Nitrogen oxides - Nitric oxide (NO) & Nitrogen dioxide (NO2)

Here are four different ways chemists use to show a molecule of nitric oxide. In the colored molecule models, nitrogen is blue and oxygen is red.
Click on image for full size (19 Kb GIF)
Windows to the Universe original artwork by Randy Russell.
Here are four different ways chemists use to show a molecule of nitrogen dioxide.
Click on image for full size (26 Kb GIF)
Windows to the Universe original artwork by Randy Russell.

Nitric oxide (NO) and nitrogen dioxide (NO2) are the names of two kinds of gases. Together, they are called nitrogen oxides. Nitrogen oxide molecules have nitrogen and oxygen atoms in them.

Nitrogen oxides help cause some kinds of air pollution. Nitrogen dioxide combines with other chemicals to make smog. It also combines with water droplets in the air to make nitric acid. Nitric acid is one of the kinds of acid in acid rain

Where do nitrogen oxides come from? Volcanoes and lightning make some of the nitrogen oxides in Earth's atmosphere. Humans make lots of nitrogen oxides, too. When fuel burns, nitrogen in the air combines with oxygen to make nitrogen oxides. The engines of cars, trucks, and buses make lots of nitrogen oxides.

Nitrogen oxides are not all bad. Humans use nitric oxide to make nitric acid. Nitric acid is used to make fertilizer and some kinds of explosives!

Nitric acid

PAN - Peroxyacytyl nitrate


Last modified February 16, 2006 by Randy Russell.

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