A new g(E) model describing the behaviour of single and mixed solvent electrolyte systems is used to calculate vapour-liquid equilibria of 185 ternary systems (two solvents one salt), and vapour pressure, osmotic coefficients and activity coefficients of 362 binary systems (one solvent one salt). The results are compared with the models of Sander, Macedo, Pitzer, Bromley and Chen. For the large data base used, the new model improves the results not only for the description of single solvent data but also for the calculation of VLE for mixed solvent systems. Despite the relative improvement compared to other models, in certain cases serious deviations are obtained.