ACTIVITIES AND THERMODYNAMIC EXCESS PROPERTIES OF AQUEOUS 2,5-DIMETHYLPYRIDINE MIXTURES NEAR THE CRITICAL DEMIXING POINT - COMPARISON WITH 2,6-DIMETHYLPYRIDINE WATER MIXTURES

摘要

Activities of 2,5-dimethylpyridine in aqueous solution have been measured at eleven temperatures, two below and nine above the lower critical temperature of the mixture, by the dynamic method of Randall and Weber. Gibbs free energy, enthalpy and entropy are derived to obtain excess quantities and all the results are discussed in connection with the liquid-liquid phase separation, the critical situation and the association properties of the molecules. A comparison is also made with the aqueous 2,6-dimethylpyridine system. A new version of the phase diagram is proposed. [References: 37]