Composition of the Atmosphere
| Constituent | Chemical
Formula | Molecular weight | Percentage
of this constituent in the atmosphere, by volume | Total
mass of this constituent in the whole atmosphere (grams) |
| Nitrogen | N2 | 28.0134 |
78.084 % | 3.866 * 1021 |
| Oxygen | O2 |
31.9988 | 20.948 % |
1.185 * 1021 |
| Argon |
Ar | 39.948 |
0.934 % | 6.59 * 1019 |
| Carbon dioxide | CO2 |
44.00995 | 0.0315 % | 2.45 * 1018 |
| Neon | Ne | 20.183 |
0.001818 % | 6.48 * 1016 |
| Helium | He | 4.0026 |
0.000524 % | 3.71 * 1015 |
| Methane | CH4 |
16.04303 | 0.00015 % |
4.3 x 1015 |
| Hydrogen |
H2 | 2.01594 |
0.00005 % | 1.8 * 1014 |
| Nitrous oxide | N2O |
44.0128 | 0.00003 % |
2.3 * 1015 |
| Carbon monoxide | CO | 28.0106 |
0.000012 % | 5.9 * 1014 |
| Ammonia | NH3 |
17.0306 | 0.000001 % |
3 x 1013 |
| Nitrogen dioxide | NO2 | 46.0055 |
0.0000001 % | 8.1 * 1012 |
| Sulfur dioxide | SO2 |
64.063 | 0.00000002 % |
2.3 * 1012 |
| Hydrogen sulfide | H2S | 34.080 |
0.00000002 % | 1.2 * 1012 |
| Ozone | O3 |
47.9982 | ~ 0.00004 % (variable) | ~ 3.3 * 1015 |
| Water vapor | H2O |
18.01534 | ~ 0.5 % (variable) |
~ 0.017 * 1021 |
| Total atmosphere | - | 28.9644
(average) | - | 5.136
x 1021 |
Adapted from http://ess.geology.ufl.edu/ess/Notes/020-Intro_ESS/atmoscomp.html