Chemistry of Specific, Selective and Sensitive Reactions [antikvár]

PREFACE During the past twenty-five years, analytical methods based on the properties and reactions of the substances to be detected or identified have been improved to a greater extent than in all the preceding years. This is shown by the steadily increasing number of new methods devised, by the many improvements and simplifications of older methods, and by the scientific explanations of the details of analytical procedures. This development in breadth and depth, as well as the coincidental development of instrumental methods of analysis has been stimulated by the idea that the goal of analytical work must be the identification and determination of the smallest possible quantity of a substance, even in the presence of other substances, using a minimum of material, time and working efforts, regardless of the technique involved. Thus, the greatest importance must be given to the specificity, selectivity and sensitivity of the analytical processes. The present book, based on many years of research and study of the literature, is an attempt to summarize our knowledge of the scientific background of the specificity, selectivity and sensitivity of analytical procedures. This indicates that the book is not a mere bibliography of chemical methods of identification and determination. The immediate object is to discover such regularities and rules as govern specificity, selectivity and sensitivity by examining the details of analytical procedures. Therefore, the mechanism of chemical reactions, the composition and constitution of the reacting substances and the products obtained, as well as the influence of the conditions under which the reactions take place, must be studied. Furthermore, the relationship between solubility, color, fluorescence, etc., and the constitution of compounds must be considered. Such an approach to analytical processes makes it necessary to pay careful attention to other fields of chemistry. It is obvious that pertinent material cannot be obtained from abstracts of analytical papers alone. Important facts and observations are often presented as apparently unimportant parts, sometimes even as footnotes, of original papers. Frequently, it is the interpretation of certain data by the author of a paper, or by other authors in later papers on the same or a similar subject, which leads to interesting and important conclusions. Publications in the field of inorganic and organic chemistry, colloid chemistry, photochemistry, etc., may also contain facts which are valuable vii