Hydration Numbers and the State of Water in Hydration Spheres of Magnesium Chloride and Magnesium Sulfate Solutions

摘要

An equation for determining hydration numbers and molar adiabatic compressibilities has been derived by correct thermodynamic processing of a data set comprising ultrasound velocity, density, and iso-baric heat capacity in aqueous magnesium chloride and sulfate solutions for concentrations ranging from very dilute solutions to the complete solvation boundary and temperatures of 273.15-323.15 K. One basic innovation of the derived equation consists in that it accounts for the dependence of solvation numbers on solution concentration and in that all changes experienced by the solution are associated with the solvation of a sto-ichiometric mixture of electrolyte ions or nonelectrolytes molecules.