Volumetric properties of d-galactose in aqueous HCl solution at 278.15 to 318.15 K

Abstract

Densities have been measured for d-galactose + HCl + water at 10° intervals from 278.15 to 318.15 K. The apparent molar volumes ( V Φ,Gal) and standard apparent molar volumes ( V 0 Φ,Gal) for d-galactose in aqueous solutions of 0.2 ~ 2.1 mol kg − 1 HCl have been calculated. Volumetric interaction parameters of galactose with HCl in water have also been obtained from transfer volumes. Results show that V Φ,Gal and V 0 Φ,Gal for galactose in aqueous HCl solutions increase with increasing molality of HCl. At a given temperature, the standard transfer apparent molar volumes (Δ t V 0 Φ,Gal) for galactose from water to aqueous HCl solutions are positive and increase with increasing molality of HCl. In the investigated temperature range, the relation: V 0 Φ,Gal = b 0 + b 1( T − 273.15 K) 0.77 can be used to describe the temperature dependence of the standard apparent molar volumes. Values of standard partial molar isobaric expansion coefficient ( ∂V 0 Φ,Gal/ ∂T) p are positive and decrease with increasing temperature and molalities of HCl.