At high temperatures it reacts with some of the other elements to form nitrides. Nitrogen has several oxides. Nitrogen trioxide, N2O3, is unstable at ordinary temperatures. Nitrogen pentoxide, N2O5, forms nitric acid when dissolved in water. Important compounds of nitrogen include nitric acid , ammonia , many explosives , cyanides , fertilizers , and the proteins .
Many organic compounds contain nitrogen.
Nitrogen for industrial use is produced largely by the fractional distillation of liquid air. Nitrogen is used to some extent for filling light bulbs, in thermometers, and generally anywhere a relatively inert atmosphere is needed. The chief importance of the element lies in its compounds. This is accomplished commercially in several ways. Nitrogen is present in foods and is important in the human diet.