Apparent Molar Volumes of L-Serine and L-Threonine in Methanol-Water Mixtures

Department of Chemistry, Punjabi University, Patiala-147 002 Manuscript received 30 December 1985, accepted 12 August 1986 Apparent molar volumes (\(\phi\)v) of L-serine in water, 10, 20 and 30% (w/w) methanol—water mixtures, and of L-threonine in water, 10, 15 and 20% methanol –water mixtures have been obtained from measurements of density at 25, 35 and 45', respectively. The limiting values \(\phi_v^o\) have been calculated by a linear extrapolation using the least-squares method. These data have been used to derive the solvation number (\(n\)s) of L-serine and L-threonine. The \(n\)s values obtained increase with the addition of methanol for both the amino acids and at all temperatures