Isochoric p-rho-T measurements for 2,2-dichloro-1,1,1-trifluoroethane (R123) at temperatures from 176 to 380 K and 1-chloro-1,2,2,2-tetrafluoroethane(R124) from 104 to 400 K at pressures to 35 MPa

The p-p-T relationships were measured for 2,2-djchloro-1,1,1-trifluoroethan e (R123) and 1-chloro-1,2,2,2-tetrafluoroethane (R124) by an isochoric meth od with gravimetric determinations of the amount of substance. Temperatures ranged from 176 to 380 K For R123 and from 104 to 400 K for R124, while pr essures extended lip to 35 MPa. Measurements were conducted on compressed l iquid samples. Mort published p-p-T data are in good agreement with this st udy. The uncertainty is 0.03 K for temperature and 0.01% for pressure at p > 3 MPa and 0.05 % at p < 3 MPa. The principal source of uncertainty is the cell volume (similar to 28.5 cm(3)), with a standard uncertainty of 0.003 cm3. When all components of experimental uncertainty are considered, the ex panded relative uncertainty (with a coverage factor k = 2 and, thus, a 2-SD estimate) of the density measurements is estimated to be 0.05%.