ABSTRACT

Densities and speeds of ultrasound in binary mixtures of dibromomethane with heptane have been measured within the temperature range from 288.15 K to 318.15 K. From the experimental data, the thermodynamic excess volume, molar isobaric expansion, molar isentropic compression, and ultrasonic speed were calculated. The excess volume and excess isentropic compression have opposite signs, whereas the excess isobaric expansion is an S-shaped function of the mole fraction. An explanation was suggested to account for the excesses in terms of intermolecular interactions. It involved energetic and steric factors. Moreover, it was shown that the positive excess sound speed results almost entirely from the negative excess compression.

Compounds

#	Formula	Name
1	C7H16	heptane
2	CH2Br2	dibromomethane

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	Refractive index (Na D-line) ; Liquid	Temperature, K; Liquid Pressure, kPa; Liquid		Liquid	Standard Abbe refractometry	1
POMD	2	Refractive index (Na D-line) ; Liquid	Temperature, K; Liquid Pressure, kPa; Liquid		Liquid	Standard Abbe refractometry	1
POMD	2 1	Speed of sound, m/s ; Liquid	Mole fraction - 2; Liquid Temperature, K; Liquid	Pressure, kPa; Liquid	Liquid	Pulse-echo method	55
POMD	2 1	Mass density, kg/m3 ; Liquid	Mole fraction - 2; Liquid Temperature, K; Liquid	Pressure, kPa; Liquid	Liquid	Vibrating tube method	91

Thermodynamics Research Center / ThermoML | International Journal of Thermophysics

Thermodynamic and Acoustic Properties of Mixtures of Dibromomethane + Heptane

Przybyla, A.[Anna], Chorazewski, M.[Miroslaw], Zorebski, E.[Edward], Marczak, W.[Wojciech]

ABSTRACT