ABSTRACT

The dissolution enthalpy of 1,4,7,10,13-pentaoxacyclopentadecane (15-crown-5) and 1,4,7,10,13,16- hexaoxacyclooctadecane (18-crown-6) ethers in the mixture of water and N,N-dimethylformamide (DMF) was measured within the range from (293.15 to 308.15) K. The values of standard molar enthalpies of solution, AsolHm o , of crown ethers: 15-crown-5 and 18-crown-6 in the mixture of water and N,Ndimethylformamide within the range of the mixture composition under investigation, increase linearly with increasing temperature. The values of partial molar heat capacity, Cp,2 o , and hydrophobic hydration effect, Hb(H2O), were determined. The effect of temperature on the process of hydrophobic hydration of crown ethers has been interpreted. The values of the enthalpic effect of hydrophobic hydration are more negative for 18-crown-6 than those for 15-crown-5. The exothermic enthalpic effect of hydrophobic hydration, Hb(H2O), of the crown ethers under investigation decreases linearly with increasing temperature.

Compounds

#	Formula	Name
1	C10H20O5	1,4,7,10,13-pentaoxacyclopentadecane
2	C12H24O6	1,4,7,10,13,16-hexaoxacyclooctadecane
3	H2O	water
4	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	4 3 1	Molar enthalpy of solution, kJ/mol ; Liquid	Temperature, K; Liquid Solvent: Mole fraction - 3; Liquid	Pressure, kPa; Liquid Mole fraction - 1; Liquid	Liquid	ISOPERIBOL	60
POMD	4 3 2	Molar enthalpy of solution, kJ/mol ; Liquid	Temperature, K; Liquid Solvent: Mole fraction - 3; Liquid	Pressure, kPa; Liquid Mole fraction - 2; Liquid	Liquid	ISOPERIBOL	60
POMD	4 1	Molar enthalpy of solution, kJ/mol ; Liquid	Temperature, K; Liquid	Pressure, kPa; Liquid Mole fraction - 1; Liquid	Liquid	ISOPERIBOL	4
POMD	3 1	Molar enthalpy of solution, kJ/mol ; Liquid	Temperature, K; Liquid	Pressure, kPa; Liquid Mole fraction - 1; Liquid	Liquid	ISOPERIBOL	4
POMD	4 2	Molar enthalpy of solution, kJ/mol ; Liquid	Temperature, K; Liquid	Pressure, kPa; Liquid Mole fraction - 2; Liquid	Liquid	ISOPERIBOL	4
POMD	3 2	Molar enthalpy of solution, kJ/mol ; Liquid	Temperature, K; Liquid	Pressure, kPa; Liquid Mole fraction - 2; Liquid	Liquid	ISOPERIBOL	4

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

Effect of Temperature on the Process of Hydrophobic Hydration. Part II. Hydrophobic Hydration of 15-Crown-5 and 18-Crown-6 Ethers

Jozwiak, M.[Malgorzata], Kosiorowska, M. A.[Monika A.], Wasiak, M.[Michal]

ABSTRACT