Nitrogen is normally colorless, odorless, tasteless and mostly diatomic non-metal gas. It has five electrons in its outer shell, so it is trivalent in most compounds.

Few Facts about Nitrogen

Atomic Number	7
Atomic Symbol	N
Atomic Weight	14.00674
Electron Configuration	[He]2s22p3
Atomic Radius	71 pm
Melting Point	-210.0°
Boiling Point	-195.79°
Oxidation States	-3, 5

History
Nitrogen was discovered by chemist and physician Daniel Rutherford in the year 1772. He removed oxygen and carbon dioxide from air and proved that the residual gas would not support combustion or living organisms. At the same time, there were other scientists working on the characteristics of nitrogen which include Scheele, Cavendish, Priestley, and others.

Sources
Nitrogen gas (N₂) makes up around 78.1% of the earth's air, by volume. The atmosphere of mars in comparison is only 2.6% nitrogen. From an exhaustible source in our atmosphere, nitrogen gas can be obtained by liquefaction and fractional distillation too. In fact, nitrogen is found in all living systems as part of the makeup of biological compounds.

The Element
The French chemist Antoine Laurent Lavoisier mistakenly named nitrogen azote, meaning without life. However, nitrogen compounds are found in foods, organic materials, fertilizers, poisons, and explosives as well. Nitrogen, as a gas is colorless, odorless, and generally considered an inert element among other elements. As a liquid (boiling point = minus 195.8oC), it is also colorless and odorless, and is similar in appearance to water. One can prepare nitrogen gas by heating a water solution of ammonium nitrite (NH₄NO₃).

Nitrogen Compounds and Nitrogen in Nature
Sodium nitrate (NaNO₃) and potassium nitrate (KNO₃) are two organic compounds of nitrogen. Other inorganic nitrogen compounds are Nitric acid (HNO₃), Ammonia (NH₃), the Oxides (NO, NO₂, N₂O₄, N₂O), Cyanides (CN-), etc.

Ammonia
Ammonia (NH3) is the most important commercial compound of nitrogen that is produced by the Haber Process. Natural gas (Methane, CH₄) is reacted with steam to produce carbon dioxide and hydrogen gas (H₂) in a two step process. Hydrogen gas and nitrogen gas reacted via the Haber process then produce ammonia. Ammonia is also colorless with a pungent odor is easily liquefied (in fact, the liquid is used as a Nitrogen fertilizer). Ammonia is highly used in the production of urea, NH₂CONH₂ that is used as a fertilizer, used in the plastic industry, and used in the livestock industry as a feed supplement.