Appendix E: Critical Properties of Selected Fluids
Table E1: Critical Constants of Selected Fluids
Substance
|
Formula
|
Molecular Mass (g/mol) |
Temperature (K) |
Pressure (MPa) |
Specific Volume (m3/kg) |
Water |
H2O |
18.015 |
647.1 |
22.06 |
0.003110 |
Ammonia |
NH3 |
17.031 |
405.4 |
11.34 |
0.004444 |
Nitrogen |
N2 |
28.013 |
126.2 |
3.40 |
0.003192 |
Hydrogen |
H2 |
2.0160 |
33.1 |
1.30 |
0.031986 |
Oxygen |
O2 |
31.999 |
154.6 |
5.04 |
0.002293 |
Carbon Dioxide |
CO2 |
44.010 |
304.1 |
7.38 |
0.002139 |
Methane |
CH4 |
16.043 |
190.6 |
4.60 |
0.006148 |
Ethane |
C2H6 |
30.069 |
305.3 |
4.87 |
0.004841 |
Propane |
C3H8 |
44.096 |
369.8 |
4.25 |
0.004536 |
Refrigerant, R12 |
CCl2F2 |
120.914 |
385.1 |
4.14 |
0.001770 |
Refrigerant, R22 |
CHClF2 |
86.468 |
369.3 |
4.99 |
0.001908 |
Refrigerant, R134a |
CF3CH2F |
102.03 |
374.2 |
4.06 |
0.001954 |
Source: Eric W. Lemmon, Mark O. McLinden and Daniel G. Friend, “Thermophysical Properties of Fluid Systems” in NIST Chemistry WebBook, NIST Standard Reference Database Number 69, Eds. P.J. Linstrom and W.G. Mallard, National Institute of Standards and Technology, Gaithersburg MD, 20899, https://doi.org/10.18434/T4D303, (retrieved May 2021).