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Physical Properties for Helium

Formula He
Molecular Weight (lb/mol) 4.00
Critical Temp. (°F) -450.3
Critical Pressure (psia) 33.0
Boiling Point (°F) -452.1
Melting Point (°F) --
Psat @ 70°F (psia) (note 1)
Liquid Density @ 70°F (lb/ft3) (note 1)
Gas Density @ 70°F 1 atm (lb/ft3) 0.0103
Specific Volume @ 70°F 1 atm (ft3/lb) 96.65
Specific Gravity 0.138
Specific Heat @ 70°F (Btu/lbmol-°F) 4.97

1 = Signifies at 70°F, the compound is above its critical temperature.
2 = Signifies that at 70°F, the compound is below the normal boiling point and only the equilibrium vapor is present at 1 atmosphere.

Gas Physical Properties

Gas Fast Facts


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