ABSTRACT

We have measured the densities at temperatures T = (278.15 to 368.15) K and heat capacities at T = (278.15 to 393.15) K of aqueous solutions of (18-crown-6 + NaCl) at molalities m = (0.02 to 0.30) mol kg-1 and at the pressure 0.35 MPa. We have also measured densities and heat capacities of mixtures containing excess 18-crown-6 and excess NaCl. We have applied Young's Rule and have accounted for chemical speciation and relaxation effects to resolve V and Cp, for (18-crown-6-Na+,Cl-)(aq) in the mixture. We have also calculated values of the change in volume rVm, the change in heat capacity rCp,m, the change in enthalpy rHm, and the equilibrium quotient log Q for formation of the aqueous (18-crown-6-Na+) complex at T = (278.15 to 393.15) K and m = (0 to 0.30) mol kg-1. These results are compared with those recently obtained for the complexes of 18-crown-6 with Ba2+ and K+.

Compounds

#	Formula	Name
1	C12H24O6	1,4,7,10,13,16-hexaoxacyclooctadecane
2	ClNa	sodium chloride
3	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	2 3 1	Apparent molar heat capacity, J/K/mol ; Liquid	Temperature, K; Liquid Molality, mol/kg - 1; Liquid Molality, mol/kg - 2; Liquid	Pressure, kPa; Liquid	Liquid	XDSC:UFactor:0.5	240
POMD	2 3 1	Apparent molar heat capacity, J/K/mol ; Liquid	Temperature, K; Liquid Molality, mol/kg - 1; Liquid Molality, mol/kg - 2; Liquid	Pressure, kPa; Liquid	Liquid	XDSC:UFactor:0.5	72
POMD	2 3 1	Apparent molar heat capacity, J/K/mol ; Liquid	Temperature, K; Liquid Molality, mol/kg - 1; Liquid Molality, mol/kg - 2; Liquid	Pressure, kPa; Liquid	Liquid	XDSC:UFactor:0.5	72
POMD	2 3 1	Apparent molar volume, m3/mol ; Liquid	Temperature, K; Liquid Molality, mol/kg - 1; Liquid Molality, mol/kg - 2; Liquid	Pressure, kPa; Liquid	Liquid	SAME:UFactor:0.5	110
POMD	2 3 1	Apparent molar volume, m3/mol ; Liquid	Temperature, K; Liquid Molality, mol/kg - 1; Liquid Molality, mol/kg - 2; Liquid	Pressure, kPa; Liquid	Liquid	SAME:UFactor:0.5	33
POMD	2 3 1	Apparent molar volume, m3/mol ; Liquid	Temperature, K; Liquid Molality, mol/kg - 1; Liquid Molality, mol/kg - 2; Liquid	Pressure, kPa; Liquid	Liquid	SAME:UFactor:0.5	22

Thermodynamics Research Center / ThermoML | Journal of Chemical Thermodynamics

Thermodynamics of complexation of aqueous 18-crown-6 with sodium ion: apparent molar volumes and apparent molar heat capacities of aqueous (18-crown-6 + sodium chloride) at temperatures (278.15 to 393.15) K, at molalities (0.02 to 0.30) mol*kg-1, and at the pressure 0.35 MPa.

Ziemer, S. P., Niederhauser, T. L., Woolley, E. M.[Earl M.]

ABSTRACT