Specific Heats of Oxygen at Coexistence

Molar Heat Capacity (Cv) for Saturated and Compressed Liquid and Vapor Nitrogen from 65 to 300 K at Pressures to 35 MPa

Molar heat capacities at constant volume (Cv ,) for nitrogen have been measured with an automated adiabatic calorimeter. The temperatures ranged from 65 to 300 K, while pressures were as high as 35 MPa. Calorimetric data were obtained for a total of 276 state conditions on 14 isochores. Extensive results which were obtained in the saturated liquid region (Cv(2) and Cσ ) demonstrate the internal consistency of the Cv (ρ,T) data and also show satisfactory agreement with published heat capacity data. The overall uncertainty of the Cv values ranges from 2% in the vapor to 0.5% in the liquid.

Specific Heats of Saturated and Compressed Liquid Propane

Experimental specific heats for saturated liquid propane, along the coexistence path, have been determined from the triple-point temperature (~ 85 K) to 289 K. Specific heats for the compressed liquid at constant molal volume have been determined along isochores at nine different densities ranging from near the triple-point liquid density to about twice the critical-point density (at pressures up to 300 bar). Comparisons with previous experimental- and/or derived-data show agreement within combined uncertainties of about three percent.

Thermophysical Properties of Methane: Orthobaric Densities and Some Thermal Properties

For use in the computation of thermodynamic functions, analytical descriptions are given for the following properties: the orthobaric densities and saturation temperatures; the heats of vaporization; the specific heats of saturated liquid; and the thermodynamic functions for ideal gas states.

Specific Heats, Cv, of Compressed Liquid and Gaseous Fluorine

Experimental specific heats at constant volume for compressed gaseous and liquid fluorine are reported from 80 K to 300 K at pressures to about 23 MN/m2.

Specific Heats of Fluorine at Coexistence

Experimental specific heats of fluorine at constant total volume are reported for the two-phase, liquid-vapor system from triple- to the critical point. Specific heats of liquid along the coexistence path are derived by use of PVT data for the two-phase system, and are represented by a formula to facilitate computations of thermodynamic properties.

Nonanalytic Vapor Pressure Equation With Data for Nitrogen and Oxygen

The specific heat of a two phase liquid-vapor system at constant volume apparently increases without limit at temperatures approaching the critical point, suggesting (via a thermodynamic relation) that the vapor pressure derivative d 2 P/dT 2 may behave similarly. This nonanalytic behavior at the critical point is used in the present vapor pressure formula to gain simplicity and accuracy, as seen by use of data for nitrogen and oxygen.