Solvate inert component

The values of homomolecular association constants of alcohols and acids are high, typieally in the range of 10 -1 O. Therefore eoncentration of the eomponent A is rather low, even at high content of solvate-inert component B, and may be neglected. 

The relative degree of the decomposition of heteromolecular associates into aggregates of a smaller association degree increases with increased permittivity of the non-asso-ciated solvate-inert component. In solutions of equal concentration of the two mixed solvents, acetic acid-cyclohexane (8=1,88) and acetic acid-chlorobenzene (e=5,6), the relative degree of acid heteromolecular association is higher in the first system than in the second system. 

Selection of the second (indifferent) component s e also provides means to control the universal solvation ability of mixed solvent. In the above mentioned examples, increasing the solvate inert component concentration results in the decrease of mixed solvent 8. On the contrary, addition of indifferent component (propylene carbonate) into the systems such as acetic acid-propylene carbonate or propylene carbonate-aniline causes 8 to rise. Because in the last two systems acetic acid and aniline were chosen as solvate active components, it was obviously intended to use these mixtures for specific solvation of the dissolved donor and acceptor compounds respectively. 

In the special case of universal media, i. e., mixed solvent formed by both solvation-inert components, this equation can be presented as ... 

A) CCI4 - hepthylchloride formed by two solvate inert components [9.84]... 

B) CCI4 - nitromethane formed by solvate inert component (CCI4) and acceptor (nitromethane) component... 

A similar phenomenon is observed in conditionally-universal media A-B (A is solvate-active component, B is solvate-inert component). Association constant can be eal-culated from equations [9.56] or [9.104] for LiBr and KCNS solutions. ... 

The method for determination of average filling of molecules coordination sphere of dissolved substance by molecules of the mixed solvent (with one solvate-inert component) has been proposed. The local permittivity is related to average filling of molecules coordination sphere expressed by the equation ... 

Selection of the mixed solvent components allows us in most cases to provide controlled solvation of all substances, participating in the chemical process performed in solution. Often, it can be achieved by combination of solvate active and solvate inert components. For example, it is obvious that in all compositional range of mixture DMSO-CCI4 (except 100% CCI4) specific solvation of acid dissolved in this mixture is realized by DMSO. Similarly in mixed solvent formic acid-chlorobenzene, solvation of the dissolved donor substance is performed exclusively by formic acid. 

A similar phenomenon is observed in conditionally-universal media A-B (A is solvate-active component, B is solvate-inert component). Association constant can be calculated from equations [8.1.56] or [8.1.104] for LiBr and KCNS solutions. - The dependence of InK and l/e (Figure 8.1.16] for LiBr in mixed solvent [8.1.53] shows an influence of solvate-active component on K. The difference of LiBr solvation energy in the presence of pyridine and acetic acid may be evaluated in accordance to [8.1.53], assuming low solvation energy of Li" by propylene carbonate in comparison with pyridine and... 

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