Solubility and transfer Gibbs free energetics of glycine, DL-alanine, DL-nor-valine and DL-serine in aqueous sodium fluoride and potassium fluoride solutions at 298.15 K

The experimental saturated solubilities of glycine, DL-alanine, DL-nor-valine and DL-serine in aqueous mixtures of NaF and KF solutions at 298.15 K are measured by using an analytical ‘formol titrimetry’ method. Subsequently, the standard transfer Gibbs free energy, enthalpy for cavity formation, Gibbs free energy for cavity formation and Gibbs free energy for dipole-dipole interaction have been computed. The chemical contribution for the standard transfer Gibbs free energies for the experimental amino acids have been obtained by subtracting the cavity effects and dipole-dipole interaction effects from the total standard transfer Gibbs free energy (∆ (i)). The stability of the studied amino acids in aqueous NaF and KF in terms of thermodynamic parameters are discussed and compared

Solubility and transfer Gibbs free energetics of glycine, DL-alanine, DL-nor-valine and DL-serine in aqueous sodium fluoride and potassium fluoride solutions at 298.15 K

399-406The experimental saturated solubilities of glycine, DL-alanine, DL-nor-valine and DL-serine in aqueous mixtures of NaF and KF solutions at 298.15 K are measured by using an analytical ‘formol titrimetry’ method. Subsequently, the standard transfer Gibbs free energy, enthalpy for cavity formation, Gibbs free energy for cavity formation and Gibbs free energy for dipole-dipole interaction have been computed. The chemical contribution for the standard transfer Gibbs free energies for the experimental amino acids have been obtained by subtracting the cavity effects and dipole-dipole interaction effects from the total standard transfer Gibbs free energy (∆ (i)). The stability of the studied amino acids in aqueous NaF and KF in terms of thermodynamic parameters are discussed and compared

Solubility and Thermodynamics of Solute–Solvent Interactions of Some Amino Acids in Aqueous Sodium Bromide and Potassium Bromide Solutions

The study presents the saturated solubilities of four amino acids such as glycine, dl-alanine, dl-valine, and dl-serine in water media containing sodium bromide and potassium bromide electrolytes at standard temperature (298.15 K) which were evaluated by applying the “gravimetric method”. Various physicochemical and thermodynamical parameters such as enthalpy of solvation, free energy change, density, molar volume, solvent diameter, cosolvent diameter, apparent dipole moment of aqueous electrolyte systems, mole fraction of salt and solvent, mean molecular weight of electrolyte solvent and isothermal expansibility constant of aqueous electrolytes were estimated at standard temperature (298.15 K). The characteristics and degree of solubilities of the experimental molecules in water media in the presence of NaBr and KBr were examined by means of the salting-in effect which was further justified by relative solubility and salting-in constants. Various reasonings influencing the solubility were introduced and interrelated with appropriate thermodynamical issues. Ultimately the chemical transfer Gibbs free energies were measured and used to justify the stability of the experimental molecules in water media in the presence of electrolytes