An extended solvation theory for electrolyte osmotic and activity coefficients. Application to 1:1, 1:2, 1:3, 1:4, 2:1, 2:2, 3:1, 3:2 and 4:1 aqueous electrolyte solutions

In this work, we have used two models (DH-MS and PDH-MS) based upon the extended solvation theory to correlate osmotic and activity coefficients of electrolyte aqueous solutions. These models contain the long-range term of the Debye-Hückel (DH) theory or the Pitzer-Debye-Hückel (PDH) modification and a short-range term based upon a modified solvation (MS) theory. We have used literature experimental data of mean ionic activity and osmotic coefficients of 338 aqueous solutions. The electrolytes included in this work are type 1:1, 1:2, 1:3, 1:4, 2:1, 2:2, 3:1, 3:2, and 4:1 at 298.15 K. The results show that the DH-MS and PDH-MS models effectively correlate the experimental data within an average absolute percentage deviation of 0.588% and 0.688%, respectively. We have compared our results with those obtained from the Archer model. This model agrees within 0.769% with the literature data.