Microcalorimetric measurements of excess molar enthalpies, measured at 298.
15 K, are reported for the ternary systems 2,2,4-trimethylpentane (1) + hex
ane (2) + octane (3) and 2,2,4-trimethylpentane (1) + hexane (2) + dodecane
(3). Smooth representations of the results are described and used to const
ruct constant-enthalpy contours on Roozeboom diagrams. It is shown that the
Flory theory provides a reasonable correlation of the results.