ABSTRACT

The enthalpies of dilution of protocatechualdehyde and p-hydroxybenzaldehyde in the aqueous sodium chloride solutions were measured by using a mixing-flow microcalorimeter at 298.15 K. Densities of the ternary homogeneous systems at different temperatures (293.15, 298.15, 303.15, 308.15, and 313.15 K) were also measured with a quartz vibrating-tube densimeter. The homogeneous enthalpic interaction coefficients (h2, h3, and h4) were calculated according to the excess enthalpy concept based on the calorimetric data. The apparent molar volumes (V) and standard partial molar volumes (V0) of the investigated system were computed from their density data. The variation trends in h2 and V0 with increasing salt molality were obtained and discussed in terms of the (solute + solute) and (solute + solvent) interactions. The experimental results showed that the molecular structures of protocatechualdehyde and p-hydroxybenzaldehyde, especially the number of hydroxyl groups, have evident influence on their thermodynamic properties. The thermodynamic data obtained in this work may be helpful for exploring the structure function relationship of protocatechualdehyde and p-hydroxybenzaldehyde.

Compounds

#	Formula	Name
1	C7H6O2	4-hydroxybenzaldehyde
2	C7H6O3	3,4-dihydroxybenzaldehyde
3	ClNa	sodium chloride
4	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 3 4	Molar enthalpy of dilution, kJ/mol ; Liquid	Solvent: Molality, mol/kg - 3; Liquid Initial molality of solute, mol/kg; Liquid Final molality of solute, mol/kg; Liquid	Temperature, K; Liquid Pressure, kPa; Liquid	Liquid	Flow calorimetry	70
POMD	1 3 4	Mass density, kg/m3 ; Liquid	Temperature, K; Liquid Solvent: Molality, mol/kg - 3; Liquid Molality, mol/kg - 1; Liquid	Pressure, kPa; Liquid	Liquid	Vibrating tube method	300
POMD	2 3 4	Molar enthalpy of dilution, kJ/mol ; Liquid	Solvent: Molality, mol/kg - 3; Liquid Initial molality of solute, mol/kg; Liquid Final molality of solute, mol/kg; Liquid	Temperature, K; Liquid Pressure, kPa; Liquid	Liquid	Flow calorimetry	84
POMD	2 3 4	Mass density, kg/m3 ; Liquid	Temperature, K; Liquid Solvent: Molality, mol/kg - 3; Liquid Molality, mol/kg - 2; Liquid	Pressure, kPa; Liquid	Liquid	Vibrating tube method	300
POMD	1 4	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	Flow calorimetry	10
POMD	3 4	Mass density, kg/m3 ; Liquid	Temperature, K; Liquid Molality, mol/kg - 3; Liquid	Pressure, kPa; Liquid	Liquid	Vibrating tube method	30
POMD	2 4	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	Flow calorimetry	12

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

Thermodynamic Difference between Protocatechualdehyde and p-Hydroxybenzaldehyde in Aqueous Sodium Chloride Solutions

Xie, J.[Jimin], Liu, M.[Min], Liu, G.[Guiqin], Yuan, L.[Lixia], Li, D.[Dacheng], Fan, Z.[Zhiping], Wang, Z.[Zhengping], Wang, B.[Bingquan], Han, J.[Jun]

ABSTRACT