Thermodynamic properties of n-pentane

Specific volumes and isobaric heat capacity measurements are reported for n-pentane. The measurements were made in the liquid and vapor phases at temperatures ranging from the triple point (173 K) to the onset of dissociation temperature (700 K) and pressures up to 100 MPa including a wide region around the critical point. We are able to fit our data, as well as those of a number of other authors, to a single equation of state with 30 constants. This equation yields the density of n-pentane in the temperature range from 280 to 650 K at pressures up to 80 MPa and the caloric properties up to 500 K. Additional experimental investigations of the thermodynamic properties are required for temperatures above 500 K. Interpolating equations for the caloric properties on the saturated line and in the critical region are also presented.