ENTHALPY OF INTERACTION OF TETRA-N-ALKYLAMMONIUM BROMIDES AND CSI WITH DIMETHYL-SULFOXIDE IN WATER AT 298.15-K

Excess enthalpies in water of dimethyl sulfoxide (DMSO) with various e lectrolytes (CsI, Me4NBr, Et4NBr, Pr4NBr, Bu4NBr and Pen(4)NBr) have b een determined by flow microcalorimetry at 298.15 K. Enthalpic pair in teraction coefficients, h(NE). Of the virial expansion of the mixing e nthalpy were calculated. The interaction of DMSO with CsI, Me4NBr, Et4 NBr gives negative and that with the remaining electrolytes gives posi tive coefficients. In the tetraalkylammonium series, h(NE) becomes inc reasingly positive when the number of carbon atoms in the hydrocarbon chain is increased. (C) 1997 Elsevier Science B.V.