VOLUMETRIC PROPERTIES OF 1-1 AQUEOUS-ELECTROLYTE SOLUTIONS AND IONIC HYDRATION

A simple model based on the hypothesis of existence of hydration spheres and their overlap with increasing the salt concentration is proposed. A expression for the volumetric properties of 1-1 aqueous electrolyte solutions is derived in terms of a consistent set of parameters related to the volumetric properties of the hydration spheres. Such a model is applied to study the concentration dependence of the molar volume, compressibility and expansivity of aqueous sodium chloride solutions at different values of temperature and pressure. The concentration dependence of the molar volume of some aqueous alkali halides at 20 °C is also discussed. © 1990 American Institute of Physics.