Application of the New Solvation Theory to Reproduce the Enthalpies of Transfer of LiBr, Tetrabutylammonium Bromide and Tetrapentylamonium Bromide from Water to Aqueous Acetonitrile at 298 KG.

Rezaei Behbehani
Department of Chemistry, Imam Khomeini International University Qazvin Iran, E-mail:

The enthalpies of transfer, DHqt, of LiBr, tetrabutylammonium bromide, n-Bu4NBr, and tetrapentylamonium bromide, n-Pen4NBr, from water to aqueous acetonitrile solvent system are reported and analyzed in terms of the new developed solvation theory. The solvation parameters obtained from the analyses indicate that the net effect of tetraalkylammonium bromides on solvent structure is a breaking of solvent-solvent bonds and thus tetraalkylammonium bromides is preferentially solvated by acetonitrile. Preferential solvation of tetraalkylammonium bromides by acetonitrile is consistent with hydrophobisity of these compounds. LiBr is preferentially solvated by water.  

Key words: preferential solvation, variable (an + bN), solvent-solvent bonds