A Method For The Identification Of Pure Organic Compounds By A Systematic Analytical Procedure Based On Physical Properties And Chemical Reactions V 3 1911

Author : Samuel Parsons Mulliken
Publisher :
ISBN 13 : 9781332592074
Total Pages : 284 pages
Book Rating : 4.5/5 (92 download)

DOWNLOAD NOW!

Download or read book A Method for the Identification of Pure Organic Compounds, Vol. 1 written by Samuel Parsons Mulliken and published by . This book was released on 2016-06-16 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt: Excerpt from A Method for the Identification of Pure Organic Compounds, Vol. 1: By a Systematic Analytical Procedure Based on Physical Properties and Chemical Reactions At the time of writing the only general and fairly systematic procedure for the identification of previously described organic compounds of all classes is that which may be conveniently designated the Method of the Empirical Formula. In following this procedure a determination of the percentage composition is first made. The molecular weight is next determined or conjectured. From these data an empirical formula is calculated. The properties of the substance are then compared with those of all the known compounds possessing this formula by reference to their scattered literature, for which Richter's "Lexicon der Kohlenstoff-Verbindungen" with its supplements now furnishes a very complete index. Resting, as it chiefly does, on the two fundamental properties, percentage composition and molecular weight - which alone among the chemical constants can be readily calculated for every compound in advance of its discovery - it is probable that this method will long remain the last resort in all earnest attempts to establish the identity of compounds which have been previously undescribed or very imperfectly characterized through their physical and chemical properties. Nevertheless, when we turn to the great body of well-characterized compounds that occur with some frequency in the products of Nature, the useful arts, and the scientific laboratory, there is good reason to raise the question whether the Method of the Empirical Formula is from the practical standpoint a sufficiently satisfactory one. It is evidently not, if any substitute can be found that will lead the analyst to the same results with less expenditure of time and effort, and without requiring unusual knowledge or skill on his part; and it is not to be denied that in these respects this method makes a very poor showing. The indispensable key to its use is proficiency in ultimate organic analysis, whose difficult technique is fully mastered only by long practice. The performance of the combustions, which must be made in duplicate to secure certainty, is at best a time-consuming operation; and even after reliable results have been obtained, it is further necessary, in order to fully identify a compound, to resort to a study of its physical properties, chemical behavior, and perhaps to a molecular-weight determination. The consequence of this has been that the identification of organic compounds by this general method has been practically limited to its occasional employment in laboratories devoted to synthetic organic research, and that such identifications when attempted elsewhere are usually accomplished, often with uncertain results, by the use of disconnected desultory tests. Through these considerations, and with the belief that a path of less resistance could be broken out for the analyst, the writer began more than eight years ago the studies whose first results appear in this volume. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.