Several gases are a part of air: hydrogen, oxygen and nitrogen, and the last contains about 80%. Also there is a small amount of water vapor. Nitrogen plays an important role in many processes of the nature.
Physical properties of nitrogen
Nitrogen - one of the major chemical elements in the nature. He is present at all living organisms and participates in reactions between cages and synthesis of proteins. In its earth crust not really there is a lot of, in comparison with the atmosphere. Nitrogen forms many minerals and also the substances having important industrial value. Among them: sodium (Chilean) and potassium (Indian) saltpeter. These substances are used as fertilizers.
Nitrogen in a free state meets in the form of diatomic molecules. Energy of dissociation of these molecules is quite high. At 3000 degrees Celsius dissociates only 0.1% of total. The molecule of nitrogen consists of two stable isotopes with atomic masses 14 and 15 respectively. The first of them turns into radioactive isotope of carbon in an upper atmosphere under the influence of space radiation.
Chemical properties of nitrogen
The majority of reactions of chemical elements with nitrogen takes place at high temperatures. Only active metals, such as lithium, potassium, magnesium are capable to react with nitrogen at low temperatures. Nitrogen reacts with oxygen in the atmosphere when passing electric discharge. At the same time NO nitrogen oxide which then when cooling can be oxidized to NO ₂ is formed. In vitro NO can be received from mix of nitrogen and oxygen under the influence of powerful ionizing radiation. Nitrogen directly does not react with halogens (chlorine, fluorine, iodine, bromine). But fluoride of nitrogen can be received from reaction of ammonia with fluorine. Similar connections are usually unstable (an exception - fluoric nitrogen). Are more resistant - the oxyhalogenides received at reaction of ammonia with halogens and oxygen. Nitrogen is capable to react with metals. With active metals the reaction goes even at the room temperature, with less active metals the high temperature is necessary. At the same time nitrides are formed. If on nitrogen (with a low pressure) or nitride to work powerful electric discharge, there will be a formation of mix of atoms and molecules of nitrogen. This mix possesses a large supply of energy.
Use of nitrogen
Nitrogen is applied at production of ammonia from which then nitric acid, a set of nitrogen fertilizers and even explosives can be received. Nitrogen in a free state is irreplaceable in metallurgy for receiving complex alloys and synthesis of some substances (nitridokremniyevy ceramics).