach to analytical chemistry.

Table of Contents

Preface	xvii
1 What Is Analytical Chemistry?	1	(18)
1A The Role of Analytical Chemistry	2	(2)
1B Classifying Quantitative Analytical Methods	4	(1)
1C Stepping Through a Typical Quantitative Analysis	5	(5)
1D An Integral Role for Chemical Analysis: Feedback Control Systems	10	(9)
FEATURES
1-1 Deer Kill: A Case Study Illustrating the Use of Analytical Chemistry to Solve a Problem in Toxicology	12	(7)
Section I The Tools of Analytical Chemistry	19	(158)
2 The Tools of Analytical Chemistry	21	(40)
2A Selecting and Handling Reagents and Other Chemicals	22	(1)
2B Cleaning and Marking Laboratory Ware	23	(1)
2C Evaporating Liquids	24	(1)
2D Measuring Mass	24	(7)
2E The Equipment and Manipulations Associated with Weighing	31	(4)
2F The Equipment and Manipulations for Filtration and Ignition	35	(6)
2G Measuring Volume	41	(9)
2H Calibrating Volumetric Ware	50	(2)
2I The Laboratory Notebook	52	(2)
2J Using Spreadsheets in Analytical Chemistry	54	(5)
2K Safety in the Laboratory	59	(2)
3 Important Chemical Concepts: Expressing Quantities and Concentrations	61	(18)
3A Some Important Units of Measurement	61	(4)
3B Solutions and Their Concentrations	65	(8)
3C Chemical Stoichiometry	73	(3)
3D Questions and Problems	76
FEATURES
3-1 Distinguishing between Mass and Weight	63
3-2 Atomic Mass Units and the Mole	64
3-3 Another Approach to Example 3-2	66
4 The Basic Approach to Chemical Equilibrium	79	(24)
4A The Chemical Composition of Aqueous Solutions	79	(4)
4B Chemical Equilibrium	83	(18)
WEB WORKS	101	(1)
4C Questions and Problems	101
FEATURES
4-1 Amphiprotic Species	81
4-2 Stepwise and Overall Formation Constants for Complex Ions	86
4-3 Why [H(2)O} Does Not Appear in Equilibrium-Constant Expressions for Aqueous Solutions	87
4-4 Relative Strengths of Conjugate Acid/Base Pairs	93
4-5 The Method of Successive Approximations	97
5 Errors in Chemical Analyses: How Certain Can We Be?	103	(14)
5A Defining Terms	104	(4)
5B Systematic Errors	108	(8)
WEB WORKS	116	(1)
5C Questions and Problems	116	(1)
6 Random Error: How Certain Can We Be?	117	(32)
6A The Nature of Random Errors	117	(3)
6B Treating Random Errors with Statistics	120	(19)
6C The Standard Deviation of Computed Results	139	(3)
6D Reporting Computed Data	142	(4)
WEB WORKS	146	(1)
6E Questions and Problems	146
FEATURES
6-1 Flipping Coins: A Student Activity to Illustrate a Normal Distribution	121
6-2 How Do You Calculate Those Areas under a Curve?	124
6-3 The Significance of Number of Degrees of Freedom	126
6-4 Equation for Calculating Pooled Standard Deviations	134
7 Statistical Analysis: Evaluating the Data	149	(28)
7A Confidence Limits	149	(4)
7B Statistical Aids to Hypothesis Testing	153	(4)
7C Detecting Gross Errors	157	(3)
7D Analyzing Two-Dimensional Data: The Least Squares Method	160	(13)
WEB WORKS	172	(1)
7E Questions and Problems	173	(4)
Section II Principles and Applications of Chemical Equilibria	177	(210)
8 Gravimetric Methods of Analysis	179	(25)
8A Properties of Precipitates and Precipitating Reagents	180	(11)
8B Drying and Ignition of Precipitates	191	(1)
8C Calculating Results from Gravimetric Data	192	(2)
8D Applications of Gravimetric Methods	194	(7)
WEB WORKS	201	(1)
8E Questions and Problems	201
FEATURES
8-1 Specific Surface Area of Colloids	187
9 Electrolyte Effects: Activity or Concentration?	204	(17)
9A Effects of Electrolytes on Chemical Equilibria	204	(3)
9B Activity Coefficients	207	(12)
WEB WORKS	219	(1)
9C Questions and Problems	219
FEATURES
9-1 Mean Activity Coefficients	211
10 How Equilibrium Calculations Can Be Applied to Complex Systems	221	(25)
10A Solving Multiple-Equilibrium Problems by a Systematic Method	222	(4)
10B Calculating Solubilities by the Systematic Method	226	(6)
10C Separating Ions by pH Control: Sulfide Separations	232	(12)
WEB WORKS	244	(1)
10D Questions and Problems	244
FEATURES
10-1 Algebraic Expressions Needed to Calculate Solubility of CaC(2)O(4) Water	231
10-2 Immunoassay: Equilibria in the Specific Determination of Drugs	235
11 Titrations: Taking Advantage of Stoichiometric Reactions	246	(19)
11A Some General Aspects of Volumetric Titrimetry	247	(2)
11B Standard Solutions	249	(1)
11C Volumetric Calculations	250	(8)
11D Titration Curves	258	(3)
WEB WORKS	261	(1)
11E Questions and Problems	261
FEATURES
11-1 The Factor-Label Approach to Example 11-6	255
11-2 How Did We Calculate the Volumes of NaOH Shown in the First Column of Table 11-1?	260
12 Principles of Neutralization Titrations: Determining Acids, Bases, and the pH of Buffer Solutions	265	(38)
12A What Solutions and Indicators Are Used?	265	(4)
12B Calculating pH in Titrations of Strong Acids and Strong Bases	269	(7)
12C Buffer Solutions	276	(11)
12D Calculating pH in Weak Acid Titrations	287	(6)
12E Calculating pH in Titrations of Weak Bases	293	(4)
12F How Do Buffer Solutions Change as a Function of pH?	297	(2)
WEB WORKS	299	(1)
12G Questions and Problems	299
FEATURES
12-1 Constructing Titration Curves from the Charge-Balance Equation	274
12-2 How Many Significant Figures Should We Retain in Titration Curve Calculations?	275
12-3 Applying the Systematic Method to Buffer Calculations	277
12-4 The Henderson-Hasselbach Equation	278
12-5 Acid Rain and the Buffer Capacity of Lakes	282
12-6 Determining Dissociation Constants for Weak Acids and Bases	291
12-7 Determining the pK Values for Amino Acids	295
13 Titrating Polyfunctional Acids and Bases	303	(24)
13A Polyfunctional Acids	303	(1)
13B Describing Polyfunctional Bases	303	(2)
13C Finding the pH of Solutions of Amphiprotic Salts	305	(3)
13D Constructing Titration Curves for Polyfunctional Acids	308	(6)
13E Drawing Titration Curves for Polyfunctional Bases	314	(3)
13F The Composition of Polyprotic Acid Solutions as a Function of pH	317	(7)
WEB WORKS	324	(1)
13G Questions and Problems	324
FEATURES
13-1 Combining Equilibrium-Constant Expressions	304
13-2 How Was Equation 13-3 Generated?	306
13-3 The Dissociation of Sulfuric Acid	314
13-4 Titration Curves for Amino Acids	316
13-5 A General Expression for Alpha Values	318
14 Applying Neutralization Titrations	327	(18)
14A Reagents for Neutralization Titrations	327	(6)
14B Typical Applications of Neutralization Titrations	333	(7)
WEB WORKS	340	(1)
14C Questions and Problems	340
FEATURES
14-1 Determining Total Serum Protein	334
14-2 Other Methods for Determining Organic Nitrogen	335
15 Complexation and Precipitation Titrations: Taking Advantage of Complexing and Precipitating Agents	345	(42)
15A Forming Complexes	345	(6)
15B Titrations with Inorganic Complexing Agents	351	(8)
15C Organic Complexing Agents	359	(2)
15D Titrations with Aminocarboxylic Acids	361	(22)
WEB WORKS	382	(1)
15E Questions and Problems	383
FEATURES
15-1 Determination of Hydrogen Cyanide in Acrylonitrile Plant Streams	353
15-2 Species Present in a Solution of EDTA	362
15-3 EDTA as a Preservative	364
15-4 How Can Masking and Demasking Agents Be Used to Enhance the Selectivity of EDTA Titrations?	381
15-5 Test Kits for Water Hardness	382
Section III Electrochemical Methods	387	(158)
16 Elements of Electrochemistry	389	(30)
16A Characterizing Oxidation/Reduction Reactions	389	(5)
16B Electrochemical Cells	394	(3)
16C Electrode Potentials	397	(19)
WEB WORKS	415	(1)
16D Questions and Problems	416
FEATURES
16-1 Balancing Redox Equations	391
16-2 The Daniell Gravity Cell	396
16-3 Why We Cannot Measure Absolute Electrode Potentials	401
16-4 Sign Conventions in the Older Literature	411
16-5 Why Are There Two Electrode Potentials for Br(2) in Table 16-1?	413
17 Using Electrode Potentials	419	(25)
17A Calculating Potentials of Electrochemical Cells	419	(4)
17B Calculating Redox Equilibrium Constants	423	(5)
17C Constructing Redox Titration Curves	428	(11)
17D Oxidation/Reduction Indicators	439	(2)
17E Potentiometric End Points	441	(1)
WEB WORKS	441	(1)
17F Questions and Problems	442
FEATURES
17-1 Biological Redox Systems	424
18 Applying Oxidation/Reduction Titrations	444	(27)
18A Auxiliary Oxidizing and Reducing Reagents	444	(2)
18B Applying Standard Reducing Agents	446	(4)
18C Applying Standard Oxidizing Agents	450	(17)
WEB WORKS	466	(1)
18D Questions and Problems	467
FEATURES
18-1 Determination of Chromium Species in Water Samples	453
18-2 Antioxidants	458
19 Potentiometry: Measuring Concentrations of Ions and Molecules	471	(37)
19A General Principles	471	(1)
19B What Reference Electrodes Are Used?	472	(2)
19C Dealing with Liquid-Junction Potentials	474	(1)
19D Indicator Electrodes	475	(18)
19E Instruments for Measuring Cell Potential	493	(1)
19F Direct Potentiometry	493	(6)
19G Following Titrations by Potentiometry	499	(6)
WEB WORKS	505	(1)
19H Questions and Problems	505
FEATURES
19-1 An Easily Constructed Liquid-Membrane Ion-Selective Electrode	487
19-2 Point-of-Care Testing: Blood Gases and Blood Electrolytes with Portable Instrumentation	490
20 A Brief Look at Some Other Electroanalytical Methods	508	(37)
20A How Does Current Affect the Potential of Electrochemical Cells?	509	(6)
20B Are Electrolytic Methods Selective?	515	(1)
20C Electrogravimetric Methods: Weighing the Deposit	516	(6)
20D Coulometric Methods of Analysis	522	(9)
20E Voltammetry	531	(8)
20F Some Additional Electroanalytical Methods	539	(1)
WEB WORKS	540	(1)
20G Questions and Problems	540
FEATURES
20-1 Overvoltage and the Lead-Acid Battery	515
Section IV Spectrochemical Analysis	545	(92)
21 Spectroscopic Methods of Analysis: Making Measurements with Light	547	(25)
21A Light: A Particle, a Wave, or Both?	548	(2)
21B How Radiation and Matter Interact	550	(5)
21C Absorbing Light	555	(13)
WEB WORKS	568	(1)
21D Questions and Problems	568
FEATURES
21-1 Spectroscopy and the Discovery of Elements	554
21-2 Why Is a Red Solution Red?	565
22 Instruments for Measuring Absorption: Is It a Photometer, a Spectrophotometer, or a Spectrometer?	572	(22)
22A Instrument Components	572	(14)
22B UV/Visible Photometers and Spectrophotometers	586	(4)
22C Infrared Spectrophotometers	590	(2)
WEB WORKS	592	(1)
22D Questions and Problems	592
FEATURES
22-1 Gratings Rule 57
23 Applying Molecular and Atomic Spectroscopic Methods: Shedding More Light on the Subject	594	(43)
23A Applying Ultraviolet/Visible Molecular Absorption Methods	595	(16)
23B Absorbing Infrared Radiation: Good Vibrations	611	(4)
23C Assessing Errors in Spectrophotometry	615	(1)
23D Molecular Luminescence Spectroscopy	616	(9)
23E Molecular Scattering Methods	625	(1)
23F Atomic Spectroscopy	626	(6)
WEB WORKS	631	(1)
23G Questions and Problems	632
FEATURES
23-1 Infrared Photometers for Routine Determination of Atmospheric Pollutants	614
23-2 How Is Fluorescence Related to Concentration?	620
23-3 Use of Fluorescence Probes in Neurobiology: Probing the Enlightened Mind	622
23-4 Mercury and Its Determination by Cold-Vapor Atomic Absorption Spectroscopy	628
Section V Separation Methods	637	(82)
24 An Introduction to Analytical Separations	638	(29)
24A Masking	638	(1)
24B Precipitation and Filtration	639	(1)
24C Separating Species by Distillation	639	(1)
24D Separating Solutes by Extraction	640	(4)
24E Separating Ions by Ion Exchange	644	(2)
24F Chromatographic Separations	646	(17)
WEB WORKS	663	(1)
24G Questions and Problems	663
FEATURES
24-1 Derivation of Equation 24-2	641
24-2 What Is the Source of the Terms Plate and Plate Height?	658
25 Gas-Liquid and High-Performance Fluid Chromatography	667	(33)
25A Gas-Liquid Chromatography	667	(16)
25B High-Performance Liquid Chromatography	683	(12)
25C High-Performance Liquid Chromatography versus Gas-Liquid Chromatography	695	(3)
WEB WORKS	698	(1)
25D Questions and Problems	698
FEATURES
25-1 Use of Gas Chromatography/Mass Spectrometry to Identify a Drug Metabolite in Blood	679
25-2 Buckyballs: The Chromatographic Separation of Fullerenes	696
26 Supercritical-Fluid Chromatography, Capillary Electrophoresis, and Capillary Electrochromatography	700	(19)
26A Supercritical-Fluid Chromatography	700	(5)
26B Capillary Electrophoresis	705	(10)
26C Capillary Electrochromatography	715	(3)
WEB WORKS	717	(1)
26D Questions and Problems	718	(1)
Section VI Selected Methods of Analysis	719
27 Selected Methods of Analysis	721
27A An Introductory Experiment	723	(5)
27B Gravimetric Methods of Analysis	728	(4)
27C Neutralization Titrations	732	(8)
27D Precipitation Titrations	740	(1)
27E Complex-Formation Titrations with EDTA	741	(2)
27F Titrations with Potassium Permanganate	743	(6)
27G Titrations with Iodine	749	(3)
27H Titrations with Sodium Thiosulfate	752	(3)
27I Titrations with Potassium Bromate	755	(2)
27J Potentiometric Methods	757	(5)
27K Electrogravimetric Methods	762	(2)
27L Methods Based on the Absorption of Radiation	764	(4)
27M Atomic Spectroscopy	768	(2)
27N Separating Cations by Ion Exchange	770	(2)
27O Gas-Liquid Chromatography	772
WEB WORKS	773
Appendix 1 Solubility Product Constants at 25^(Degree)C	A-1	(2)
Appendix 2 Acid Dissociation Constants at 25^(Degree)C	A-3	(2)
Appendix 3 Formation Constants of Complex Compounds at 25^(Degree)C	A-5	(2)
Appendix 4 Standard and Formal Electrode Potentials	A-7	(3)
Appendix 5 Use of Exponential Numbers and Logarithms	A-10	(5)
Appendix 6 Volumetric Calculations Using Normality and Equivalent Weight	A-15	(8)
Appendix 7 Acronyms and Abbreviations of Significance in Analytical Chemistry	A-23	(2)
Answers to Selected Questions and Problems	A-25
Glossary	G-1
Index	I-1