Experimental Critical Constants, Vapor Pressures, and Vapor and Liquid Densities for Pentafluoroethane (R-125)

This paper presents measurements of vapor pressure from 220 K to 338 K, liquid density from 180 K to 350 K and up to 70 MPa and vapor density from 310 K to 480 K and up to 12 MPa for pentafluoroethane (R-125). Extrapolating the observed vapor pressures to the measured critical temperature (339.41 ± 0.01) K provides a critical pressure of (3.6391 ± 0.002) MPa. Using these values with the law of rectilinear diameters indicates a critical density of (4768 ± 7) mol·m^-3. Correlations provide values which agree with the measured values for the vapor densities within ± 0.05%, the liquid densities within ±0.1%, and the vapor pressures within ±0.05%. The results are compared with values from the literature.