EXCESS MOLAR ENTHALPIES OF AN ALKANOL PLUS A CYCLIC ETHER AT 298.15 K

Excess molar enthalpies H-m(E) measured at 298.15 K using a flow calor imeter are reported for 12 mixtures of methanol, ethanol, propan-1-ol, or propan-2-ol + tetrahydrofuran (THF), + tetrahydropyran (THP), or 1,4-dioxane. For all of the systems investigated, H-m(E) is strongly positive over the whole mole fraction range and increases in the order methanol < ethanol < propan-1-ol < propan-2-ol. H-m(E) (maximum) depe nds on both the size of the cycloether ring and the number of carbon a toms in the alkanol molecule. The results are explained in terms of th e strong self-association exhibited by the alkanol and the cross-assoc iation of the O ... HO specific interaction.