Helium - Thermophysical Properties
Chemical, Physical and Thermal Properties of Helium - He.
Chemical, physical and thermal properties of Helium - He :
(values at 25 oC (77 oF, 298 K) and atmospheric pressure)
| Molecular Weight | 4.0026 |
| Specific Gravity, air = 1 | 0.138 |
| Specific Volume (ft3/lb, m3/kg) | 97.86, 6.11 |
| Density of liquid at atmospheric pressure (lb/ft3, kg/m3) | 7.80, 125 |
| Absolute Viscosity (lbm/ft s, centipoises) | 13.4×10-6, 0.02 |
| Sound velocity in gas (m/s) | 1015 |
| Specific Heat - cp - (Btu/lb oF or cal/g oC, J/kgK) | 1.24, 5188 |
| Specific Heat Ratio - cp/cv | 1.66 |
| Gas constant - R - (ft lb/lb oR, J/kg oC) | 386, 2077 |
| Thermal Conductivity (Btu/hr ft oF, W/moC) | 0.086, 0.149 |
| Boiling Point - saturation pressure 14.7 psia and 760 mm Hg - (oF,o K) | -452, 4.22 |
| Latent Heat of Evaporation at boiling point (Btu/lb, J/kg) | 10.0, 23300 |
| Critical Temperature (oF,o K) | -450.3, 5.2 |
| Critical Pressure (psia, MN/m2) | 33.22, - |
| Critical Volume (ft3/lb, m3/kg) | 0.231, 0.0144 |
| Flammable | no |
Follow the links below to get values for the listed properties of helium at varying pressure and temperature :
See also more about atmospheric pressure, and STP - Standard Temperature and Pressure & NTP - Normal Temperature and Pressure,
as well as Thermophysical properties of: Acetone, Acetylene, Air, Ammonia, Argon, Benzene, Butane, Carbon dioxide, Carbon monoxide, Ethane, Ethanol, Ethylene, Hydrogen, Hydrogen sulfide, Methane, Methanol, Nitrogen, Oxygen, Pentane, Propane, Toluene, Water and Heavy water, D2O .
