Abstract
The molar excess enthalpies of mixing for the six possible binary combinationsof solutions of NaCl, KCl, NaBr, and KBr as a function of ionic strength fractionhave been measured at 25°C. The experiments were performed at constant ionicstrengths of 1.000 and 2.000 mol-kg−1 with an LKB flow microcalorimeter inthe mixed solvent water + dimethylformamide. The equations of Friedman'sModel were fitted to the results. Our parameters differ appreciably from thecorresponding results in water and Young's cross square rule does not apply.While Pitzer's ion-interaction model was able to represent the enthalpy data forcommon ion mixings, it was unable to model the data of the noncommon ionmixtures. The data suggests that the problem may arise from variations in solvationof the ions and ion clusters including preferential solvation of certain species.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
REFERENCES
K. S. Pitzer, J. Phys. Chem. 77, 268 (1973).
K. S. Pitzer, in Activity Coefficients in Electrolyte Solutions (CRC Press, Boca Raton, FL, 1979), p 157.
C. E. Harvey and J. H. Weare, Geochim. Cosmochim. Acta 44, 981 (1980).
R. T. Pabalon and K. S. Pitzer, Geochim. Cosmochim. Acta 51, 2429 (1987).
T. F. Young, Rec. Chem. Progr. 12, 81 (1951).
A. A. Krawetz, Discussions Faraday Soc. 24, 77 (1957).
C. J. F. Bottcher, Discussions Faraday Soc. 24, 78 (1957).
R. H. Wood and R. W. Smith, J. Phys. Chem. 69, 2974 (1965).
Y. C. Wu, M. B. Smith, and T. F. Young, J. Phys. Chem. 69, 1868 (1965).
Y. C. Wu, M. B. Smith, and T. F. Young, J. Phys. Chem. 69, 1873 (1965).
P. P. Singh and Bal Raj, Thermochim. Acta 230, 113 (1993)
A. J. Ellis and I. M. Mcfadden, Geochim. Cosmochim. Acta 30, 413 (1972)
F. J. Millero, Pure Appl. Chem. 57, 1015 (1985).
D. J. Turner, in Thermodynamics of Aqueous Systems with Industrial Applications, S. A. Newman ed. (Am. Chem. Soc., Washington, D. C., 1980), p. 653.
A. M. Rowe and J. C. S. Chou, J. Chem. Eng. Data 15, 61 (1970).
A. Vogel, A textbook of Practical Organic Chemistry, 4th edn. (ELBS and Longman, London, 1978), p 277.
Y. Marcus, Ion Solvation (Wiley, Chichester, 1985), p. 306.
H. S. Harned and B. B. Owen, Physical Chemistry of Electrolytic Solutions (Reinhold, New York, 1966), p. 713.
E. G. Paneda, C. Yanes, J. J. Calvents, and A. Maestre, J. Chem. Soc. Faraday Trans. 90, 575 (1994).
M. Woldan, Z. Phys. Chem. 150, 201 (1986).
P. Monk and Z. Wadsö, Acta Chem. Scand. 22, 1844 (1968).
R. H. Stokes, K. N. Marsh, and R. P. Tomlins, J. Chem. Thermodyn. 1, 211 (1969).
H. L. Friedman, J. Chem. Phys. 32, 1134 (1960).
H. L. Friedman, Ionic Solution Theory (Interscience, New York, 1962).
H. L. Friedman and P. S. Ramanathan, J. Phys. Chem. 74, 3756 (1970).
R. C. Phutela and K. S. Pitzer, J. Solution Chem. 15, 649 (1986).
T. F. Young and M. B. Smith, J. Phys. Chem. 58, 716 (1954).
T. F. Young, W. C. Wu, and A. A. Krawetz, Discussions Faraday Soc. 24, 37 (1957).
H. L. Friedman and C. V. Krishanan, in Water—A Comprehensive Treatise, Vol. 3, F. Franks ed. (Plenum Press, New York, 1973), p.1.
Y. Marcus, J. Solution Chem. 13, 599 (1984).
O. Y. Samoilov, Structure of Electrolytic Solutions and the Hydration of Ions (English Transl., Consultants Bureau, New York, 1965).
A. D. Covington and A. K. Covington, J. Chem. Soc. Faraday Trans. Part I 71, 831 (1975).
Y. Marcus, Pure Appl. Chem. 62, 2069 (1990).
Y. Marcus, J. Phys. Chem. 91, 4422 (1987).
Y. Marcus, J. Phys. Chem. 92, 3613 (1988).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Deshwal, B.R., Singh, K.C. & Schreiber, D.R. Thermodynamics of 1:1 Electrolyte Solutions in Water + N,N-Dimethylformamide Mixed Solvent System at 25°C: Molar Excess Enthalpy of Mixing. Journal of Solution Chemistry 29, 561–574 (2000). https://doi.org/10.1023/A:1005146213854
Issue Date:
DOI: https://doi.org/10.1023/A:1005146213854