Thermodynamic Modeling of Apparent Molal Volumes of Bivalent Metal Nitrate Salts with Pitzer Model

The apparent molal volumes of selected bivalent metal nitrate salts, Co(NO3)2, Ni(NO3)2, and Mg(NO3)2, in water have been assessed from the available density measurements of their aqueous solutions at 25 °C over a wide molality range. The values of have been fitted to the Pitzer model using its volumetric contributions. The model parameters , , and were determined for each aqueous electrolyte, over the composition range from 0 to about 4.5 mol·kg−1·H2O. The new experimental data and parameters obtained will be useful to extend the present database of electrolyte solutions and provide a reliable model for industrial use, which could be extended to other thermodynamic properties.