Enthalpies of dilution and enthalpies of mixing of alpha-amino acids + pyridine and alpha-amino acids + methylpyridine in aqueous solutions at 298.15 K

摘要

The enthalpies of mixing of aqueous solutions have been determined for glycine and L-alanine with pyridine and methylpyridine by flow microcalorimetry at 298.15 K. In addition, the enthalpies of dilution at 298.15 K of aqueous solutions containing glycine, L-alanine, pyridine, and methylpyridine have been obtained, respectively. These data have been analyzed using the McMillan-Mayer theory, and heterotactic interaction coefficients are given for the interaction of glycine and L-alanine with pyridine and methylpyridine, among which the enthalpic pairwise interaction coefficients, h_(xy), are discussed in terms of solute-solute interaction and substituent effects.