Heat capacities and volumes of the ternary system benzene-water-2-propanol

Abstract

The densities and heat capacities per unit volume were measured over the whole miscibility region of the ternary system benzene-2-propanol-water. From these data, the apparent molal volumes and heat capacities of benzene and water were calculated. These functions for benzene show large changes in the water-rich region while the functions for water change rapidly in the benzene-rich region. In the intermediate range all changes are gradual. These results suggest that microtransitions, which are analogous to the formation of micelles and inverse micelles, occur in the two extremes of the phase diagram, and in that this system behaves similarly to a microemulsion. The absence of sudden changes in the thermodynamic functions in the intermediate region is consistent with a bicontinuous model for microemulsions.

Ultrasonic velocity, excess adiabatic compressibility, apparent molar volume, and apparent molar compressibility properties of binary liquid mixtures containing 2-butoxyethanol

“…A denser packing of the molecules results in an increase in the ultrasonic velocity and a decrease in the compressibility of these solutions. This 3~h e supplementary tables may be purchased from (2) in mixtures of ( A ) W-BE (2), (B) BE-BNZ (2), and (C) BE-DEC (2) …”

“…It has been shown that microphase structures occur in mixtures of water, alcohol, and oil (1)(2)(3). Water and alcohol mixtures themselves show unique minima and maxima in their thermodynamic properties at low alcohol concentrations (4)(5)(6)(7)(8)(9)(10).…”

“…The formation of such structures also are apparent in mixtures of water and other organic solvents (11)(12)(13)(14)(15)(16)(17)(18). It has been observed that the addition of a hydrocarbon component changes the "clathratelike" structures of the binary water-alcohol systems and gives rise to stable microphase structures (1)(2)(3). For example, surfactants have been found to have a large stabilizing effect on these microphase structures and they give rise to the formation of microemulsions and emulsions of relatively larger size (19).…”

Rôle de l'alcool dans les microemulsions. II. Volumes et capacités calorifiques molaires apparents du système eau + dodécylsulfate de sodium + isopropanol à 298,15 K

“…La nature de l'isopropanol, de par son caractere Itgerernent amphiphile, fait qu'il est susceptible de former des microagrCgats dans l'eau, aussi certains auteurs ont-ils CvoquC le "r61e actif de l'isopropanol dans les micro6mulsions sans detergent" (33,34). Dans les solutions micellaires, l'isopropanol agit a la fois sur la structure du solvant ct sur les proprietts micellaires provoquant un abaissernent de la cmc du tensioactif.…”

Volumes and heat capacities of transfer of ammonium salts from water to aqueous octyldimethylamine oxide at 25 °C

“…Incidentally, in recent years, the amount of reliable data on such functions has increased remarkably (9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22). At the same time, theoretical models have been developed to simulate the trends in the transfer functions and extract, from the data, fundamental thermodynamic parameters for the mixed micelles (18)(19)(20)(21)(22)(23)(24)(25)(26)(27).…”