Propane - CH3CH2CH3
CAS#: 74-98-6
Molar mass: 44.096 kg/kmol
Triple point temperature: 85.53 K
Normal boiling point temperature: 231.04 K
Critical point temperature: 369.89 K
Critical point pressure: 4.2512 MPa
Critical point density: 220.48 kg/m³
Gas phase dipole at NBP: 0.084 debye
Acentric factor: 0.1521
Equation of State
Equation type: Helmholtz energy
Limits: 85.53 K to 625.0 K, 1000.0 MPa, 908.37 kg/m³
Lemmon, E.W., McLinden, M.O., Wagner, W. to be submitted to J. Phys. Chem. Ref. Data, 2007.
Below 350 K, the uncertainties in density are 0.01% in the liquid phase and 0.03% in the vapor phase (including saturated states for both phases). The liquid phase value also applies at temperatures greater than 350 K (to about 500 K) at pressures greater than 10 MPa. In the extended critical region, the uncertainties increase to 0.1% in density, except very near the critical point where the uncertainties in density increase rapidly as the critical point is approached. However, in this same region, the uncertainty in pressure calculated from density and temperature is 0.04%, even at the critical point.
The uncertainties in the speed of sound are 0.01% in the vapor phase at pressures up to 1 MPa, 0.03% in the liquid phase between 260 and 420 K and 0.1% in the liquid phase at temperatures below 260 K. The uncertainty in vapor pressure is 0.02% above 180 K, 0.1% between 120 and 180 K, and increases steadily below 120 K. Below 115 K, vapor pressures are less than 1 Pa and uncertainty values might be as low as 3% at the triple point. Uncertainties in heat capacities are 0.5% in the liquid phase, 0.2% in the vapor phase, and higher in the supercritical region.
Viscosity
Limits: 85.47 K to 600.0 K, 100.0 MPa, 881.91 kg/m³
Vogel, E., Kuechenmeister, C., Bich, E., and Laesecke, A., "Reference Correlation of the Viscosity of Propane," J. Phys. Chem. Ref. Data, 27(5):947-970, 1998.
The uncertainty in viscosity varies from 0.4% in the dilute gas between room temperature and 600 K, to about 2.5% from 100 to 475 K up to about 30 MPa, and to about 4% outside this range.
Thermal Conductivity
Limits: 85.47 K to 600.0 K, 100.0 MPa, 881.91 kg/m³
Marsh, K., Perkins, R., and Ramires, M.L.V., "Measurement and Correlation of the Thermal Conductivity of Propane from 86 to 600 K at Pressures to 70 MPa," J. Chem. Eng. Data, 47(4):932-940, 2002.
Uncertainty in thermal conductivity is 3%, except in the critical region and dilute gas which have an uncertainty of 5%.
Surface Tension
Limits: 85.47 K to 369.85 K
Baidakov, V.G. and Sulla, I.I. "Surface tension of propane and isobutane at near-critical temperatures," Russian Journal of Physical Chemistry, 59:551-554, 1985.
Melting Line
Limits: 85.48 K to 2000.0 K
Reeves, L.E., Scott, G.J., Babb, S.E., Jr. "Melting curves of pressure-transmitting fluids," J. Chem. Phys., 40(12):3662-6, 1964.
Coefficients have been modified (2004)