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Nitrogen
Nitrogen

Nitrogen

Chemical formula: N2, usually a colorless, odorless, odorless and nontoxic gas, and generally nitrogen is less dense than air. Nitrogen accounts for 78.08%(volume fraction) of the total atmosphere and is one of the main components of air. At standard atmospheric pressure, nitrogen becomes a colorless liquid when cooled to-195.8℃, and liquid nitrogen becomes a snow-like solid when cooled to-209.8℃. Nitrogen is chemically inert, almost completely inert, and can cause asphyxiation at high concentrations.