Temperature and concentration dependences of the electrical conductance, diffuson and kinetic parameters of sodium selenite solutions in ordinary and heavy water

摘要

On the basis of conductometric measurements, empirical equations were derived that describe the temperature and concentration dependences of the electrical conductance of Na2SeO3 solutions in ordinary and heavy water. The values of the equivalent conductance of the ions at infinite dilution were determined in the temperature region 12 to 45 degrees C, as well as the kinetic parameters for ionic motion in the solutions. These parameters were compared with respect to the solvent nature. The values of the effective ionic radii and ionic hydration numbers were obtained. The changes of Gibbs energy, entropy and enthalpy for the transition of ions from one quasi-equilibrium state to another were calculated at different temperatures. According to the terms of Samoylov's theory, Na+ and SeO2/(-)(3) ions in H2O and D2O were shown to be positively hydrated and stabilize the solvent structure, with this effect being more pronounced in D2O and increasing slightly with increasing temperature.