Name nitrogen
Symbol N
Atomic Weight 14.0067
Atomic Number 7
CAS ID 7727-37-9
Group Number 15
Group Name Pnictogen
Period Number 2
Origin of Name Greek, nitron genes = "nitre forming."
Year Discovered 1792
Discovery Credits D. Rutherford at Edinburgh, Scotland.
Class Non-Metallic
Color Colorless
Standard State Gas at 77 F & 298 K
Description Odorless, colorless gas comprising 78% of the atmosphere. Generally unreactive at room temperature. Extensive inorganic and organic chemistry. Used in fertilizers, acids, explosives, plastics, dyes, etc. Recovered on an industrial scale by the liquefaction of air.

Diagnostic tests: 
As nitrates (NO4-), these detonate and pop when heated on charcoal.
As ammonium (NH4+), a solution of NaOH evolves ammonia gas when heated which is detected by its sharp odor.

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