Non-Electrolyte Solutions

Sulfamide, (H2N)2S02, can be made by ammonolysis of SO3 or O2SCI2. It is a colourless crystalline material, mp 93°, which begins to decompose above this temperature. It is soluble in water to give a neutral non-electrolytic solution but in boiling water it decomposes to ammonia and sulfuric acid. The structure (Fig. 15.50c)... 

Activity coefficient models offer an alternative approach to equations of state for the calculation of fugacities in liquid solutions (Prausnitz ct al. 1986 Tas-sios, 1993). These models are also mechanistic and contain adjustable parameters to enhance their correlational ability. The parameters are estimated by matching the thermodynamic model to available equilibrium data. In this chapter, vve consider the estimation of parameters in activity coefficient models for electrolyte and non-electrolyte solutions. 

Williamson,. G., "An Introduction to Non-Electrolyte Solutions", John Wiley and Sons, New York (1967). 

A compilation of various thermodynamic and transport properties, including aqueous electrolyte and non-electrolyte solutions... 

Nemst distribution law for regular mixtures and solvents ) it The non-electrolyte solute A in water A... 

Van Ness, H. C., Classical Thermodynamics of Non-Electrolyte Solutions, Pergamon... 

Maron, S. H., Nakajima, N. A theory of the thermodynamic behavior of non electrolyte solutions. II. Application to the system benzene-rubber. J. Polymer Sci. 40, 59-71... 

Scatchard, G. 1931. Equilibria in non-electrolyte solutions in relation to the vapor pressures and densities of the componentsChem. Rev8 321-333. 

The solubility parameter 8 of Hildebrand [14] as defined in equation (1.31), can often be used in estimating the solubility of non-electrolytes solutes in organic solvents. 

Manufacture of bacterial cellulose with desired shape Development of Kedem-Katchalsky equations of the transmembrane transport for binary nonhomogeneous non-electrolyte solutions Honeycomb patterned bacterial cellulose... 

Tab. 4.14 Permeability coefficients (Pm) for various non-electrolyte solutes across egg lecithin bilayer membranes at 25 °C. (Reprinted from Tab. 2 of ref. 49 with permission from Bertels-mann-Springer)...

Prausnitz, J. M. Molecular Thermodynamics of Fluid-Phase Equilibria Prentice Hall Englewood Clifls, NJ, 1969 Chapter 7. Aeree, W. E., Jr., W. E. Thermodynamic Properties of Non-Electrolyte Solutions Academic Press New York, 1984 Chapter 8. 

A. G. Williamson, An Introduction to Non-Electrolyte Solutions, Oliver and Boyd, London, 1967. 

Despite the noted problems, the work of Bonner, Bunzl and Woolsey162 suggests that the extent of disruption of the structure of solvent NMA by added nonelectrolytes is markedly dependent on the solute. Certain solutes which can act as electron acceptors (e.g., anthraquinone162 and 4,4 -dinitrodibenzyl172 ) are found to show deviations from Raoult s law which are considerably less positive than deviations found for most non-electrolyte solutions in NMA. 

The solubility of a dissolved non-electrolyte solute can be reduced by the addition of a salt. This phenomenon, known as the salting-out effect, is of practical importance for the isolation of organic compounds from their solutions. In the presence of a dissolved dissociated salt, a fraction of the solvent molecules becomes involved in solva-tional interaction with the ions of the electrolyte, whereby their activity is diminished, leading to salting-out of the dissolved non-electrolyte solute. In other words, the salting-out can be considered as the difference in solubility in two kinds of solvents, the ion-free and the ion-containing one [248]. 

The square root of the cohesive pressure c as defined in Eq. (3-5) has been termed the solubility parameter 8 by Hildebrand and Scott [98] because of its value in correlating and predicting the solvency of solvents for non-electrolyte solutes [cf. Eqs. (2-1) and (5-77) in Sections 2.1 and 5.4.2, respectively]. Solvency is defined as the ability of solvents to dissolve a compound [118]. A selection of 8 values is given in Table 3-3 see also references [99, 177]. 

Thermodynamically available fraction (TAF). Early studies of the influence of non-electrolyte solutes on aqaatic organisms identified two kinds of toxicity - physical toxicity (or narcosis) and chemical toxicity (12). Narcosis 4-s caused by a wide variety of substances (including the atmospheric gases) and seems to arise because essential pathways are physically blocked by an excess of inert molecules that have entered the organisip via an equilibrium distribution across an outer membrane. At equilibrium the activities of the toxic compound are the same in the organic phase and in the aqueous phase. Consequently, the thermodynamic... 

As regards aqueous solutions of electrolytes, there has been some significant advance in the understanding of the dielectric behaviour of the hydration sheath around the ions. In the field of non-electrolyte solutions, no claim can yet be made that th e is good understanding. It is obvious that the data are still insufficient this is the fidd where measurements are most needed. 

Much of the high-frequency work that has been done on aqueous non-electrolyte solutions has yielded data at too few frequencies for an analysis of them to be free from ambiguity. It is to be hoped that the new time-domain techniques will remedy this deficiency. 

Hagen-Poiseuille law, 72 Hagenbach coefficient, 74 correction, 73, 75 hanging drop, 183, 189 level viscometer, 80 Hare s apparatus, 12 Harkins s equation, 155 heat capacity of electrolyte solution, 225 content of electrolyte and non-electrolyte solutions, 225-6 content of vapour, 348 Heilborn s specific heat formula, 218 Henning s latent heat formula, 307 Herwig s method for density of saturated vapour, 325... 

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