ABSTRACT

The dilution enthalpies of l-alanine in dimethylsulfoxide (DMSO) + water and dimethylformamide (DMF) + water mixtures at 298.15 K have been determined, respectively, using an isothermal titration calorimeter. On the basis of the McMillan-Mayer theory, the homochiral enthalpic interaction coefficients hXX of l-alanine in both of the mixtures of various mass fractions (w2 = 0 to 0.3) have been calculated. It was found that hXX is positive at lower DMSO or DMF concentrations, but it becomes less positive and even negative with the increasing concentration of DMSO or DMF. The results were interpreted from the point of view of solute-solute interactions mediated by these two aprotic cosolvents.

Compounds

#	Formula	Name
1	C2H5NO2	2-aminoacetic acid
2	C3H7NO2	(S)-2-aminopropanoic acid
3	C3H7NO3	L-serine
4	C2H6OS	dimethyl sulfoxide
5	C3H7NO	dimethylformamide
6	H2O	water

Datasets

The table above is generated from the ThermoML associated json file (link above). POMD and RXND refer to PureOrMixture and Reaction Datasets. The compound numbers are included in properties, variables, and phases, if specificied; the numbers refer to the table of compounds on the left.
Type	Compound-#	Property	Variable	Constraint	Phase	Method	#Points
POMD	1 6	Molar enthalpy of dilution, kJ/mol ; Liquid	Initial molality of solute, mol/kg; Liquid Final molality of solute, mol/kg; Liquid	Temperature, K; Liquid Pressure, kPa; Liquid	Liquid	isothermal titration calorimetry	14
POMD	3 6	Molar enthalpy of dilution, kJ/mol ; Liquid	Initial molality of solute, mol/kg; Liquid Final molality of solute, mol/kg; Liquid	Temperature, K; Liquid Pressure, kPa; Liquid	Liquid	isothermal titration calorimetry	15
POMD	2 6	Molar enthalpy of dilution, kJ/mol ; Liquid	Initial molality of solute, mol/kg; Liquid Final molality of solute, mol/kg; Liquid	Temperature, K; Liquid Pressure, kPa; Liquid	Liquid	Isothermal titration calorimeter	15
POMD	2 4 6	Molar enthalpy of dilution, kJ/mol ; Liquid	Solvent: Volume fraction - 4; Liquid Initial molality of solute, mol/kg; Liquid Final molality of solute, mol/kg; Liquid	Temperature, K; Liquid Pressure, kPa; Liquid	Liquid	isothermal titration calorimeter	115
POMD	2 5 6	Molar enthalpy of dilution, kJ/mol ; Liquid	Solvent: Volume fraction - 5; Liquid Initial molality of solute, mol/kg; Liquid Final molality of solute, mol/kg; Liquid	Temperature, K; Liquid Pressure, kPa; Liquid	Liquid	isothermal titration calorimeter	84

Thermodynamics Research Center / ThermoML | Journal of Chemical and Engineering Data

Enthalpies of Dilution of l-Alanine in Dimethylsulfoxide + Water and Dimethylformamide + Water Mixtures at 298.15 K

Zhang, H.[Hejuan], Hu, X.[Xingen], Shao, S.[Shuang]

ABSTRACT