Solubility of volatile electrolytes

Clegg, S.L. and Brimblecombe, R (1990) Solubility of volatile electrolytes in multi-component solutions with atmospheric applications. In Chemical Modelling in Aqueous Systems II (eds Melchior, D.C. and Bassett, R.L.). American Chemical Society, Washington, DC. 

Solubility of Volatile Electrolytes in Multicomponent Solutions with Atmospheric... 

On the Solubility of Volatile Weak Electrolytes in Aqueous Solutions... 

Maurer G. On the solubility of volatile weak electrolytes in aqueous solutions. ACS Symp Ser 1980 133 139-172. 

SOLUBILITY OF A WEAK ELECTROLYTE IN SALT SOLUTIONS. Calculation of the solubility of a volatile strong electrolyte, such as HCl, in aqueous salt solutions is straightforward. However, solubilities of weak electrolytes are more difficult to model accurately, since the dissolved speciation must frequently be determined in addition to the activity of the component of interest. Thus, in the case of NH3, the relevant ionic interactions involving NH4 and OH" must be known in addition to parameters for the interaction of dissolved salts with the neutral NH3 molecule. See, for example, the work of Maeda et al. (47) on the dissociation of NH3 in LiCl solutions. 

This work and others (5, 51) have shown how the Pitzer model, together with appropriate Henry s law constants, can be used to calculate the solubility of volatile strong electrolytes in multicomponent solutions. The treatment of NH3 summarized above shows that Pitzer formalism can also be used to describe the solubility of weak and non-electrolytes. We have noted how, for low concentrations of NH3, the Pitzer equations reduce to a series of binary interaction terms similar in form to those of the well known Setchenow equations. However, the thermodynamically based approach constitutes a significant improvement over the use of purely empirical equations to predict individual thermodynamic properties because it is equally applicable to both electrolytes and uncharged species, and provides a unified description of a number of important solution properties. 

From G. Maurer, "On the Solubility of Volatile Weak Electrolytes In Aqueous Solutions", Thermodynamics of Aqueous Syatema with Industrial... 

Maurer, G., "On the Solubility of Volatile Weak Electrolytes in Aqueous Solutions", Thermodynamics of Aqueous Systems with Industrial Applications. S.A. Newman, ed., ACS Symposium Series 133, Washington D.C.. ppl39-172 (1980)... 

Now interpret phase X as pure solute then Cs and co become the equilibrium solubilities of the solute in solvents S and 0, respectively, and we can apply Eq. (8-58). Again the concentrations should be in the dilute range, but nonideality is not a great problem for nonelectrolytes. For volatile solutes vapor pressure measurements are suitable for this type of determination, and for electrolytes electrode potentials can be used. 

Gtickel, W., Kastel, R., Lawerenz, J., Synnatschke, G. (1982) A method for determining the volatility of active ingredients used in plant protection. Part III The temperature relationship between vapour pressure and evaporation rate. Pestic. Sci. 13,161-168. Hafkenscheid, T. L., Tomlinson, E. (1981) Estimation of aqueous solubilities of organic non-electrolytes using liquid chromatographic retention data. J. Chromatogr. 218, 409 -25. 

Soluble substances fall into two classes those that give solutions which do not conduct electricity, called non-electrolytes and those that give solutions that do conduct electricity, called electrolytes. In solution non-electrolytes behave normally, or in other words, molecular weight methods show the same number of moles that one would expect to find in the gaseous state of that substance if it were volatile. Electrolytes, on the other hand, show a greater number of moles than one would normally expect to find. 

COMPARISON OF SALT EFFECTS. In order to illustrate the effect of dissolved salts on the solubility of both volatile strong electrolytes and neutral species, conditional Henry s law constants Kh, K h are defined for the two solute types such that ... 

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