Nitrogen

Nitrogen is a colorless gaseous element found free in air. It constitutes part of the atmosphere, forming about four fifths of common air. Chemically, Nitrogen is almost inert , but forms by combination nitric acid and ammonia.Nitrogen is used as a diluent for medicinal gases. Pharmaceutically Nitrogen is employed to replace air in the containers of substances which would be adversely affected by air oxidation. Therefore Nitrogen is used with fixed oils, certain vitamin preparations and a variety of injectable products. Nitrogen is also used as a propellent. Nitrogen is also important biologically, being a constituent of protein ad nucleic acid, thus present in all living cells. Nitrogen is used to replace the air in pharmaceutical preparations.