At アスタチン 85 (210) 17 6 p 85 302.0 337.0 [Xe] 4f14 5d10 6s2 6p5 2 8 18 32 18 7 None Silver Unknown 2.2 2.39 {"1":"890"} 920 270.1 142 1.45 12.0 30.0 1.7 1 8.06 h 11.7h BetaPlusDecay Solid, Halogen, Radioactive, Synthetic, Nonmetal AS-teh-teen Unstable, radioactive member of the halogen group. Since its isotopes have such short half-lives there are no commercially significant compounds of astatine. Does not occur in nature. Similar to iodine. Produced by bombarding bismuth with alpha particles. sSL7EwdlLlE Astatine

Nitrogen is considered to have been discovered by Scottish physician Daniel Rutherford in 1772, who called it noxious air or fixed air.

It was also studied at about the same time by Carl Wilhelm Scheele, Henry Cavendish and Joseph Priestley.

In 1790 the French chemist Jean-Antoine-Claude Chaptal named the element nitrogen. From the Latin word nitrum, Greek Nitron, native soda; and genes, forming 85 1940 Dale Corson, MacKenzie, Segre California, USA From the Greek word "astatos" meaning "unstable"

Rapid release of nitrogen gas into an enclosed space can displace oxygen, and therefore represents an asphyxiation hazard

Nitrogen is present in all living organisms, in proteins, nucleic acids and other molecules

Nitrogen is used to produce ammonia and fertilizers, vital for current food production methods.

Liquid nitrogen is used as a refrigerant.

Nitric acid is used as an oxidizing agent in liquid fueled rockets.

Nitrogen is a constituent of molecules in every major drug class in pharmacology and medicine.