Excess enthalpies and excess heat capacities of binary mixtures of (cyclohexanone, or 2-butanone, or 1,4-dioxane+1,2-dimethoxyethane) and (1,4-dioxane+1,2-dimethoxyethane) at T=298.15 K

Excess enthalpies and excess heat capacities of {x2-butanone + (1 - x)1,4-dioxane}, and {xeyclohexanone, or 2-butanone, or 1,4-dioxane + (1 - x)1,2-dimethoxyethane} were measured at T = 298.15 K. Excess enthalpies were negative for {x2-butanone + (1 - x)1,2-dimethoxyethane), and negative with a small positive part in the region of x > 0.8 for {xcyclohexanone + (1 - x)1,2-dimethoxyethane}, whereas excess enthalpies of {x2-butanone +(1 - x)1,4-dioxane} were positive as for {xcyclohexanone + (1 -x)1,4-dioxane} previously reported. Excess enthalpies of {x1,4-dioxane + (1 - x)1,2-dimethoxyethane} were positive. The results were compared with the systems reported earlier. Excess heat capacities are positive for {x2-butanone + (1 - x) 1,2-dimethoxyethane} and {xcyclohexanone + (1 - x)1,2-dimethoxyethane}, and negative for {x2-butanone + (1 - x) 1,4-dioxanel and {x1,4-dioxane + (1 - x) 1,2-dimethoxyethane}. The last mixture shows a W-shaped curve of excess heat capacity. (C) 2001 Academic Press.