Measurements of the isobaric specific heat capacity for 1,1,1-trifluoroethane (R143a), pentafluoroethane (R125), and difluoromethane (R32) in the liquid phase

Measurements of the isobaric specific heat capacity for the hydrocarbons 1,1,1-trifluoroethane (R143a), pentafluoroethane (R125), and difluoromethane (R32) were carried out in the liquid phase at a pressure of 5 MPa by using a batch type calorimeter equipped with a metal bellows. Ten data points of the isobaric specific heat capacity for R143a, 11 data points for R125, and seven data points for R32 were obtained in the temperature range from (310 to 350) K and at a pressure of 5 MPa. The experimental uncertainties are estimated to be 5 mK for temperature, 3 kPa for pressure, and 5.2 % for isobaric specific heat capacity. The present results were compared with the literature data and the values calculated from the equation of state. The correlations of the isobaric specific heat capacity were formulated as a function of temperature at a pressure of 5 MPa. Maximum deviations of the present results from correlations were 1.4 % for R143a, 1.5 % for R125, and 0.9 % for R32, respectively.