scholarly journals Solution thermodynamics of sodium pyruvate in aqueous glycine solutions at T 298.15-313.15 K

2016 ◽  
Vol 81 (11) ◽  
pp. 1283-1294 ◽  
Author(s):  
Bijan Pandit ◽  
Abhijit Sarkar ◽  
Biswajit Sinha

In this study we investigated the effects of sodium pyruvate on the solution thermodynamics of glycine in terms of the solute-solute and solute-solvent interactions in aqueous solutions. Measured density and viscosity were used to derive apparent molar volumes (?V), standard partial molar volumes (?V0) and viscosity B-coefficients at 298.15, 303.15 K, 308.15, and 318.15 K under ambient pressure. The interactions are further discussed in terms of ion-dipolar, hydrophobic- hydrophobic, hydrophilic-hydrophobic group interactions. The activation parameters of viscous flow were also discussed in terms of transition state theory. The overall results indicated that ion-hydrophilic and hydrophilic-hydrophilic group interactions are predominant in the ternary solutions.

2013 ◽  
Vol 78 (8) ◽  
pp. 1225-1240 ◽  
Author(s):  
Abhijit Sarkar ◽  
Biswajit Sinha

In this study we investigated the effects of tetrabutylammonium hydrogen sulphate (Bu4NHSO4) on the solute-solute and solute-solvent interactions in the aqueous solutions of nicotinic acid in terms of apparent molar volumes (?V), standard partial molar volumes (?V0) and viscosity B-coefficients at 298.15, 308.15, and 318.15 K under ambient pressure. These interactions are further discussed in terms of ion-dipolar, hydrophobic- hydrophobic, hydrophilic-hydrophobic group interactions. The activation parameters of viscous flow for Bu4NHSO4 in the aqueous solutions of nicotinic acid were discussed in terms of transition state theory. The overall results indicated that ion-hydrophilic and hydrophilic-hydrophilic group interactions are predominant in the aqueous solutions of nicotinic acid and Bu4NHSO4 has a dehydration effect on the hydrated nicotinic acid.


2014 ◽  
Vol 79 (2) ◽  
pp. 225-239 ◽  
Author(s):  
Dhiraj Brahman ◽  
Biswajit Sinha

In this study partial molar volumes (?V0) and viscosity B-coefficients of iron(III)-N, N'-ethylene-bis(salicylideneiminato)-chloride, abbreviated as FeIII(salen)Cl, in different aqueous methanol solutions were determined from solution density and viscosity measurements at temperatures 298.15, 303.15, and 313.15 K under ambient pressure. Apparent molar volumes (?V) and densities (?) were used to calculate the apparent molar expansibilities (?E), the partial molar expansibilities (?E0) and the temperature dependence of the partial molar expansibilities (?E0) at constant pressure, (??E0/?T)P of FeIII(salen)Cl solutions to reveal the nature of different interactions in the ternary solutions. The transition state theory was applied to analyze the viscosity B-coefficients on the basis of the activation parameters of viscous flow. The overall results indicated strong solute-solvent interactions between FeIII(salen)Cl and the solvent molecules, preferentially with water molecules and that FeIII(salen)Cl acts as a net structure promoter in the ternary solutions. UV-VIS absorption spectra of the ternary solutions also stand in support of the results obtained.


2007 ◽  
Vol 72 (5) ◽  
pp. 495-512 ◽  
Author(s):  
A. Ali ◽  
S. Khan ◽  
F. Nabi

Densities, ?, viscosities, ? and refractive indices, n D, of solutions of some amino acids (glycine, DL-alanine, DL-? -amino- n-butyric acid, L-valine and L-leucine) in the concentration range 0.02 to 0.10 m in 5 % (v/v) aqueous glycerol were determined at 298.15, 303.15, 308.15 and 313.15 K. These experimental data were used to calculate the apparent molar volumes, ? v, the infinite dilution apparent molar volumes, ? v 0, the partial molar volumes of transfer, ? v 0 (tr), of the amino acids from aqueous to aqueous glycerol solution, as well as the viscosity A and B coefficients of the Jones-Dole equation of the amino acids. The free energies of activation of viscous flow, ??1 0# and ?? 2 0# per mole of solvent and solute, respectively, were obtained by application of the transition-state theory to the B coefficient data and the corresponding activation enthalpy, ?H*, and entropy, ?S*, were also determined. The ? v 0, B coefficients and ?? 2 0# were found to vary linearly with increasing number of carbon atoms in the alkyl chain of the amino acids, and they were split into contributions from the zwitterionic end groups (NH3 +, COO-) and methylene (CH2) groups of the amino acids. The experimental values of the refractive indices, n D, were used to calculate the molar refractive indices, R D, of the amino acids + aqueous glycerol ternary mixtures. The results were interpreted in the light of the solute-solvent and solute-solute interactions in the mixed solvents.


Author(s):  
Sanjeevan J. Kharat ◽  
Sachin M. Munde

Densities of sodium cyclamate (Na-cycl) in water and (0.1, 0.3, and 0.5)m(glucose/sucrose) have been measured at (298.15, 303.15, 308.15, and 313.15) K. From density values, partial molar volumes (V0Φ), expansion coefficient (E∞), Hepler’s constant (δ2V0Φ/δT2)p, apparent specific volumes (ASV), partial molar volumes of transfer (∆trsV0Φ), doublet (VAB) and triplet (VABB) interaction coefficients have been calculated. An increase in the values ofV0Φand ∆trsV0Φwas observed with increase in the concentration of glucose/sucrose. The positive values ofE∞ andV0Φare due to the strong solute-solvent interactions. The positive values of (δ2V0Φ/δT2)psuggest structure making behaviour of sodium cyclamate in water and in presence of glucose and sucrose. The positive values of (∆trsV0Φ) andVABmay be due to the interactions between hydrophilic group (–OH, C=O, and –O–) of glucose/sucrose and sodium ion of sodium cyclamate. All solutions studied exhibit sweet taste because ASV of all solutions ranges from (0.569 × 10-6) m3×kg-1to (0.626 × 10-6) m3×kg-1.


2009 ◽  
Vol 64 (11) ◽  
pp. 758-764 ◽  
Author(s):  
Anwar Ali ◽  
Rajan Patel ◽  
Shahjahan Khan ◽  
Vidiksha Bhushan

The densities (ρ), viscosities (η), and refractive indices (nD) of (0.01, 0.05, 0.10, 0.15, and 0.20 m) amino acid, glycine, and peptides, diglycine and triglycine in 0.01 m aqueous tartrazine solution were determined at 288.15, 293.15, 298.15, 303.15, 308.15, and 313.15 K. The density data were utilized to evaluate apparent molar volumes (φv) which, in turn, were used to determine partial molar volumes (φv ◦) using Masson’s equation. The transfer volumes were also calculated. The viscosity data were analyzed using the Jones-Dole equation to determine the viscosity coefficients and the activation parameters. The activation parameters of viscous flow were obtained to throw light on the mechanism of viscous flow. The molar refraction was calculated using the refractive index data. The results were interpreted in the light of ion-ion, ion-nonpolar, and nonpolar-nonpolar interactions and the effect of increasing hydrophobicity as we move from glycine to triglycine on these interactions in presence of the dye tartrazine was also investigated.


2008 ◽  
Vol 73 (12) ◽  
pp. 1235-1246 ◽  
Author(s):  
Nath Roy ◽  
Lovely Sarkar ◽  
Kumar Sarkar

The apparent molar volumes, ?V, and viscosity B-coefficients, B, for nicotinic acid (NA) and benzoic acid (BA) in mixed solvents containing 10, 20, 30 mass % of n-amyl alcohol (n-AmOH) or isoamyl alcohol (i-AmOH) in methanol and in pure methanol (MeOH) were determined from the solution density and viscosity measurements at 298.15 K as function of concentrations of NA and BA. These results were, in conjunction with the results obtained in pure methanol, used to deduce the partial molar volumes of transfer, 0 ??V , and viscosity B-coefficients of transfer, ?B, for NA and BA from methanol to different mixed methanol solvents, in order to rationalize various interactions in the ternary solutions. An increase in the transfer properties of NA and BA with increasing mass % of n-AmOH and i-AmOH in methanol was observed and explained by the effect of structural changes and preferential solvation. Also, the free energies of viscous flow, ? 0? 1 ? and ? 0? ?2 , per mole of solvent and solute, respectively, were calculated and analyzed on the basis of the transition state theory of relative viscosity.


Sign in / Sign up

Export Citation Format

Share Document