Nitrogen dioxide facts for kids

Kids Encyclopedia Facts
Diossido di azoto
Nitrogen dioxide gas in a test tube

Nitrogen dioxide is a chemical compound. Its chemical formula is NO2. It contains nitrogen and oxide ions. The nitrogen is in the +4 oxidation state.

Nitrogen dioxide structure


First bottle has more nitrogen dioxide. Second bottle has more dinitrogen tetroxide

It is a brownish gas. It chokes when it is breathed in. When it is compressed, two of the molecules bond, making dinitrogen tetroxide. It also makes the dinitrogen tetroxide when it is cooled. It is an oxidizing agent. It turns back into nitric oxide and oxygen when it is heated. It reacts with iodides to make nitrites and iodine. It is what makes nitric acid yellow.


Nitrogen dioxide is normally made by oxidation of nitric oxide by oxygen in air. It can also be made by heating some nitrates. It can be made by reacting concentrated nitric acid with copper or tin.


It is used to make nitric acid by dissolving it in water. Nitric oxide is also released.


Nitrogen dioxide is very toxic. It is also released by some cars, polluting the atmosphere. It has a bad odor. It makes mushroom clouds (clouds produced when a nuclear weapon explodes) reddish-brown. It can stop the nose from smelling, making the person unaware that they are breathing toxic fumes.

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Nitrogen dioxide Facts for Kids. Kiddle Encyclopedia.