Monoglyme-water mixtures

Figure 1. Plot of dielectric constant vs. mass percent monoglyme for 0,10, 30, 50, 70, 00, and 100 mass percent monoglyme-water mixtures at 298.15°K...

Figure 3. Plots of AG vs. 1/e at 298.15°K for hydrochloric acid and hydrobromic acid in monoglyme-water mixtures...

Thus hydrobromic acid is more strongly stabilized in monoglyme + water mixtures than in water. Moreover, the negative values of AG for the experimental mixed solvent compositions support the view that water is less basic than the mixed solvents, if it is assumed that the hydration of a larger bromide ion in aqueous solution is negligible, although our data indicates that the hydration number of chloride in aqueous solution might not be zero (22). 

Since anions are much less solvated in dipolar aprotic solvents (23) than in water, the hydrogen ion will be more highly solvated in the mixed solvent because it is preferentially solvated by monoglyme in the monoglyme-water mixtures rather than in the pure aqueous medium. The selective solvation is an important factor in an understanding of solute-solvent interactions in mixed solvent systems. Unfortunately, the detailed compositions of the primary solvation shell and the secondary mode of solvation (ion-dipole interaction) in mixed solvents are not yet clearly understood. 

Table VIII. Values of the Standard Potentials (on the Molal Scale) and the Corresponding Variations of the Ion-Size Parameter, a0, with the Standard Deviations of a(EIJl)/mV for x = 10, 30, and 50 Mass Percent Monoglyme—Water Mixtures at 298.15°K...

Monoglyme—Water Mixtures (x = Mass Percent Monoglyme)... 

Hydrochloric Acid in Monoglyme-Water Mixtures, Ph.D. Dissertation, Louisiana State University, 1966. 

The cobaltocenium system is of special interest, as in some solvents the second (reductive) process can be observed for Cc, and one can extract the experimental difference of two redox potentials dealing with only one model reactant. The redox potentials of the CcVCc/Cc couples were reported for usual aprotic solvents [12] and some specific low-dielectric solvents (namely monoglyme, dichloromethane, and diglyme) [19], as well as for water mixtures with these solvents [19, 20]. Corresponding water—solvent UP values were evaluated on the basis of these data, mostly finding themselves in the range of 0.2-0.3 V. In general UPs do not correlate with the solvent dielectric constant, but they are possibly affected by the hydrophylic or hydrophobic nature of the solvent. This result indicates indirectly the pronounced contribution of... 

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