Measurements of the specific heats, Cs, and Cv, of dense gaseous and liquid ethane

Abstract

The spec ific heat s of saturated liquid ethane, Ca, have been measured a t 106 temperatures in the t cmpera ture range 93 to 301 K . The specific heats at constant volume, C" have bee n meas ured at 19 densities ran gin g from 0.2 to 3.1 times the critical dens ity, a t t emperatures betwee n 91 a nd 330 IC, with pressures to 33 MPa, at 200 PVT states in a ll. The uncertainty of m ost of the m easurements is estimated t o be less than 2.0 percent. As the critical point is approached the uncertainty ri ses t o about 5.0 percent . The m easurements were perform ed to provide inpu t da ta for accur ate calculations o f the thermod yn amic properties for etha ne. They are believed to be the most comprehensive specific heat measurements available for the liquid and vapor states o f ethane.