Enthalpic interaction coefficients of glycine in aqueous sodium halide solutions at 298.15 K

The enthalpies of dilution have been measured for glycine in aqueous NaCl and NaBr solutions at 298.15 K using a flow microcalorimetry. The enthalpic interaction coefficients of glycine in the studied aqueous sodium halide solutions have been calculated according to the McMillanMayer model. Combining the previous studies for other sodium halides, the effect of the anions on enthalpic pairwise interaction coefficients between the glycine molecules has been rationalized in terms of the concepts of electrostatic interaction and structural interaction. The experimental data of the present work and those of the literature are combined, to put forward the general chemical principal, namely the more strongly solutes are solvated the less will be their tendency to interact with other solutes. (c) 2007 Elsevier B.V. All rights reserved.