This cartoon shows some of the gases in Earth's troposphere. There is more nitrogen (N2) than anything else. There is also a lot of oxygen (O2). The cartoon also shows carbon dioxide (CO2), water vapor (H2O), methane (CH4), sulfur dioxide (SO2), and carbon monoxide (CO).
Click on image for full size
Image courtesy UCAR, modified by Windows to the Universe staff (Randy Russell).

Chemicals in Earth's Atmosphere

Most of the gas in Earth's atmosphere is nitrogen. About 4/5ths of the air is nitrogen. What about the other 1/5th? Almost all of it is oxygen, the stuff in the air we need to breathe. There are also very small amounts of a bunch of other chemicals.

Have you heard of greenhouse gases? They are kinds of gases that trap the heat from sunlight in our atmosphere. Earth would be very cold if we didn't have any greenhouse gases. Carbon dioxide and methane are two very important greenhouse gases.

Some of the chemicals in the air are different in the different layers of Earth's atmosphere.

Some chemicals move in cycles between the atmosphere, living creatures, and the oceans. The Carbon Cycle and the Nitrogen Cycles are two important cycles that change the chemistry of the atmosphere.

Some of the chemicals in the air come from pollution. When we burn coal in a factory or gasoline in our cars, we make air pollution. Coal and oil have sulfur in them. When they burn, they make chemicals called sulfur oxides. These can turn into sulfuric acid when they mix with water droplets in the air. These droplets of acid can fall to the ground as acid rain. Cars and trucks also give off chemicals called nitrogen oxides. Nitrogen oxides combine with other chemicals to make smog. They also help make nitric acid, which is another acid in acid rain.

Last modified July 13, 2009 by Randy Russell.

You might also be interested in:

Cool It! Game

Check out our online store - minerals, fossils, books, activities, jewelry, and household items!...more

Nitrogen

There is more nitrogen gas in the air than any other kind of gas. About 4/5ths of Earth's atmosphere is nitrogen gas! A molecule of nitrogen gas is made up of two nitrogen atoms. There are other molecules...more

Oxygen

Oxygen (O2) is a kind of gas. A lot of the air you breathe is oxygen. That's a good thing, since we need oxygen to stay alive! About 4/5ths of the air in Earth's atmosphere is nitrogen (N2). Almost all...more

Earth's Greenhouse Gases

Even though only a tiny amount of the gases in Earth’s atmosphere are greenhouse gases, they have a huge effect on climate. There are several different types of greenhouse gases. The major ones are carbon...more

Carbon Dioxide - CO2

Carbon dioxide (CO2) is a kind of gas. There isn't that much carbon dioxide in Earth's atmosphere, but it is still very important. Carbon dioxide is a greenhouse gas. That means it helps trap heat coming...more

Methane - CH4

Methane is a kind of gas. There is a small amount of methane in the air you breathe. A methane molecule has carbon and hydrogen atoms in it. Methane is a greenhouse gas. That means it helps make Earth...more

Atmospheric Chemistry

When you think of chemistry, do you think about mixing colored liquids in test tubes and maybe making an explosion... or at least a nice puff of smoke? Did you know that a lot of chemistry happens in Earth's...more

Air Pollution

What do smog, acid rain, carbon monoxide, fossil fuel exhausts, and tropospheric ozone have in common? They are all examples of air pollution. Air pollution is not new. As far back as the 13 th century,...more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA