ABSTRACT

The enthalpies of transfer of formamide (Form)N-methylformamide (NMF) andN,N-dimethylformamide (DMF) fromwater to aqueous methanol mixtures are reported and analysed in terms of the new solvation theory. It was found that a previous equation could not reproduce these data over the whole range of solvent compositions. Using the new solvation theory to reproduce the enthalpies of transfer shows excellent agreement between the experimental and calculated data over the entire range of solvent compositions. The analyses show that the solvation of DMF is random in the aqueous methanol mixtures while Form and NMF are preferentially solvated by methanol. It is also found that the interaction of the solutes is stronger with methanol than with water.

Compounds

#	Formula	Name
1	CH4O	methanol
2	H2O	water
3	CH3NO	formamide
4	C2H5NO	N-methylformamide
5	C3H7NO	dimethylformamide

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 2	Excess molar enthalpy (molar enthalpy of mixing), kJ/mol ; Liquid	Mole fraction - 1; Liquid	Temperature, K; Liquid Pressure, kPa; Liquid	Liquid	Titration calorimetry	13
POMD	1 3 2	Molar enthalpy of solution, kJ/mol ; Liquid	Solvent: Mole fraction - 1; Liquid	Temperature, K; Liquid Pressure, kPa; Liquid Mole fraction - 3; Liquid	Liquid	Titration calorimetry	13
POMD	1 4 2	Molar enthalpy of solution, kJ/mol ; Liquid	Solvent: Mole fraction - 1; Liquid	Temperature, K; Liquid Pressure, kPa; Liquid Mole fraction - 4; Liquid	Liquid	Titration calorimetry	13
POMD	1 5 2	Molar enthalpy of solution, kJ/mol ; Liquid	Solvent: Mole fraction - 1; Liquid	Temperature, K; Liquid Pressure, kPa; Liquid Mole fraction - 5; Liquid	Liquid	Titration calorimetry	13
POMD	3 2	Molar enthalpy of solution, kJ/mol ; Liquid	Temperature, K; Liquid Pressure, kPa; Liquid Mole fraction - 3; Liquid		Liquid	Titration calorimetry	1
POMD	1 3	Molar enthalpy of solution, kJ/mol ; Liquid	Temperature, K; Liquid Pressure, kPa; Liquid Mole fraction - 3; Liquid		Liquid	Titration calorimetry	1
POMD	4 2	Molar enthalpy of solution, kJ/mol ; Liquid	Temperature, K; Liquid Pressure, kPa; Liquid Mole fraction - 4; Liquid		Liquid	Titration calorimetry	1
POMD	1 4	Molar enthalpy of solution, kJ/mol ; Liquid	Temperature, K; Liquid Pressure, kPa; Liquid Mole fraction - 4; Liquid		Liquid	Titration calorimetry	1
POMD	5 2	Molar enthalpy of solution, kJ/mol ; Liquid	Temperature, K; Liquid Pressure, kPa; Liquid Mole fraction - 5; Liquid		Liquid	Titration calorimetry	1
POMD	1 5	Molar enthalpy of solution, kJ/mol ; Liquid	Temperature, K; Liquid Pressure, kPa; Liquid Mole fraction - 5; Liquid		Liquid	Titration calorimetry	1

Thermodynamics Research Center / ThermoML | Thermochimica Acta

A new equation to reproduce the enthalpies of transfer of formamide, N-methylformamide and N,N-dimethylformamide from water to aqueous methanol mixtures at 298K

Behbehani, G. R., Ghamamy, S.

ABSTRACT