Henry’s law coefficient for

Table 8.3 Henry s Law coefficients for gases dissolved in water and benzene...

Tse, G., Orbey, H., Sandler, S. I. (1992) Infinite dilution activity coefficients and Henry s law coefficients for some priority water pollutants determined by a relative gas chromatographic method. Environ. Sci. Technol. 26, 2017-2022. 

Benkelberg, H.J., Hamm. S.. and Warneck, P. Henry s law coefficients for aqueous solutions of acetone, acetaldehyde and acetonitrile, and equilibrium constants for the addition compounds of acetone and acetaldehyde with bisulfite. /. Atmos. CAem.,20(l) 17-34,1995. 

Figure 20.7 Overall air-water transfer velocity vla/w as a function of Henry s Law coefficient for two very different wind conditions, 10 = 1 m s l (calm overland condition) and Kl0 = 20 m s 1 (rough ocean conditions). The solid lines are calculated for average compound properties Diz = 0.1 cm2 s 1 and Sc,w = 600. The dashed line indicates the boundary between air-phase- and water-phase-controlled transfer velocities. See Table 20.5 for definitions of parameters and substances.

Bonifacio, R.P., Padua, A. A.H., Costa Gomes, M.F. (2001) Perfluoroalkanes in water experimental Henry s law coefficients for hexafluoroethane and computer simulations for tetrafluoromethane and hexafluoroethane. J. Phys. Chem. B 105, 8403-8409. 

Some support for these qualitative ideas comes from an extra-thermodynamic analysis of solubilities in liquid mixtures. Krishchevsky (O Connell 1971) showed that if the mixture is ideal then the Henry s law coefficient for a solute in the mixture, L3 (1, 2), is related to the Henry s law coefficients for the solute in the two pure components, L3 (1) and L3 (2) by eqn (34)... 

Henry s law coefficients and effective Henry s law coefficients for gases of concern in cloud chemistry are summarized in Figure 3. 

Figure 3. pH-Dependence of the effective Henry s law coefficient for gases which undergo rapid acid-base dissociation reactions in aqueous solution, as a function of solution pH, Buffer capacity of solution is assumed to greatly exceed incremental concentration from uptake of indicated gas. Also indicated at the right of the figure are Henry s law coefficients for non-dissociative gases. For references see (28). 

The quantities in brackets represent activies of ions in solution and of components in the solid phase. Application of the defining equation directly would require knowing activity coefficients for the ions in solution and also the Henry s law coefficient for the trace carbonate in solid solution. A practical approach is to rewrite equation (13) in terms of an effective or empirical distribution coefficient... 

Table 8-2. Henry s Law Coefficients for Several Atmospheric Gases, In-Cloud Scavenging Efficiencies eg, Concentrations cs of Dissolved Substances in Cloud Water for Initial Gas-Phase Mixing Ratios m0, and Residence Times t for Rainout"... 

Table 7.2 gives the Henry s law coefficients for some atmospheric gases in liquid water at 298 K. The values given reflect only the physical solubility of the gas, that is, only the equilibrium (7.2) regardless of the subsequent fate of A once dissolved. Several of the species given in Table 7.2, once dissolved, either undergo acid-base equilibria or react with water. We will consider the effect of these further processes shortly. A detailed compilation of Henry s law coefficients for species important in environmental chemistry can be found in Sander (1999). 

Note that liquid water concentration has already been incorporated into the hydrolysis constant and that Khc is identical to the Henry s law coefficient for carbon dioxide, Wco2-... 

The effective Henry s law constant for S02 increases by almost seven orders of magnitude as the pH increases from 1 to 8 (Figure 7.6). The effect of the acid-base equilibria is to pull more material into solution than predicted on the basis of Henry s law alone. The Henry s law coefficient for S02 alone, HSOl, is 1.23 M atm"1 at 298 K, while for the same... 

So under atmospheric conditions practically all dissolved ammonia in clouds is in the form of ammonium ion. The aqueous-phase concentrations of [NH ] in equilibrium with 1 ppb of NH3(g) are shown in Figure 7.9. The partitioning of ammonia between the gas and aqueous phases inside a cloud can be calculated using (7.9) and the effective Henry s law coefficient for ammonia, // = Wnh, Ka [H+]/ATm. If the cloud pH is less than 5 practically all the available ammonia will be dissolved in cloudwater (Figure 7.10). 

Formaldehyde has a Henry s law constant Hhcho = 2.5 M atm-1 at 298 K (Betterton and Hoffmann 1988), but its water solubility is enhanced by several orders of magnitude as a result of the diol formation. Combining the Henry s law equilibrium and the hydrolysis relationships, we can calculate the effective Henry s law coefficient for the total dissolved formaldehyde //((CHO as... 

TABLE 19.5 Correction Factors for Henry s Law Coefficients for Species that Dissociate on Absorption... 

Table 6.2 gives the Henry s law coefficients for some atmospheric gases in liquid water at 298 K. The values given reflect only the physical solubility of the gas, that is, only the... 

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