Calculation of the osmotic and activity coefficients of seawater at 25°C

Journal of Solution Chemistry - Tập 1 - Trang 481-488 - 1972
R. A. Robinson1, R. H. Wood2
1Department of Chemistry, University of Florida, Gainesville
2Department of Chemistry, University of Delaware, Newark

Tóm tắt

The equation of Reilly, Wood, and Robinson was used to predict the osmotic coefficient of seawater and of its concentrates at molal ionic strengths of 0.5 to 6.0 at 25°C. The results agree closely with experimental data at ionic strengths below 5. The average difference in osmotic coefficients over the entire concentration range is 0.0014. The only serious discrepancy is at an ionic strength of 6, where a difference of 0.0068 is found. The accuracy of the predictions of osmotic coefficients prompted the calculation of the activity coefficients of NaCl, Na2SO4, MgCl2, MgSO4, KCl, and K2SO4 in the mixture. The calculated activity coefficients of NaCl and Na2SO4 agree within experimental error with previous measurements. This agreement demonstrates the prediction of activity and osmotic coefficients for complex mixtures.

Tài liệu tham khảo

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