SURFACE-TENSION OF LIQUIDS FROM MOLTEN NITRATE MIXTURES TO WATER

For a long time, progress in the studies of molten salt chemistry and aqueous solution chemistry was made almost independently. Recently, salt-water systems were investigated from molten salts to water, to bridge the gap between these two fields of research, particularly concerning thermodynamic and transport properties. Another property of considerable importance to arriving at structural information on salt-water systems is the surface tension which has never been studied over the whole concentration range. Therefore, as a new step, this paper reports the results on surface tension measurements of some AgNO3-TlNO3-H2O and AgNO3-TlNO3-M(NO3)n-H2O systems with M = Cs, Cd, and Ca, with regard to the influence of both the water mole fraction and the temperature. By applying the Guggenheim and Adam method and the Butler equation, reasonable orders of magnitude for the values of the water mole fraction, activity, and activity coefficient in the surface phase were obtained. Moreover, it was found that the free energy of hole formation in the Furth theory of liquids is close to the free energy of activation for the viscous now in the Eyring equation. This result suggests that holes may be considered as fundamental structural entities in the chemistry of all solutions from molten salts to water.