Excess molar enthalpies of binary mixtures of trichloroethylene with six 2-alkanols at 25 degrees C

Excess molar enthalpies H-E have been measured for the binary mixtures tric hloroethylene + 2-propanol, + 2-butanol, + 2-pentanol, + 2-hexanol, + 2-hep tanol, and + 2-octanol using an isothermal microcalorimeter at 25 degreesC. All the mixtures present exothermic events and showed minimum negative H-E values around 0.50-0.60 mole fraction of trichloroethylene. Minimum values of H-E vary from 450 J-mol(-1) up to 530 J-mol(-1) depending on the molecu lar weight of alkanol. The results are explained in terms of the strong sel f-association exhibited by the 2-alkanols and the formation of aggregates b etween unlike molecules through O . . . HO hydrogen bonding. The experiment al results for mixtures are well represented by the Redlich-Kister, NRTL, a nd Wilson equations, respectively.