Electrochemical Investigation of Liquid Amalgams of Thallium, Indium, Tin, Zinc, Cadmium, Lead, Copper, and Lithium (Classic Reprint)

Theodore William Richards

Excerpt from Electrochemical Investigation of Liquid Amalgams of Thallium, Indium, Tin, Zinc, Cadmium, Lead, Copper, and Lithium The change in free energy during a chemical reaction may be regarded as composed of at least two separate quantities, one which may be said to be due to the affinities involved in the reaction, the other depending upon the relative concentration of initial substances and products. The calcula tion of the magnitudes Of these quantities is a matter of prime importance, for free energy is the driving agency of all earthly things. Unfortunately the actual determination of Changes of free energy is only possible in the case of easily reversible reactions, and these form a comparatively small part of many examples of chemical change. Of great theoretical importance in this connection are the reversible galvanic cells, which involve in their action simply the dilution of liquid amalgams, and consequently suffer no appreciable change of heat capacity. The study of such cells can furnish much light upon the second of the two independent quantities which together constitute the total free energy of a reaction, namely, concentration effect. Von Tiirin pointed out the analogy between such cells and the concentration elements first investi gated by Helmholtz and offered the first consistent theory of amalgam cells. G. Meyer measured cells Of this type, but much more accurate data have been obtained at Harvard University. The object of this recent work, which concerned itself with cells containing zinc and cadmium amalgams over a considerable range of concentration, was to test the application of the gas law to solutions of this type, as well as to apply the equations of Helmholtz and of Cady to the data. Great accuracy was sought. Since the two metals presented widely different phenomena, and since both of these metals are bivalent, it seemed desirable to extend the work by meas uring similar cells, employing a wide variety of other metals with other valencies. In this way a more complete survey of the possibilities would certainly be obtained. 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.