Molecular
formula
He
UN1006
Gas
UN1951
Refrigerated
liquid
CAS
Number
7440-37-1
Molar mass
Content in dry air
39.948 g/mol
9340.00 ppm
Critical Point
Temperature
Pressure
Density
-122.29 °C
48.98 bar
535.57 kg/m³
Triple Point
Temperature
Pressure
-189.34 °C
6.87E-1 bar
Liquid Phase
Pressure 1.013 bar Boiling point
Latent heat of vaporisation (at boiling point)
Liquid density at boiling
-268.93 °C
20.754 kJ/kg
124.74 kg/m3
Gas Phase
In standard conditions (1.013 bar; 15°C)
1 m3 vol
Gas density at Boiling point
Gas density (0 deg C)
Gas density (15 degC)
Gas density (25 degC)
​Gas/(liquid at boiling point) equivalent(0 degC)
Gas/(liquid at boiling point) equivalent(15 degC)
Gas/(liquid at boiling point) equivalent(25 degC)
1.6903E+00 kg (mass)
5.772 kg/m3
1.7835 kg/cm3
1.6903 kg/cm3
1.3085 kg/cm3
782 vol/vol
825.53 vol/vol
854.24 vol/vol
Heat Capacity
Heat capacity Cp (0 degC)
Heat capacity Cp (15 degC)
Heat capacity Cp (25 degC)
Heat capacity Cv (0 degC)
Heat capacity Cv (15 degC)
Heat capacity Cv (25 degC)
8.2684E-1 kJ(kg.K)
5.2185E-1 kJ(kg.K)
5.2165E-1 kJ(kg.K)
3.1243E-1 kJ(kg.K)
3.1241E-1 kJ(kg.K)
3.1238E-1 kJ(kg.K)
Specific Gravity
Specific gravity
1.38
Solubility
Solubility in water(15 degC)
Solubility in water(25 degC)
3.025 E-5 mol/mol
2.519 E-5 mol/mol
Specific Volume
Specific volume (0 degC)
Specific volume (15 degC)
Specific volume (25 degC)
5.607E-1 m3/kg
5.916E-1 m3/kg
6.122E-1 m3/kg
Thermal conductivity
Thermal conductivity (0 degC)
Thermal conductivity (15 degC)
Thermal conductivity (25 degC)
16.483 mW/(m.K)
17.245 mW/(m.K)
17.746 mW/(m.K)
Viscocity
Viscocity (0 degC)
Viscocity (15 degC)
Viscocity (25 degC)
2.101E-4 Po
2.1987E-4 Po
2.2624E-4 Po