Chemistry Reference
In-Depth Information
NITROGEN (N
)
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Properties
Nitrogen is a colorless, odorless gas making up about
78% of the air. It can be liquified under pressure. At
normal temperatures, it is unreactive (inert).
Commercial grades
Various purities (with respect to oxygen content) as
gas or liquid.
Uses
Manufacture of ammonia, inert atmosphere for
chemical reactions, metal treating, enhanced oil
recovery, food processing (freezing), electronics.
Manufacture
Filtered air is compressed and cooled to remove water
and carbon dioxide. The oxygen/nitrogen mixture is
further cooled in a distillation column and the lower
boiling nitrogen distilled from the higher boiling
oxygen.
Suppliers
Air Liquide America Corp., Air Products, BOC Gases,
Praxair.
Many of nitrogen's uses depend on the fact that it is chemically inert, that
is, it does not readily react with other chemicals. The exception to this, and a
very important exception, is its reaction with hydrogen at high temperature
over a catalyst to make ammonia (NH
and
is one of the most important processes in the chemical industry because it
provides the nitrogen contained in almost all synthetic chemicals containing
chemically combined nitrogen and all nonorganic fertilizer. Thus, the nitro-
gen compounds, such as ammonia, that farmers use to stimulate crop growth
come indirectly from the air.
). This is called
nitrogen fixation
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