THERMODYNAMICS OF AQUEOUS ELECTROLYTE SOLUTIONS AT HIGH TEMPERATURES AND PRESSURES (HEAT CAPACITY, CUBIC SPLINE, DENSITY)

This dissertation contains five chapters and this abstract will describe the chapters separately.;Chapter 2. The volumetric properties of aqueous NaCl, MgCl(,2), KCl, NaBr, LiCl and CaCl(,2) solutions have been measured from 0.1 to 40 MPa and 0.05 to 5.0 mol kg('-1) at 298 K. These data have been compared with available literature data. Polynomial representations are also included.;Chapter 3. A highly flexible method of representing multi-dimensional surfaces is proposed. This method of representation is applied to apparent molar heat capacity data of aqueous NaCl solutions. The resulting surface is used to calculate the temperature dependence of free energy and enthalpies. A calculation of the effect of varying the Debye-Huckel limiting law slopes is also included.;Chapter 4. Multi-dimensional cubic spline surfaces have been generated for the apparent molar heat capacity of aqueous MgCl(,2), KCl, NaBr, LiCl, and CaCl(,2) solutions. The temperature dependence of free energy and enthalpy are calculated over each surface. Comparisons with experimental data are made wherever possible.;Chapter 1. Marshall and Franck have given an equation for the ionization constant of water as a function of temperature and density. The partial molar heat capacities and volumes at infinite dilution for the "electrolyte" H('+)(aq) + OH('-)(aq) have been calculated. Calculations using the Born equations predict the same qualitative behavior although quantitative prediction with a single radius is not possible.;Chapter 5. The volumetric properties of aqueous NaCl and CaCl(,2) solutions have been measured from 0.05 to 5.0 mol kg('-1) and 373 to 600 K. These data are represented by a multi-dimensional cubic spline surface which is compared to available literature data.