Effect of Hydroxylamine Sulfate on Volumetric Behavior of Glycine,L-Alanine, andL-Arginine in Aqueous Solution

The apparent molar volumes of glycine,L-alanine, andL-arginine in aqueous hydroxylamine sulfate solutions have been determined atT=298.15 K and atmospheric pressure. The standard partial molar volumes,V20, corresponding partial molar volumes of transfer,ΔtrV20, and hydration numbers,NH, have been calculated for theseα-amino acids from the experimental data. TheΔtrV20values are positive for glycine,L-alanine, andL-arginine and are all increased with the increase in the concentration of hydroxylamine ions. These parameters obtained from the volumetric data are interpreted in terms of various mixing effects between amino acids and hydroxylamine sulfate in aqueous solutions.