Excess molar enthalpies of binary mixtures containing N,N-dimethylformamide plus six 2-alkanols (C-3-C-8) at 300.15 K

Excess molar enthalpies, H-m(E), of N,N-dimethylformamide + 2-propanol, + 2 -butanol, + 2-pentanol, + 2-hexanol, + 2-heptanol, and + 2-octanol have bee n determined at 300.15 K and atmospheric pressure using an isothermal micro calorimeter. H-m(E) values are positive over the entire range of compositio n of N,N-dimethylformamide and increase in the order 2-propanol < 2- butano l < 2-pentanol < 2-hexanol < 2-heptanol < 2-octanol. Maximum values of H-m( E) vary from 500 J.mol(-l) up to 900 J.mol(-l). The results are explained i n terms of the strong self-association exhibited by the 2-alkanols and the cross-association of the O . . . HO specific interaction. The Redlich-Kiste r equation, fitted to the experimental results, provides a satisfactory mat hematical representation of H-m(E) in all mixtures.