Apparent Molar Volumes and Viscosities of Some α-Amino Acids in Aqueous Sodium Butyrate Solutions at 298.15 K

• Published in: Journal of chemical and engineering data Vol. 46; no. 2; pp. 217 - 222
• Main Authors: Yan, Zhenning, Wang, Jianji, Lu, Jinsuo
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 01.03.2001
• Subjects: Chemical thermodynamics; Chemistry; Exact sciences and technology; General and physical chemistry; Mixtures; Thermodynamic properties; Viscosity; α-Aminoacid; Electrolyte solution; Molar volume; Carboxylate; Apparent quantity; Aqueous solution; Experimental study; Thermodynamic properties; Density; Physical properties; Rheological properties
• ISSN: 0021-9568; 1520-5134
• DOI: 10.1021/je000211j

Densities and viscosities of aqueous solutions of α-amino acids (glycine, dl-alanine, dl-α-amino-n-butyric acid, dl-α-valine, and dl-α-leucine) + sodium butyrate have been measured as a function of concentrations of amino acid and electrolyte at 298.15 K. These data have been used to calculate apparent molar volumes and viscosity B-coefficients of the amino acids. The standard partial molar volumes, V°2, φ, standard volumes of transfer, Δt V°, and hydration numbers of the amino acids have been determined. It has been shown that V°2, φ, Δt V°, and the B-coefficient vary linearly with increasing number of carbon atoms in the alkyl chain of the amino acids, and they were split into contributions from the charged end group (NH3 +, COO-) and CH2 groups of the amino acids. From the volumetric data, we found that sodium butyrate interacts strongly with the charged center of the zwitterion of the amino acids and has a strong dehydration effect on the amino acids.