Chemical formula of liquid nitrogen

The chemical formula of liquid nitrogen is n? .

Liquid nitrogen refers to inert, colorless, tasteless, non-corrosive, nonflammable nitrogen obtained at extremely low temperature. Liquid nitrogen is an inert, colorless, tasteless, low viscosity, non-corrosive, non-flammable transparent liquid with extremely low temperature. When vaporizing, a lot of endothermic contact will lead to frostbite.

Nitrogen constitutes most of the atmosphere (78.03% by volume and 75.5% by weight). At atmospheric pressure, the boiling point of nitrogen is-196.56℃, and 1 m3 of liquid nitrogen can expand to 696 m3 of pure gaseous nitrogen (2 1℃).

If pressurized, liquid nitrogen can be obtained at a higher temperature. If the human body is exposed to liquid nitrogen without protective measures, the skin may be severely frostbitten. If there is too much nitrogen produced by evaporation under normal pressure, the partial pressure of oxygen in the air may decrease, causing hypoxia and suffocation.

Precautions for operation: close the operation and provide good natural ventilation conditions. Operators must be specially trained and strictly abide by the operating procedures. The temperature of liquid nitrogen at normal pressure is very low, and once it touches the surface of an object, it will boil quickly, and at the same time, it will take away a lot of heat energy quickly. Therefore, special attention should be paid when using liquid nitrogen to avoid direct contact with skin.

danger

Liquid nitrogen will quickly volatilize into nitrogen at room temperature and change from liquid to gas. At the same time, the volume will expand rapidly, and storage in a non-pressure closed container may lead to gas explosion. If it is a non-positive pressure storage barrel, do not store liquid nitrogen in a sealed container at room temperature.

Nitrogen is an inert substance. If liquid nitrogen is used in a closed space, the evaporated nitrogen will fill the whole space and slowly replace the oxygen in the air, which will reduce the oxygen concentration and suffocate people, so it is necessary to use liquid nitrogen in an open space.