Volume Changes on Mixing for Binary Mixtures of Liquids
“Of the various thermodynamic functions for the mixing process, the volume change on mixing at constant pressure . . . is one of the most interesting, yet certainly still one of the least understood.” Hildebrand and Scott wrote this (1962) at a time when the subject of this review was entering a phase of renewed interest and development. This renewed interest is closely tied to the advances in the theories of solutions which were made in the 1960’s. For a long time the precision attainable on measuring volume changes on mixing was several orders of magnitude better than theory could calculate. The first breakthrough in the corresponding states theories was in predicting accurately the sign of the volume change on mixing. Current theories of solution are much more accurate with respect to sign and magnitude, and this has spawned a vigorous expansion in techniques and measurement. Although the subject of this review is narrowly restricted to volume changes on mixing, the theories discussed and the subject, itself, cannot be separated from the other excess thermodynamic properties of solutions. The subject will continue to be of interest in the 1970’s simply because the experiments are relatively easy to perform with great precision and because the volume change on mixing is a sensitive indicator to the accuracy of theories of solution.
(1971). Volume Changes on Mixing for Binary Mixtures of Liquids. Chemical Reviews, 71 (1), 5-45.