Excess molar volumes V-m(E) of (di-n-butyl ether (DBE) + a monofunctional organic compound) have been determined at T = 298.15 K over the whole composition range by means of a vibrating-tube densimeter. The V-m(E) values were either positive (propylamine, or butylamine, or acetone, or tetrahydrofuran + DBE) or negative (methanol, or butanol, or diethyl ether, or cyclopentanone, or acetonitrile + DBE). Markedly asymmetric V-m(E) curves were displayed by (DBE + methanol) and (DBE + acetonitrile). Partial molar volumes (V) over bar (0)(m) at infinite dilution in DBE, both from this work and the literature, were analysed in terms of an additivity scheme, and the group contributions thus obtained were discussed and compared with analogous results in water. DBE revealed a greater capability of distinguishing between polar and non-polar solutes, as well as in discriminating differently shaped molecules (unbranched, branched, cyclic). The limiting slopes of apparent excess molar volumes are evaluated and briefly discussed in terms of solute-solute and solute-solvent interactions. (C) 2001 Academic Press.
Volumetric properties of (an organic compound plus di-n-butyl ether) at T=298.15 K
BERNAZZANI, LUCA;CECCANTI, NORBERTO;CONTI, GIOVANNI;MOLLICA, VINCENZO;TINE', MARIA ROSARIA;
2001-01-01
Abstract
Excess molar volumes V-m(E) of (di-n-butyl ether (DBE) + a monofunctional organic compound) have been determined at T = 298.15 K over the whole composition range by means of a vibrating-tube densimeter. The V-m(E) values were either positive (propylamine, or butylamine, or acetone, or tetrahydrofuran + DBE) or negative (methanol, or butanol, or diethyl ether, or cyclopentanone, or acetonitrile + DBE). Markedly asymmetric V-m(E) curves were displayed by (DBE + methanol) and (DBE + acetonitrile). Partial molar volumes (V) over bar (0)(m) at infinite dilution in DBE, both from this work and the literature, were analysed in terms of an additivity scheme, and the group contributions thus obtained were discussed and compared with analogous results in water. DBE revealed a greater capability of distinguishing between polar and non-polar solutes, as well as in discriminating differently shaped molecules (unbranched, branched, cyclic). The limiting slopes of apparent excess molar volumes are evaluated and briefly discussed in terms of solute-solute and solute-solvent interactions. (C) 2001 Academic Press.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
