Apparent molal volumes, apparent molal compressibilities, and their isotope effects : in aqueous and non-aqueous carbohydrate solutions

Apparent molal volumes and compressibilities of aqueous and non-aqueous solutions including their isotope effects were investigated. The apparent molal volumes were derived from densities measured with a vibrating tube densitometer. Aqueous solution limiting apparent molal volumes and expansibilities are reported for glucose, sucrose, fructose, and myo-inositol at various temperatures. The concentration dependence of the molar volume isotope effect and the temperature dependence of the limiting values are given for glucose, sucrose, and myo-inositol. Non-aqueous limiting apparent molal volumes are reported for glucose in DMSO, DMSO-d₆, DMF, and ethylene glycol, galactose in DMSO, sucrose in DMSO and DMF, a-methyl glucoside in DMSO, DMF, and methanol, and α-methyl glucoside in DMSO. The apparent molal adiabatic compressibility were obtained from sound speeds mea-sured with two "sing-around" ultrasonic velocimeters. Aqueous limiting apparent molal adiabatic compressibilities are presented for glucose, sucrose, fructose, and myo-inositol at 15 and 25°C. Iso-thermal values at 25° are also reported. Non-aqueous limiting apparent molal adiabatic compressibilities are given for glucose, sucrose, α- and β-methyl glucosides in DMSO, and glucose in DMF.

A correlation between the isothermal compressibility of the solvent and the limiting apparent molal volume is examined. The results are rationalized and, when possible, compared with literature data.