NITROGEN

• Atomic Number: 7
• Atomic Symbol: N
• Atomic Weight: 14.00674
• Electron Configuration: 2-5

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History:

(L. nitrum, Gr. nitron, native soda; genes, forming) Discovered by Daniel Rutherford in 1772, but Scheele, Cavendish, Priestley, and others at about the same time studied "burnt or dephlogisticated air," as air without oxygen was then called. Nitrogen makes up 78% of the air, by volume. The atmosphere of Mars, by comparison, is 2.6% nitrogen. The estimated amount of this element in our atmosphere is more than 4000 trillion (?). From this inexhaustible source it can be obtained by liquifaction and fractional distillation. Nitrogen molecules give the orange-red, blue-green, blue-violet, and deep violet shades to the aurora. The element is so inert that Lavoisier named it azote, meaning without life, yet its compounds are so active as to be most important in foods, poisons, fertilizers, and explosives. Nitrogen can also be easily prepared by heating a water solution of ammonium nitrite. Nitrogen, as a gas, is colorless, odorless, and a generally inert element. As a liquid it is also colorless and odorless, and is similar in appearance to water. Two allotropic forms of solid nitrogen exist, with the transition from the alpha to the beta form taking place at -237C. When nitrogen is heated, it combines directly with magnesium, lithium, or calcium; when mixed with oxygen and subjected to electric sparks, it forms first nitric acid (NO) and then the dioxide (NO2); when heated under pressure with a catalyst with hydroge The ammonia that is formed is of the utmost importance as it is used in fertilizers, and can be oxidized to nitric acid (Ostwald process). The ammonia industry is the largest consumer of nitrogen. Large amounts of gas are also used by the electronics industry, which uses the gas as a blanketing medium during production of such componenets as transistors, diodes, etc. Large quantities of nitrogen are used in annealing stainless steel and other steel mill products. The drug industry also uses large quantities. Nitrogen is used as a refrigerant both for the immersion freezing of food products and for transportation of foods. Liquid nitrogen is also used in missile work as a purge for components, insulators for space chambers, etc., and by the oil industry to build up great pressures in wells to force crude oil upward. Sodium and potassium nitrates are formed by the decomposition of organic matter with compounds of the metals present. In certain dry areas of the world these saltpeters are found in quantity. Ammonia, nitric acid, the nitrates, the five oxides, TNT, the cyanides, etc. are but a few of the important compounds. Nitrogen gas prices vary from 2 cents to $2.75 per 100 ft^3 depending on purity, etc. Production of elemental nitrogen in the U.S. is more than 9 million short tons per year.

Source: CRC Handbook of Chemistry and Physics, 1913-1995. David R. Lide, Editor in Chief. Author: C.R. Hammond