The data are entered in a series of fields, and options are set using radio buttons or check boxes.
Users should note that Model III is, for many compositions, only valid up to saturation with respect to the relevant inorganic solids. This applies particularly to solutions containing Na+ and Cl−, and Na+ and SO42−. However, for (NH4)2SO4 - H2SO4 - H2O mixtures the range of validity is much the same as for Model II, and the model parameterisations for NH4NO3 - H2O and NaNO3 -H2O also include data for supersaturated solutions and are thus valid to very high molalities.