Abstract
The densities (rho), viscosities (eta), and refractive indices (n(D)) of (0.10, 0.15, 0.20, 0.25, and 0.30) m glycine, L-alanine, and L-valine were measured in 0.01 m aqueous tartrazine at 288.15, 293.15, 298.15, 303.15, 308.15, and 313.15 K. The measured data were utilized to evaluate various useful parameters, viz., apparent molar volume, (phi(v)), partial molar volume, (phi(0)(v)), partial molar isobaric expansibility, (phi(0)(E)), transfer volume (phi(0)(v)((tr))), A and B-coefficients of viscosity, free energy of activation of viscous flow per mole of solvent (Delta mu(1)*) and solute (Delta mu(2)*) and molar refractivity (R-D). The linear variation of phi(0)(v) with the number of carbon atoms (n(C)) present in the alkyl chain of amino acids was also considered for the evaluation of the contribution of zwitterionic end groups (NH3+, COO-) and methylene groups to phi(0)(v). The results were used to discuss ion-ion, ion-nonpolar and nonpolar-nonpolar interactions and the presence of structural hydration in the present systems.