n. Symbol N
A nonmetallic element that constitutes nearly four-fifths of the air by volume, occurring as a colorless, odorless, almost inert diatomic gas, N2, in various minerals and in all proteins and used in a wide variety of applications, including manufacture of ammonia, nitric acid, TNT, and fertilizers, and as a cryogen. Atomic number 7; atomic weight 14.0067; melting point -210.00°C; boiling point -195.80°C; valence 2, 3, 4, 5. See Periodic Table.
[French nitrogène : nitro-, nitric acid (from New Latin; see NITRO-) + -gène, -gen.]
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