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Physical Properties for Hydrogen

Formula H2
Molecular Weight (lb/mol) 2.02
Critical Temp. (°F) -400.0
Critical Pressure (psia) 187.5
Boiling Point (°F) -423.0
Melting Point (°F) -434.5
Psat @ 70°F (psia) (note 1)
Liquid Density @ 70°F (lb/ft3) (note 1)
Gas Density @ 70°F 1 atm (lb/ft3) 0.0052
Specific Volume @ 70°F 1 atm (ft3/lb) 191.90
Specific Gravity 0.069
Specific Heat @ 70°F (Btu/lbmol-°F) 6.87

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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