Abstract
Isopiestic vapor-pressure measurements were made at the temperature 298.15 K for aqueous KCl + MgCl2 solutions using KCl(aq) as the reference standard. The measurements for these ternary solutions were made at KCl ionic strength fractions of y=0.0, 0.1989, 0.3996, 0.5993, 0.7925 and 1.0 (with two additional sets at y=0.0, 0.2021, 0.3998, 0.6125, 0.8209 and 1.0) for the ionic strength range from 0.4014 to 6.2790 mol⋅kg−1. Our results, and those from two previous isopiestic studies, were combined and used with previously determined parameters for KCl(aq) and those determined here for MgCl2(aq) to evaluate mixing parameters for the Clegg-Pitzer-Brimblecombe model. These combined data were also used to determine the mixing parameters of the Scatchard model. Both sets of model parameters are valid for ionic strengths of I≤12.8 mol⋅kg−1, where higher-order electrostatic effects have been included in the Clegg-Pitzer-Brimblecombe mixture model. The activity coefficients for KCl and MgCl2 were calculated from these models and the results for KCl were compared to experimental data from Emf measurements. The Scatchard model interaction parameters were used for calculation of the excess Gibbs energy as a function of the ionic strength and ionic strength fraction of KCl. The Zdanovskii-Robinson-Stokes rule of linearity for mixing of isopiestic solutions was tested.
We’re sorry, something doesn't seem to be working properly.
Please try refreshing the page. If that doesn't work, please contact support so we can address the problem.
References
Robinson, R.A., Stokes, R.H.: A thermodynamic study of bivalent metal halides in aqueous solution. Part XV. Double chlorides of uni- and bivalent metals. Trans. Faraday Soc. 41, 752–756 (1945)
Kirginstev, A.N., Lukyanov, A.V.: Investigation of three component solutions by the isopiestic method VII. Three component solutions LiCl-CsCl-H2O, KCl-CsCl-H2O, RbCl-CsCl-H2O, KCl-CaCl2-H2O, KCl-MgCl2-H2O. Zh. Fiz. Chim. 40, 1280–1284 (1966)
Padova, J., Saad, D.: Thermodynamics of mixed electrolyte solutions. VIII. An isopiestic study of the ternary system KCl-MgCl2-H2O at 25 °C. J. Solution Chem. 6, 57–71 (1977)
Kuschel, F., Seidel, J.: Osmotic and activity coefficients of aqueous K2SO4-MgSO4 and KCl-MgCl2 at 25 °C. J. Chem. Eng. Data 30, 440–445 (1985)
Christenson, P.G., Gieskes, J.M.: Activity coefficients of KCl in several mixed electrolyte solutions at 25 °C. J. Chem. Eng. Data 16, 398–400 (1971)
Pavićević, V., Ninković, R., Todorović, M., Miladinović, J.: Osmotic and activity coefficients of {yNaH2PO4+(1−y)Na2SO4}(aq) at the temperature 298.15 K. Fluid Phase Equilib. 164, 275–284 (1999)
Archer, D.G.: Thermodynamic properties of the KCl + H2O system. J. Phys. Chem. Ref. Data 28, 1–17 (1999)
Pitzer, K.S., Wang, P., Rard, J.A., Clegg, S.L.: Thermodynamics of electrolytes. 13. Ionic strength dependence of higher-order terms; Equations for CaCl2 and MgCl2. J. Solution Chem. 28, 266–282 (1999)
Zdanovskii, A.B.: Functional relation of the properties of the mixed and individual solutions. Tr. Solyanoi Lab. Vses. Inst. Galurgii Akad. Nauk SSSR 2, 70 (1936)
Stokes, R.H., Robinson, R.A.: Interactions in aqueous nonelectrolyte solutions. I. Solute-solvent equilibrium. J. Phys. Chem. 70, 2126–2131 (1966)
Chen, H., Sangster, J., Teng, T.T., Lenzi, F.: A general method of predicting the water activity of ternary aqueous solutions from binary data. Can. J. Chem. Eng. 51, 234–241 (1973)
Clegg, S.L., Pitzer, K.S., Brimblecombe, P.: Thermodynamics of multicomponent, miscible, ionic solutions. 2. Mixtures including unsymmetrical electrolytes. J. Phys. Chem. 96, 9470–9479 (1992)
Clegg, S.L., Pitzer, K.S.: Thermodynamics of multicomponent, miscible, ionic solutions: generalized equations for symmetrical electrolytes. J. Phys. Chem. 96, 3513–3520 (1992)
Goldberg, R.N., Nuttall, R.L.: Evaluated activity and osmotic coefficients for aqueous solutions: The alkaline earth metal halides. J. Phys. Chem. Ref. Data 7, 263–310 (1978)
Rard, J.A., Miller, D.G.: Isopiestic determination of the osmotic and activity coefficients of aqueous MgCl2 solutions at 25 °C. J. Chem. Eng. Data 26, 38–43 (1981)
Stokes, R.H.: A thermodynamic study of bivalent metal halides in aqueous solution. Part XIV. Concentrated solutions of magnesium chloride at 25 °C. Trans. Faraday Soc. 41, 642–645 (1945)
Gibbard, H.F., Gossmann, A.F.: Freezing points of electrolyte mixtures. I. Mixtures of sodium chloride and magnesium chloride in water. J. Solution Chem. 3, 385–393 (1974)
Scatchard, G.: Osmotic coefficients and activity coefficients in mixed electrolyte solutions. J. Am. Chem. Soc. 83, 2636–2642 (1961)
Pitzer, K.S.: Thermodynamics of electrolytes. V. Effects of higher-order electrostatic terms. J. Solution Chem. 4, 249–265 (1975)
Author information
Authors and Affiliations
Corresponding author
Additional information
An erratum to this article can be found at http://dx.doi.org/10.1007/s10953-011-9707-1
Rights and permissions
About this article
Cite this article
Miladinović, J., Ninković, R. & Todorović, M. Osmotic and Activity Coefficients of {yKCl+(1−y)MgCl2}(aq) at T=298.15 K. J Solution Chem 36, 1401–1419 (2007). https://doi.org/10.1007/s10953-007-9197-3
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10953-007-9197-3