Air
Air is a colourless, odourless, tasteless and non-toxic mixture of gases that surround the Earth. It is non-flammable, but does support combustion. The composition varies with the altitude at which the sample is taken, for example; the combination at sea level is approximately 78.09% nitrogen, 20.95% oxygen, 0.93% argon, 0.039% carbon dioxide, and small amounts of other gases.
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Properties |
U.S. Units |
S.I. Units |
|
Chemical formula |
Air |
Air |
|
Molecular weight |
28.975 |
28.975 |
|
Density of the gas at 70°F (21.1°C) and 1atm |
0.07493 lb/ft3 |
1.2000 kg/m3 |
|
Specific gravity of the gas at 70°F (21.1°C) and 1 atm (air=1) |
1.00 |
1.00 |
|
Specific volume of the gas at 70°F (21.1°C) and 1 atm |
13.346 ft3/lb |
0.8333 m3/kg |
|
Density of the liquid at boiling point and 1atm |
54.56 lb/ft3 |
875.0 kg/m3 |
|
Boiling point at 1 atm |
-317.8°F |
-194.3°C |
|
Freezing point at 1atm |
-357.2°F |
-216.2°C |
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Critical temperature |
-221.1°F |
-140.6°C |
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Critical pressure |
547psia |
37.7 bar |
|
Critical density |
21.9 lb/ft3 |
351.6 kg/m3 |
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Solubility in water vol/vol at 32°F(0°C) |
0.0292 |
0.0292 |
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Industry |
Usage |
|
Diving |
Used in Diving Air Compressor, as a breathing gas |
|
Construction |
Pneumatic drills |
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Labs & Analysis |
Air is used to calibrate environmental emission monitoring, industrial hygiene monitors and trace impurity analyzers and as balance gas for some calibration mixtures. |
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Oil & Gas |
Air or oxygen enriched air is used as oxidizing compound to burn sulfur to sulfur dioxide |