Ka. Gillis, THERMODYNAMIC PROPERTIES OF 7 GASEOUS HALOGENATED HYDROCARBONS FROM ACOUSTIC MEASUREMENTS - CHCLFCF3, CHF2CF3, CF3CH3, CHF2CH3, CF3CHFCHF2,CF3CH2CF3, AND CHF2CF2CH2F, International journal of thermophysics, 18(1), 1997, pp. 73-135
Measurements of the speed of sound in seven halogenated hydrocarbons a
re presented. The compounds in this study are l-chloro-l,2,2,2-tetrafl
uoroethane (CHClFCF3, or HCFC-124), pentafluoroethane (CHF2CF3 or HFC-
125), 1,1,1-trifluoroethane (CF,CH, or HFC-143a), 1,1-difluoroethane (
CHF2CH3, or HFC-152a), 1,1,1,2,3,3-hexafluoropropane (CF3CHFCHF2 or HF
C-236ea), 1,1,1,3,3,3-hexafluoropropane (CF3CH2CF3 or HFC-236fa), and
1,1,2,2,3-pentafluoropropane (CHF2CF2CH2F or HFC-245ca). The measureme
nts were performed with a cylindrical resonator at temperatures betwee
n 240 and 400 K and at pressures up to 1.0 MPa. Ideal-gas heat capacit
ies and acoustic virial coefficients were directly deduced from the da
ta. The ideal-gas heat capacity of HFC-125 from this work differs from
spectroscopic calculations by less than 0.2% over the measurement ran
ge. The coefficients for virial equations of state were obtained from
the acoustic data and hard-core square-well intermolecular potentials.
Gas densities that were calculated from the virial equations of state
for HCFC-124 and HFC-125 differ from independent density measurements
by at most 0.15%, for the ranges of temperature and pressure over whi
ch both acoustic and Burnett data exist. The uncertainties in the deri
ved properties for the other five compounds are comparable to those fo
r HCFC-124 and HFC-125.