An equation of state for the thermodynamic properties of R143a (1,1,1-trifluoroethane)

Thermodynamic properties of l,l,l-trifluoroethane (RI43al are expressed in terms olʹa 32-term modified Benedict Webb Rubin (M BWR) equation of state. Coefficients arc reported Ibr the MBWR equation and for ancillary equations used to fit the ideal-gas heat capacity, and the coexisting densities and pressure along the saturation boundary. The IVlBWR eoeflqcients were determined from a mnltiproperty fit that used the Ibllowing types of experimental data: PVT: isochoric, isobaric, and satural.ed-liquid heat capacities: second virial coef licients: speed o1" sound and properties at coexistence. The equation of state was optimized to the experimental data from 162 to 346 K and pressures to 35 M Pa with the exception of the critical region. Upon extrapolation to 500 K and 60 M Pa. the equation gives thermodynamically reasonable results. Comparisons between calculated and experimental values are preseInted.