Nitric oxide

Nitric oxide also known as nitrogen monoxide is a chemical compound. It contains nitrogen in its +2 oxidation state. It contains nitrogen and oxide ions. Its chemical formula is often given as ·N=O.
Properties.
It is a colorless gas. It is easily oxidized to nitrogen dioxide by air. It can react with a mixture of air and water to make nitrous acid. It glows when reacted with ozone.
Preparation.
It is made by reacting ammonia with oxygen with a catalyst. It is also made in lightning. It can be made in small amounts by reacting copper with nitric acid. It can also be made by reducing nitrous acid with compounds such as iron(II) sulfate.
Uses.
Nitric oxide is used in making nitric acid from ammonia. Ammonia is reacted with air to make nitric oxide, and the nitric oxide is oxidized by air to make nitrogen dioxide. The nitrogen dioxide is dissolved in water to make nitric acid and more nitric oxide.
It is also used as a stimulant in the human body. It has many actions in the human body that are being studied.
Safety.
Nitric oxide is toxic when breathed in. It also easily is oxidized to nitrogen dioxide, a toxic brown choking substance.