Excess enthalpies of {2,2-dimethylbutane plus hexane plus (octane or dodecane)} at the temperature 298.15 K

Measurements of excess molar enthalpies at the temperature 298.15 K in a fl ow microcalorimeter are reported for the ternary mixtures {x(1)(CH3)(3)CCH2 CH3 + x(2)CH(3) (CH2)(4)CH3 + (1 - x(1) - x(2))CH3(CH2)(6)CH3} and {x(1)(CH 3)(3)CCH2CH3 + x(2)CH(3) (CH2)(4)CH3 + (1 - x(1) -x(2))CH3(CH2)(10)CH3}. Sm ooth representations of the results are described and used to construct con stant-enthalpy contours on Roozeboom diagrams. It is shown that useful esti mates of the ternary enthalpies can be obtained from the Flory theory using only the physical properties of the components and their binary mixtures. (C) 2000 Academic Press.