Thermodynamic Properties of HFC-227ea

The density and speed of sound in gaseous and liquid 1,1,1,2,3,3,3-heptafluoropropane (HFC-227ea) have been studied by a c-attenuation technique, an ultrasonic iInterferometer, and an isochoric piezometer method over the temperature range of 273 to 383 K at pressures up to 3.5 MPa. The purity of the samples used throughout the measurements are 99.99 mol%. The pressures of the saturated vapor were measured over the same temperature range. The experimental uncertainties of the temperature, pressure, density, and speed of sound measurements were estimated to be within ±20 mK, ±1.5 kPa, ±0.2%, and ±(0.15–0.2)%, respectively. On the basis of the obtained data, the isobaric molar heat capacity of HFC-227ea was calculated for the ideal-gas state.