An Advanced Course of Instruction in Chemical Principles (Classic Reprint) PDF Download

Author: Arthur A. Noyes
Publisher:
ISBN: 9781330471029
Category : Science
Languages : en
Pages : 332

Get Book Here

Book Description
Excerpt from An Advanced Course of Instruction in Chemical Principles 1. Definition of the Field of Chemistry. Its General Principles the Subject of this Course.- Chemistry treats of the composition of substances, of their properties in relation to their composition, of changes in their composition, and of the effects attending such changes. General chemistry, often called also theoretical or physical chemistry, treats of the general principles which have been found to express certain common characteristics of the numerous phenomena of chemistry. To a discussion of the more important of these general principles this Course will be devoted. The divisions of the subject will be taken up in the order in which they were named in the above-given definition of the field of chemistry. 2. Pure Substances and Mixtures, and the Law of Definite Proportions.- Out of the materials occurring in nature there can be prepared substances which, when subjected to suitable processes of fractionation (that is, to operations which resolve the materials into parts or fractions), always yield fractions whose properties are identical when measured at the same pressure and temperature. Such substances are called pure substances; other substances which can be resolved by such processes into fractions with different properties being called mixtures. For example, whether a solid material is a pure substance or mixture may be determined by partially melting or vaporizing it or by partially dissolving it in solvents, and by comparing the value of the density, melting-point, or some other sensitive property, of the unmelted, unvaporized, or undissolved part with that of the original material. The fundamental idea involved in the preceding considerations is that there exists an order of substances, called pure substances, of relatively great stability toward resolving agencies, each one of which has a perfectly definite set of properties, sharply differentiated from those of other pure substances; so that there is not a continuous series of pure substances whose properties pass over into one another by insensible gradations. 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.