Viscosity B-coefficients between 5° and 20° for glycolamide, glycine, and N-methylated glycines in aqueous solution

Abstract

The significance of viscosity B-coefficients for solutions of dipolar ions and non-electrolytes in water is discussed in the light of hydrodynamic theories of viscosity and the usefulness of the ratio B / W , ((Do2 is the limiting apparent molar volume of the solute) is stressed. Viscosity and density measurements have been made at 5", 1 O", 1 5". and 20" on aqueous solutions of glycolamide, glycine, sarcosine, dimethyglycine, and betaine. Apparent molal volumes and viscosity B-coefficients have been calculated from these data. The results suggest that a charged nitrogen atom bearing 3 or 2 hydrogen atoms interacts strongly with the solvent water to form a primary solvation sheath.Substitution of two of the three hydrogen atoms. as in dimethylglycine, leads to a considerable reduction in solvation, and complete substitution, as in betaine, seems to prevent it entirely.

Rheological behaviour of some saccharides in aqueous potassium chloride solutions over temperature range (288.15 to 318.15)K

“…Further B-coefficients of studied saccharides and methylglycosides in water and aqueous solutions of KCl decrease with temperature. The negative dB/dT values (table 2) are indicative of the structure-making propensity as suggested by Tyrrell and Kennerley [27]. The negative magnitude is found to increase from mono-, to di-, to tri-saccharides.…”

Effect of sodium acetate on the rheological behaviour of some mono-, di-, and tri-saccharides in aqueous solutions over the temperature range (288.15 to 318.15)K

“…The temperature dependence of viscosity B-coefficients provides information regarding the structure-making and -breaking effect of the electrolytes [20]. The dB/dT values for sodium acetate are: À0.00111 m 3 Á mol À1 Á K À1 , thereby showing that sodium acetate acts as a structure maker.…”

Effect of Temperature and Concentration on the Viscosity of Perchloric Acid

“…The viscosity B-coefficient follows the order: 1.0 to 4.0 mol dm -3 < 4.0 to 6.0 mol dm -3 < 6.0 to 9.0 mol dm -3 . The positive value of viscosity B-coefficient shows that perchloric acid in aqueous solution acts as structure maker [28,29].…”

“…1: where η/ηo is relative viscosity, η is viscosity of solution, ηo is viscosity of solvent, A is a constant (A-coefficient) which is the measure of solute-solute interaction; B is a constant (Bcoefficient) which is the measure of solute-solvent interaction [29,30] and c is the concentration of HClO4 (Table-1). JonesDole plot for aqueous perchloric acid at 283.65 K is given in Fig.…”