ABSTRACT

The enthalpies of solution of ordinary (H2O) and heavy (D2O) water in dimethylsulphoxide (DMSO), N,N-dimethylformamide (DMF) and N,N-dimethylacetamide (DMA) have been measured using an isoperibol sealed calorimeter at 298.15 K. Standard (at infinite dilution) enthalpies of solution and solvation, together with D2O-H2O solute isotope effects on the quantities in question, were calculated. The enthalpies of solution of water H/D isotopologues have been found to be negative by sign and increasing in magnitude on going from DMF to DMSO and DMA. The corresponding positive solute isotope effects are very insignificant and slightly increases in a consequence: DMF less than DMSO . DMA. It has been concluded that the enthalpy-isotopic effects of water solvation are qualitatively connected with the donor-accepting and structure-packing properties of the aprotic dipolar solvents compared.

Compounds

#	Formula	Name
1	C2H6OS	dimethyl sulfoxide
2	H2O	water
3	C3H7NO	dimethylformamide
4	C4H9NO	N,N-dimethylethanamide
5	D2O	water-d2

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	Phase	Method	#Points
POMD	1 2	Molar enthalpy of solution, kJ/mol ; Liquid	Molality, mol/kg - 2; Liquid Pressure, kPa; Liquid Temperature, K; Liquid	Liquid	ISOPERIBOL	1
POMD	3 2	Molar enthalpy of solution, kJ/mol ; Liquid	Molality, mol/kg - 2; Liquid Pressure, kPa; Liquid Temperature, K; Liquid	Liquid	ISOPERIBOL	1
POMD	4 2	Molar enthalpy of solution, kJ/mol ; Liquid	Molality, mol/kg - 2; Liquid Pressure, kPa; Liquid Temperature, K; Liquid	Liquid	ISOPERIBOL	1
POMD	1 5	Molar enthalpy of solution, kJ/mol ; Liquid	Molality, mol/kg - 5; Liquid Pressure, kPa; Liquid Temperature, K; Liquid	Liquid	ISOPERIBOL	1
POMD	3 5	Molar enthalpy of solution, kJ/mol ; Liquid	Molality, mol/kg - 5; Liquid Pressure, kPa; Liquid Temperature, K; Liquid	Liquid	ISOPERIBOL	1
POMD	4 5	Molar enthalpy of solution, kJ/mol ; Liquid	Molality, mol/kg - 5; Liquid Pressure, kPa; Liquid Temperature, K; Liquid	Liquid	ISOPERIBOL	1

Thermodynamics Research Center / ThermoML | Thermochimica Acta

Water as a solute in aprotic dipolar solvents. 3. D2O-H2O solute isotope effects on the enthalpy of water dissolution in dimethylsulphoxide, N,N-dimethylformamide and N,N-dimethylacetamide at 298.15 K

Ivanov, E. V.[Evgeniy V.], Smirnov, V. I.[Valeriy I.]

ABSTRACT