Page iii Principles and Practice of Analytical Chemistry Fifth Edition F.W. Fifield Kingston University and D. Kealey University of Surrey Page iv © 2000 by Blackwell Science Ltd Editorial Offices: Osney Mead, Oxford OX2 0EL 25 John Street, London WC1N 2BL 23 Ainslie Place, Edinburgh EH3 6AJ 350 Main Street, Malden MA 02148 5018, USA 54 University Street, Carlton Victoria 3053, Australia 10, rue Casimir Delavigne 75006 Paris, France Other Editorial Offices: Blackwell Wissenschafts-Verlag GmbH Kurfürstendamm 57 10707 Berlin, Germany Blackwell Science KK MG Kodenmacho Building 7–10 Kodenmacho Nihombashi Chuo-ku, Tokyo 104, Japan The right of the Authors to be identified as the Authors of this Work has been asserted in accordance with the Copyright, Designs and Patents Act 1988. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, except as permitted by the UK Copyright, Designs and Patents Act 1988, without the prior permission of the publisher. First Edition published 1975 by Chapman & Hall Second Edition 1983 Third Edition 1990 Fourth Edition 1995 This Edition published 2000 Set in 10/12pt Times by DP Photosetting, Aylesbury, Bucks Printed and bound in the United Kingdom at the University Press, Cambridge The Blackwell Science logo is a trade mark of Blackwell Science Ltd, registered at the United Kingdom Trade Marks Registry DISTRIBUTORS Marston Book Services Ltd PO Box 269 Abingdon Oxon OX14 4YN (Orders: Tel: 01235 465500 Fax: 01235 465555) USA Blackwell Science, Inc. Commerce Place 350 Main Street Malden, MA 02148 5018 (Orders: Tel: 800 759 6102 781 388 8250 Fax: 781 388 8255) Canada Login Brothers Book Company 324 Saulteaux Crescent Winnipeg, Manitoba R3J 3T2 (Orders: Tel: 204 837-2987 Fax: 204 837-3116) Australia Blackwell Science Pty Ltd 54 University Street Carlton, Victoria 3053 (Orders: Tel: 03 9347 0300 Fax: 03 9347 5001) A catalogue record for this title is available from the British Library ISBN 0-632-05384-4 Library of Congress Cataloging-in-Publication Data Fifield, F.W. (Frederick William) Principles and practice of analytical chemistry/F.W. Fifield and D. Kealey. p. cm. Includes bibliographical references and index. ISBN 0-632-05384-4 (pbk). 1. Chemistry, Analytic. I. Kealey, D. (David) II. Title. QD75.2 .F53 2000 543 – dc21 99-059799 For further information on Blackwell Science, visit our website: www.blackwell-science.com Page v Contents Preface xi Acknowledgements xiii 1 1 Introduction The Scope of Analytical Chemistry. The Function of Analytical Chemistry. Analytical Problems and Their Solution. The Nature of Analytical Methods. Trends in Analytical Methods and Procedures. Glossary of Terms. 2 13 The Assessment of Analytical Data 2.1 Definitions and Basic Concepts 13 2.2 The Nature and Origin of Errors 16 2.3 The Evaluation of Results and Methods 17 The Reliability of Measurements. The Analysis of Data. The Application of Statistical Tests. Limits of Detection. Quality Control Charts. Standardization of Analytical Methods. Chemometrics. Problems 34 3 37 pH, Complexation and Solubility Equilibria 3.1 Chemical Reactions in Solution 38 Equilibrium Constants. Kinetic Factors in Equilibria. 3.2 Solvents in Analytical Chemistry 41 Ionizing Solvents. Non-ionizing Solvents. 3.3 Acid–base Equilibria 43 Weak Acid and Weak Base Equilibria. Buffers and pH Control. The pH of Salt Solutions. 3.4 Complexation Equilibria 49 The Formation of Complexes in Solution. The Chelate Effect. 3.5 Solubility Equilibria 52 Solubility Products. Problems 53 4 54 Separation Techniques 4.1 Solvent Extraction 55 Efficiency of Extraction. Selectivity of Extraction. Extraction Systems. Extraction of Uncharged Metal Chelates. Methods of Extraction. Applications of Solvent Extraction. 4.2 Solid Phase Extraction 73 Solid Phase Sorbents. Solid Phase Extraction Formats. Automated Solid Phase Extraction. Solid Phase Microextraction. Applications of SPE and SPME. Page vi 4.3 Chromatography 80 4.3.1 Gas Chromatography. 4.3.2 High Performance Liquid Chromatography. 4.3.3 Supercritical Fluid Chromatography. 4.3.4 Thin-layer Chromatography. 4.3.5 Ion-exchange Chromatography. 4.3.6 Size Exclusion Chromatography. 4.4 Electrophoresis 170 Factors Affecting Ionic Migration. Effect of Temperature. pH and Ionic Strength. Electro-osmosis. Supporting Medium. Detection of Separated Components. Applications of Traditional Zone Electrophoresis. High-performance Capillary Electrophoresis. Capillary Electrochromatography. Applications of Capillary Electrochromatography. Problems 188 5 191 Titrimetry and Gravimetry 5.1 Titrimetry 191 Definitions. Titrimetric Reactions. Acid-base Titrations. Applications of Acid–base Titrations. Redox Titrations. Applications of Redox Titrations. Complexometric Titrations. Ethylenediaminetetraacetic Acid (EDTA). Applications of EDTA Titrations. Titrations with Complexing Agents Other Than EDTA. Precipitation Titrations. 5.2 Gravimetry 216 Precipitation Reactions. Practical Gravimetric Procedures. Applications of Gravimetry. Problems 226 6 228 Electrochemical Techniques 6.1 Potentiometry 232 Electrode Systems. Direct Potentiometric Measurements. Potentiometric Titrations. Null-point Potentiometry. Applications of Potentiometry. 247 6.2 Polarography, Stripping Voltammetry and Amperometric Techniques Diffusion Currents. Half-wave Potentials. Characteristics of the DME. Quantitative Analysis. Modes of Operation Used in Polarography. The Dissolved Oxygen Electrode and Biochemical Enzyme Sensors. Amperometric Titrations. Applications of Polarography and Amperometric Titrations. 6.3 Electrogravimetry and Coulometry 260 Coulometry. Coulometry at Constant Potential. Coulometric Titrations. Applications of Coulometric Titrations. 6.4 Conductometric Titrations 264 Ionic Conductances. Problems 267 7 270 An Introduction to Analytical Spectrometry Electromagenetic Radiation. Atomic and Molecular Energy. The Absorption and Emission of Electromagnetic Radiation. The Complexity of Spectra and the Intensity of Spectral Lines. Analytical Spectrometry. Instrumentation. Page vii 8 284 Atomic Spectrometry 8.1 Arc/Spark Atomic (Optical) Emission Spectrometry 289 Instrumentation. Sample Preparation. Qualitative and Quantitative Analysis. Interferences and Errors Associated with the Excitation Process. Applications of Arc/Spark Emission Spectrometry. 8.2 Glow Discharge Atomic Emission Spectrometry 295 Instrumentation. Applications. 8.3 Plasma Emission Spectrometry 298 Instrumentation. Sample Introduction for Plasma Sources. Analytical Measurements. Applications of Plasma Emission Spectrometry. 8.4 Inductively Coupled Plasma–mass Spectrometry (ICP–MS) 305 Principles. Instrumentation. Applications. 8.5 Flame Emission Spectrometry 312 Instrumentation. Flame Characteristics. Flame Processes. Emission Spectra. Quantitative Measurements and Interferenccs. Applications of Flame Photometry and Flame Atomic Emission Spectrometry. 8.6 Atomic Absorption Spectrometry 320 Absorption of Characteristic Radiation. Instrumentation. Sample Vaporization. Quantitative Measurements and Interferences. Applications of Atomic Absorption Spectrometry. 8.7 Atomic Fluorescence Spectrometry 333 8.8 X-ray Emission Spectrometry 335 X-ray Processes. Instrumentation. Applications of X-ray Emission Spectrometry. Problems 352 9 354 Molecular Spectrometry 9.1 Visible and Ultraviolet Spectrometry 363 Polyatomic Organic Molecules. Metal Complexes. Qualitative Analysis – The Identification of Structural Features. Quantitative Analysis – Absorptiometry. Choice of Colorimetric and Spectrophotometric Procedures. Fluorimetry. Applications of UV/Visible Spectrometry and Fluorimetry. 9.2 Infrared Spectrometry 378 Diatomic Molecules. Polyatomic Molecules. Characteristic Vibration Frequencies. Factors Affecting Group Frequencies. Qualitative Anlaysis – The Identification of Structural Features. Quantitative Analysis. Sampling Procedures. Near Infrared Spectrometry. Applications of Infrared Spectrometry. 9.3 Nuclear Magnetic Resonance (NMR) Spectrometry 396 Instrumentation. The NMR Process. Chemical Shift. Spin–spin Coupling. Carbon-13 NMR. Pulsed Fourier transform NMR (FT- NMR). Qualitative Analysis – The Identification of Structural Features. Quantitative Analysis. Applications of NMR Spectrometry. 9.4 Mass Spectrometry 426 Instrumentation. Principle of Mass Spectrometry. Characteristics and Interpretation of Molecular Mass Spectra. Applications of Mass Spectrometry. 9.5 Spectrometric Identification of Organic Compounds 440