It does not burn, does not support combustion, and is only slightly soluble in water. It is relatively inactive chemically, but many of its compounds display marked reactivity. At high temperatures it reacts with some of the other elements to form nitrides. Nitrogen has several oxides. 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.