Volumetric Properties of Dilute Solutions of Water in Acetone between 288.15 and 318.15 K

Water as a solute in nitromethane: Effect of H2O–D2O isotope substitution on the solution volumetric properties between 278.15K and 318.15K

“…The normalizing factor 55.50843 (numerically equal to the number of H 2 O moles in 1 kg of water) is introduced in order for c sm and molality m in aqueous (H 2 O) solutions to coincide numerically. As shown previously [18,41,44], the use of c sm scale reduces an error in the definition of the apparent molar volumes, V /,2 , of the solute at high dilutions. The final concentration of NM was no more than c sm $ 1.66 units (or x 2 $ 0.029).…”

“…The b i coefficients of equation (3) as well as the V 1 values from equation (4) are given in table 4. For calculating the limiting quantities V 1 /;2 V 1 2 (also see table 4), the smoothed density values and a rational procedure [41,59] showing a good performance [11][12][13][14]18,44,60] were employed. This procedure is distinguished by an improved stability of the V /,2 values to the effects of uncertainties in solution densities and compositions in the highly dilute region.…”

D2O–H2O solvent isotope effects on the volumetric properties of aqueous 1,3-dimethyl-2-imidazolidinone between (278.15 and 318.15)K

“…The values of V u,2 and V 1 /;2 ð V 1 2 Þ were computed by applying a rational procedure [13,32,34]. This procedure is distinguished by an improved stability of the experimental V u,2 (n 2 ) values to the effects of uncertainties in solution densities and compositions in the highly dilute region.…”

“…Solutions were prepared gravimetrically (with using an analytical VLR-200 balance) by diluting the degassed '' mother" solvent with the accuracy to 5Á10 À5 units of c sm , where c sm is the solvomolality being a dimensionless rational parameter of the solution composition and, unlike aquamolality [9,31], expressing the solute concentration not only in aqueous but also in non-aqueous media [13,[32][33][34]. Namely, c sm = 55.50843n 2 /n 1 = 55.50843x 2 /x 1 , where n 1 (x 1 ) and n 2 (x 2 ) are the number of moles (mole-fractions) of the solvent and solute, respectively.…”

“…The normalizing factor 55.50843 (numerically equal to the number of H 2 O moles in 1 kg of water) is introduced in order for c sm and molality m in aqueous (H 2 O) solutions to coincide numerically. The use of this concentration scale is of crucial importance for interpretation of the thermodynamic functions of transfer (including D 2 O-H 2 O isotope effects), because the ratio of the number of the solvent particles to the number of the solute particles remains constant on going from one solvent (H 2 O) to another (D 2 O) [13,34]. Moreover, as shown below, the use of c sm scale reduces an error in the definition of the apparent molar volumes of the solute, V u,2 , at high dilutions.…”