Gas type | Chem. Formula | Volume % | Partial pressure [hPa] |
---|---|---|---|
Nitrogen | N2 | 78.09 | 780.9 |
Oxygen | O2 | 20.95 | 209.5 |
Water vapor | H2O | < 2.3 | < 23.3 |
Argon | Ar | 9.3·10 -1 | 9.3 |
Carbon dioxide | CO2 | 3.0·10-2 | 3.0·10-1 |
Neon | Ne | 1.8·10 -3 | 1.8·10-2 |
Hydrogen | H2 | < 1·10-3 | < 1·10-2 |
Helium | He | 5.0·10 -4 | 5.0·10-3 |
Methan | CH4 | 2.0·10-4 | 2.0·10-3 |
Krypton | Kr | 1.1·10 -4 | 1.1·10-3 |
Carbon monoxide | CO | < 1.6·10-5 | < 1.6·10-4 |
Xenon | Xe | 9.0·10 -6 | 9.0 . 10-5 |
Nitrous oxide | N2O | 5.0·10 -6 | 5.0·10-5 |
Ammonia | NH3 | 2.6·10-6 | 2.6·10-5 |
Ozone | O3 | 2.0·10-6 | 2.0·10-5 |
Hydrogen peroxide | H2O 2 | 4.0·10-8 | 4.0·10-7 |
Iodine | I2 | 3.5·10-9 | 3.5·10-8 |
Radon | Rn | 7.0·10 -18 | 7.0·10-17 |
Pressure range | Pressure hPa | Pressure Pa | Number density per cm3 | Mean free path in m |
---|---|---|---|---|
Atmospheric pressure | 1,013.25 | 101,325 | 2.7·1019 | 6.8·10-8 |
Low vacuum (LV) | 300…1 | 30,000…100 | 1019…1016 | 10-8…10-4 |
Medium vacuum (MV) | 1…10-3 | 100…10-1 | 1016 …1013 | 10-4…10-1 |
High vacuum (HV) | 10-3…10-8 | 10-1…10-6 | 1013…108 | 10-1…104 |
Ultra-high vacuum (UHV) | 10-8…10-11 | 10-6…10-9 | 108…105 | 104…107 |
Extremely high vacuum (XHV) | <10-11 | <10-9 | <105 | >107 |
Pa | bar | hPa | µbar | Torr | micron | atm | at | mm WS | psi | psf | |
---|---|---|---|---|---|---|---|---|---|---|---|
Pa | 1 | 1·10-5 | 1·10-2 | 10 | 7.5·10-3 | 7.5 | 9.87·10-6 | 1.02·10-5 | 0.102 | 1.45·10-4 | 2.09·10-2 |
bar | 1·105 | 1 | 1·103 | 1·106 | 750 | 7.5·105 | 0.987 | 1.02 | 1.02·104 | 14.5 | 2.09·103 |
hPa | 100 | 1·10-3 | 1 | 1,000 | 0.75 | 750 | 9.87·10-4 | 1.02·10-3 | 10.2 | 1.45·10-2 | 2.09 |
µbar | 0.1 | 1·10-6 | 1·10-3 | 1 | 7.5·10-4 | 0.75 | 9.87·10-7 | 1.02·10-6 | 1.02·10-6 | 1.45·10-5 | 2.09·10-3 |
Torr | 1.33·102 | 1.33·10-3 | 1.33 | 1,330 | 1 | 1,000 | 1.32·10-3 | 1.36·10-3 | 13.6 | 1.93·10-2 | 2.78 |
micron | 0.133 | 1.33·10-6 | 1.33·10-3 | 1.33 | 1·10-3 | 1 | 1.32·10-6 | 1.36·10-6 | 1.36·10-2 | 1.93·10-5 | 2.78·10-3 |
atm | 1.01·105 | 1.013 | 1,013 | 1.01·106 | 760 | 7.6·105 | 1 | 1.03 | 1.03·104 | 14.7 | 2.12·103 |
at | 9.81·104 | 0.981 | 981 | 9.81·105 | 735.6 | 7.36·105 | 0.968 | 1 | 1·10-4 | 14.2 | 2.04·103 |
mm WS | 9.81 | 9.81·10-5 | 9.81·10-2 | 98.1 | 7.36·10-2 | 73.6 | 9.68·10-5 | 1·10-4 | 1 | 1.42·10-3 | 0.204 |
psi | 6.89·103 | 6.89·10-2 | 68.9 | 6.89·104 | 51.71 | 5.17·104 | 6.8·10-2 | 7.02·10-2 | 702 | 1 | 144 |
psf | 47.8 | 4.78·10-4 | 0.478 | 478 | 0.359 | 359 | 4.72·10-4 | 4.87·10-4 | 4.87 | 6.94·10-3 | 1 |
Gas | Chemical Symbol | Molar Mass [g mol-1] | Mean Velocity [m s-1] | Mach Number |
Hydrogen | H2 | 2 | 1,754 | 5.3 |
Helium | He | 4 | 1,245 | 3.7 |
Water vapor | H2O | 18 | 585 | 1.8 |
Nitrogen | N2 | 28 | 470 | 1.4 |
Air | 29 | 464 | 1.4 | |
Argon | Ar | 40 | 394 | 1.2 |
Carbon dioxide | CO2 | 44 | 375 | 1.1 |
Gas | Chemical Symbol | 𝑙¯⋅𝑝 [m hPa] | 𝑙¯⋅𝑝 [m Pa] |
Hydrogen | H2 | 11.5·10-5 | 11.5·10-3 |
Nitrogen | N2 | 5.9·10-5 | 5.9·10-3 |
Oxygen | O2 | 6.5·10-5 | 6.5·10-3 |
Helium | He | 17.5·10-5 | 17.5·10-3 |
Neon | Ne | 12.7·10-5 | 12.7·10-3 |
Argon | Ar | 6.4·10-5 | 6.4·10-3 |
Air | 6.7·10-5 | 6.7·10-3 | |
Krypton | Kr | 4.9·10-5 | 4.9·10-3 |
Xenon | Xe | 3.6·10-5 | 3.6·10-3 |
Mercury | Hg | 3.1·10-5 | 3.1·10-3 |
Water vapor | H2O | 6.8·10-5 | 6.8·10-3 |
Carbon monoxide | CO | 6.8·10-5 | 6.0·10-3 |
Carbon dioxide | CO2 | 4.0·10-5 | 4.0·10-3 |
Hydrogen chloride | HCl | 3.3·10-5 | 3.3·10-3 |
Ammonia | NH3 | 3.2·10-5 | 3.2·10-3 |
Chlorine | Cl2 | 2.1·10-5 | 2.1·10-3 |
Pressure [Pa] | Pressure [hPa] | Mean free path [m] |
1·105 | 1·103 | 5.9·10-8 |
1·104 | 1·102 | 5.9·10-7 |
1·103 | 1·101 | 5.9·10-6 |
1·102 | 1·100 | 5.9·10-5 |
1·101 | 1·10-1 | 5.9·10-4 |
1·100 | 1·10-2 | 5.9·10-3 |
1·10-1 | 1·10-3 | 5.9·10-2 |
1·10-2 | 1·10-4 | 5.9·10-1 |
1·10-3 | 1·10-5 | 5.9·100 |
1·10-4 | 1·10-6 | 5.9·101 |
1·10-5 | 1·10-7 | 5.9·102 |
1·10-6 | 1·10-8 | 5.9·103 |
1·10-7 | 1·10-9 | 5.9·104 |
1·10-8 | 1·10-10 | 5.9·105 |
1·10-9 | 1·10-11 | 5.9·106 |
1·10-10 | 1·10-12 | 5.9·107 |
Viscous flow | Knudsen flow | Molecular flow | |
Low vacuum | Medium vacuum | High / Ultra-high vacuum | |
Pressure range [hPa] | 103…1 | 1…10-3 | < 10-3 bzw. < 10-7 |
Pressure range [Pa] | 105…10 2 | 102…10 -1 | < 10-1 bzw. < 10-5 |
Knudsen number | Kn < 0.01 | 0.01 < Kn < 0.5 | Kn > 0.5 |
Reynolds number | Re < 2,300: laminar Re > 4,000: turbulent | ||
p · d [hPa cm] | p · d > 0.6 | 0.6 > p · d > 0.01 | p · d < 0.01 |
Pa m3 / s = W | mbar l / s | Torr l / s | atm cm3 / s | lusec | sccm | slm | Mol / s | |
Pa m3 / s | 1 | 10 | 7.5 | 9.87 | 7.5·103 | 592 | 0.592 | 4.41·10-4 |
mbar l / s | 0.1 | 1 | 0.75 | 0.987 | 750 | 59.2 | 5.92·10-2 | 4.41·10-5 |
Torr l / s | 0.133 | 1.33 | 1 | 1.32 | 1,000 | 78.9 | 7.89·10-2 | 5.85·10-5 |
atm cm3 / s | 0.101 | 1.01 | 0.76 | 1 | 760 | 59.8 | 5.98·10-2 | 4.45·10-5 |
lusec | 1.33·10-4 | 1.33·10-3 | 10-3 | 1.32·10-3 | 1 | 7.89·10-2 | 7.89·10-5 | 5.86·10-8 |
sccm | 1.69·10-3 | 1.69·10-2 | 1.27·10-2 | 1.67·10-2 | 12.7 | 1 | 10-3 | 7.45·10-7 |
slm | 1.69 | 16.9 | 12.7 | 16.7 | 1.27·104 | 1,000 | 1 | 7.45·10-4 |
Mol / s | 2.27·103 | 2.27·104 | 1.7·104 | 2.24·104 | 1.7·107 | 1.34·106 | 1.34·103 | 1 |