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Composition of dry air
| Constituent | Abundance (mole fraction) | Molecular Weight |
|---|---|---|
| Nitrogen (N2) | 0.78102 | 28.0134 |
| Oxygen (O2) | .20946 | 31.9988 |
| Carbon Dioxide (CO2) | .00033 | 44.0098 |
| Argon (A) | .00916 | 39.948 |
| Neon (Ne) | .00001818 | 20.179 |
| Helium (He) | .00000524 | 4.00260 |
| Krypton (Kr) | .00000114 | 83.80 |
| Xenon (Xe) | .000000087 | 131.30 |
| Hydrogen (H2) | .0000005 | 2.0158 |
| Methane (CH4) | .0000015 | 16.0426 |
| Nitrous Oxide (N2O) | .0000003 | 44.0128 |
