Nitrogen is a chemical element that makes up the majority of the atmosphere, approximately 78.03% by volume and 75.5% by weight. It is an inert gas, except when heated and combined with active metals such as magnesium or lithium. It also forms oxides of nitrogen, when combined with oxygen, and ammonia, when combined with hydrogen.
On the other hand, liquid nitrogen is an inert, colorless, odorless, non-flammable, non-corrosive and extremely cold substance. Although it is not corrosive, nor need special anti-corrosion material, when it is used, either in buildings or in the laboratory, it is necessary to handle it with specialized material that supports low temperatures, since its common temperature is -195.8 ° C. It is very common at industrial level and in laboratories, where it is used as a refrigerant. Although nitrogen is normally used in a gaseous state, when used in liquid form, it is necessary to store and transport it in specialized containers that provide the necessary materials, adequate pressure and that also withstand low temperature.