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Air-water partitioning for 21 volatile chlorinated or brominated alkanes, alkenes, and aromatics was measured at 20°C by the inert gas stripping method. Results of the measurements are presented in the form of Henry's law constants (H 12 ), air-water partition coefficients (K aw ), and limiting activity coefficients (γ 1 ∞ ), accurate γ 1 ∞ values being obtained only if accurate pure solute vapor pressure data are available.The halocarbons studied in this work are hydrophobic and exhibit enhanced volatilities from their dilute aqueous solutions representing approximately ranges of γ 1 ∞ from 230 to 70 000 and H 12 from 2 to 70MPa. Correct performance of the stripping method for such systems requires special precautions. As confirmed by test measurements on benzene, chlorobenzene, 1,1,1-trichloroethane, and 1,1,2-trichloroethane, the complete equilibration in the stripping cell can be achieved under vigorous mixing of the cell, low stripping gas flow rates (approximately 10 cm 3 ‚min -1 ), and low relative elution rates (0.01 min -1 ). Choosing for each system a cell of a suitable volume made it possible to comply with the latter requirement. The results compare well with recent literature values obtained by various methods for some of the halocarbons. For two selected halocarbons (bromobenzene and 1,1-dichloroethane), detailed measurements of the temperature dependence of air-water partitioning were carried out in the range of (10-50)°C. These measurements corresponding to the range of H 12 from 5 to 72 MPa provide additional support for the validity of the method.

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Surface tensions of pure organic compounds and their dilute aqueous solutions (molar fraction typically x 2 < 0.015) at 298.15 K have been measured. The Szyszkowski equation has been used for correlation of the experimental surface tension data, and the ability of the equation to describe the concentration dependence of surface tension has been tested. When accurate values of surface tension were known, the Szyszkowski equation has been found to not be suitable for correlation, especially in the case when values of the first derivative, obtained from the parameters of a correlation equation, have been wanted. Therefore values of limiting slopes of surface pressure concentration dependence have been evaluated by a linear regression of the most dilute results (typically x 2 < 0.001).