I.S. Lugina, D.A. Tanasjuk, V.I. Ermakov

Data is obtained specific electric conductivity (EC) dependences on concentration and temperature for the big group of water solutions are investigated. It is shown that in the (0,001÷1) M range of concentration EC isotherms are slightly convex curves increasing with concentration and in many cases appear to be not smooth but containing a number of breaks, coinciding with changes in solutions structure. Approximation of these isotherms by straight line equation χ = aсC + bc reveals three groups of the electrolytes characterized by various dependence aс on Gibbs energy ΔG: 1-1 type electrolytes, 2-1 type and 2-2. Free member bc is interpreted as own solvent conductivity. The analysis both corresponding correlations of isotherms and isoconcentrates EC shows the existence of two EC mechanisms in solutions: ionic and electron-hole. EC activation energy dependence on solution concentration is represented by curves with considerable "emissions" of experimental points coinciding with Mishchenko points (ТМ). At ТМ non-ionic contribution to EC exceeds the contribution of ionic component. It is shown that individual leap length of ions L is less than their own size, hence ions do not move together with their hydration shell, and its motion is oscillative. At solution freezing point ion fluctuation in the enclosed electric field becomes impossible and EC is about to disappear.