This book contains electrolyte conductivity data of solutions in binary solvent mixtures of acetonitrile and propylene carbonate at electrolyte concentrations from high dilution to saturation in the temperature range from 238 K to 378 K over the whole mixing range of the solvent systems. Data analysis of conductivity data at low to moderate concentrations is based on the chemical model equation for partially associating electrolytes giving the association constant and limiting molar conductivity. For concentrated solution the empirical Casteel-Amis equation reproduces satisfactorily well conductivity as a function of molality from moderate concentrations up to saturation.
F.16 Improvements to an existing information system/databases
COBISS.SI-ID: 1536090307Understanding the aqueous solvation of electrolytes, polyelectrolytes and proteins, is important for chemistry, biology, as well as, for industry. In recent years we applied statistical mechanics to such systems. We used Wertheim’s integral equation theory, which is well suited for systems of molecules with directional forces. Such an approach is able to treat mixture of water molecules, ions and proteins, with all the species treated on equal footing. We will begin the presentation with aqueous solutions of alkali halides to show the effects of bare ionic sizes of salt forming ions on osmotic properties of the solution. Next, we will ask ourselves how the presence of hydrophobic groups on polyelectrolytes affects the solution energetics. We will conclude the presentation with discussion of the proteins self association. The theory will be supported by measurements.
B.04 Guest lecture
COBISS.SI-ID: 1537262531The ion specific effects in aqueous solutions are an important phenomena present in a large veriety of systems, from simple electrolyte solutions to complex biological systems. A common situation that occurs in aqueous solutions that are of biological, or technological importance, is the presence of polyions in the solutions. The structuring of water caused by the ionic charges is therefore modified by the presence of the hyrdophobic groups. We have studied the ion specific effects via computer simulations, as well as via experimental methods. Our results on aqueous polyelectrolyte solutions show that solution properties are determined by charged and uncharged groups, and that the effects are not additive. The presence of the hydrophobic groups may modify the Hofmeister series. To rationalize the ion specific effects, solvent has to be included in calculation explicitly.
B.04 Guest lecture
COBISS.SI-ID: 1537208771Isothermal titration calorimetry data for mixing ionene salts or poly(anethole sulfonates) salts with low molecular weight salts were presented. The influence of polyion hydrophobicity, charge density and the chemical nature of counterions on the mixing enthalpies in this solutions were discussed. Delicate balance between the ion and water interactions and the effects on the hydrogen-bonding structure of the hydration shells are responsible for the experimental trends.
B.04 Guest lecture
COBISS.SI-ID: 1537209539