N
NITROGEN
(L. nitrum, Gr. nitron, native soda; genes, forming)
N at. wt. 14.0067
at. no. 7
m.p. -209.86°C
b.p. - 195.8°C
density 1.2506 gm/l
sp. gr. liquid 0.808 (- 195.8°C)
sp. gr. solid 1.026 (-252°C)
valence 3, or 5.
Electronic configuration
| SHELL |
K |
L |
M |
N |
O |
P |
Q |
| SUB SHELL |
He |
Neon |
Argon |
Krypton |
Xenon |
Radon |
Eka-radon |
| 1s |
2s 2p |
3s 3p |
3d 4s 4p |
4d 5s 5p |
4f 5d 6s 6p |
5f 6d 7s 7p |
| Nitrogen
|
1s22s22p3 |
|
|
|
|
|
| Symbol
|
4S3/2 |
Nitrogen was discovered by Daniel Rutherford in 1772, but Scheele, Cavendish,
Priestley, and others 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 estimated
amount of this element in the atmosphere is more than 4000
billion tons. From this inexhaustible source it can be obtained
by liquefaction and fractional distillation. Nitrogen mole-
cules give the orange-red, blue-green, blue-violet, and deep
violet shades to the aurora. The element is so inert that
I,,avoisier named it azote, meaning without life, yet its com-
pounds are so active as to be most important in foods,
poisons, fertilizers, and explosives. Nitrogen can be also
easily prepared by heating a water solution of ammonium
nitrite. Nitrogen, as a gas, is colorless, odorless, and a
generally inert element.As a liqiuid it is also colorless and
odorless, and is similar in appearance to water. Two 8110'
tropic forms of solid nitrogen exist, with the transition from
the a to the p form taking place at - 2370C. 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 oxide (NO) and then the dioxide
(N02); when heated under pressure with a catalyst with
hydrogen, ammonia is formed (Haber process). The an~-
monia thus formed is of the utmost importance as i{)5 used
in fertilizers, and it can be oxidized to nitric acid (Ostwald
process). The ammonia industry is the largest consumer of
rntrogen Large amounts of the gas are also used by the
electronics industry, which uses the gas as a blanketing
medium during production of such components as transis-
tors, diodes, etc. 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 (N20, NO, N203, N02, and N205),
TNT, the cyanides, etc., are but a few of the important com-
pounds. Nitrogen gas prices vary from 2t to $2.75 per 100
cu. ft., depending on purity, etc. Production of nitrogen in
the U,S. is more than 40 billion cubic fret per year.
© 1999 F. Davies
Delphi O.E.M. Co.
All rights reserved
