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Characteristics
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- Colorless
- Odorless
- Tasteless
- Nonirritating
- Nontoxic
- It rises and dissipates quickly
- No environmental impact—it does not produce acid rain or any emissions
- Flammable
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Properties
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Auto ignition temperature |
520oC (968oF) |
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Boiling point (1 atm) |
-252.7oC (-423.0oF) |
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Density |
0.08342 kg/m3 |
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Diffusivity |
1.697 m2/hr |
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Flame temperature |
2318oC (4202.4oF) |
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Flammable range |
4-74% by vol in air |
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Freezing/melting point |
-259.2oC (-434.5oF) |
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Heat of combustion by mass |
28670 kcal/kg |
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Ignition energy |
0.02 milli joules |
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Molecular weight |
2.016 |
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Specific gravity |
0.0696 (air = 1) |
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Specific volume |
11.99 m3/kg (191.98 scf/lb) |
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0.157 kcal/m hr oK |
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Viscosity |
33.84 x 10-3 kg/m hr |
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Volumetric energy density |
57.8 kcal/kg mole |
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Hydrogen Energy site — Hydrogen Basics
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