The compressibility of aqueous solutions II

Abstract

In an earlier communication, Perman and Urry described the measurement, by a direct method, of the compressibility coefficients of aqueous solution of urea, cane sugar, potassium chloride, and calcium chloride, over a range temperatures and concentrations. Their work was over the pressure range 0-200 atmospheres excess pressure. They were able to apply their together with other data obtained by their co-workers, to an extension Porter's theory of compressible solutions, and thus obtained values for osmotic pressures of those solutions which agreed very well with the obtained by more direct methods. The present work is a continuation of this and subsequent work (unpublished) by these authors. It was intended, especially, to investigate the effect of nature of the solute molecule upon the compressibility, and, for this reason the choice of solutes was particularly important. A number of series chemically related compounds were used where only one part of the mole varied in a progressive manner from substance to substance. In series there was no chemical relationship, but the members had the empirical formula and their molecular weights were therefore simple multi of each other.