Volumetric properties of acetonitrile with 1,2-alkanediols (C-2-C-6) at 20degrees C

Dilatometric measurements of excess molar volumes. V-E and excess partial m olar volumes, (V) over bar (E)(i) have been made for binary mixtures of ace tonitrile with 1,2-ethanediol, 1,2-propanediol, 1,2-butanediol, 1,2-pentane diol, and 1,2-hexanediol at 20 degreesC over the entire composition range. V-E for acetonitrile + 1,2-ethanediol and 1,2-propanediol mixtures are nega tive over the entire range of mole fractions and positive values are obtain ed for all remaining mixtures. The results are explained in terms of dissoc iation of the self-associated 1,2-alkanediol molecules and the formation of aggregates between unlike molecules through O-H . . .N-C hydrogen bonding. From the experimental results. VF were calculated and correlated by Redlic h-Kister type function in terms of mole fractions. The excess partial molar volumes were extrapolated to zero concentration to obtain the limiting val ues at infinite dilution, (V) over bar (/E,o)(i).