Solubility of ΓƒΖ’Γ‚Ζ’Γƒβ€šΓ‚Ζ’ΓƒΖ’Γ‚β€šΓƒβ€šΓ‚Β‘-amino butyric acid in water-NaNO3 mixture and analysis of related thermodynamic parameters

S.Roy, K.Mahali, S.Pal, S.Mond

Abstract

Solubility data of DL-á-amino butyric acid are obtained, using the ÂΓƒβ€šΓ‚β€˜formal titrimetryÂΓƒβ€šΓ‚β€™ method in water and aqueous solution with various sodium nitrate (NaNO3) concentrations in the temperatures 288.15, 293.15, 298.15, 303.15 and 308.15 K. The standard transfers Gibbs energies and entropies have been evaluated for this amino acid from water to aqueous mixture of sodium nitrate solution at 298.15 K. The chemical effects of the transfer Gibbs energies ( 0 ( ) , G i t ch ïΓƒβ€šΓ‚ΒΓƒβ€šΓ‚β€ž ), obtained by subtracting theoretically computed G0 (i) t ïΓƒβ€šΓ‚ΒΓƒβ€šΓ‚β€ž due to cavity and dipole-dipole interactions effects from the total transfer free energies, G (i) 0 t ïΓƒβ€šΓ‚ΒΓƒβ€šΓ‚β€ž .Again S (i) 0 t ,ch ïΓƒβ€šΓ‚ΒΓƒβ€šΓ‚β€ïΓƒβ€šΓ‚ΒΓƒβ€šΓ‚β€ž have been evaluated after elimination of cavity effect and dipole-dipole interaction effects from total transfer ( T S (i) 0 t ïΓƒβ€šΓ‚ΒΓƒβ€šΓ‚β€ž ) entropies. The various solvent parameters as well as thermodynamic parameters likemolar volume, densities, dipole moment and solvent diameter of aqueous solution of sodium nitrate (NaNO3) have also been reported in this manuscript. The results show that the solubility is affected by the electrolyte (NaNO3) and the stability of the amino acid is affected by the electrolyte which is discussed in terms of various types of thermodynamic interactions.

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