Behavior of Isobaric Heat Capacity of Pentafluoroethane in the Gas Phase

Abstract

The isobaric specific heat capacity cp of gaseous pentafluoroethane was measured and the behavior was presented. With a flow calorimeter, 29 cp data of pentafluoroethane were measured at temperatures T from (303 to 343) K and at pressures p from (0.5 to 2.4) MPa. Some of them were measured in the immediate vicinity of the saturation curve. The expanded uncertainties (k = 2) of the temperature measurements U(T) and the pressure measurements U(p) are estimated to be below 50 mK and 11 kPa, respectively. That for cp measurements Uc(cp) is assessed to extend from (14 to 60) J·kg–1·K–1. Then, the cp measurements including the previous 12 measurements were compared with some available equations of state. Using these confirmed data, the cp behaviors of gaseous pentafluoroethane were presented in a cp–p diagram.