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| | Astatine Basic information |
| | Astatine Chemical Properties |
| Melting point | 302°C | | Boiling point | 333.81°C (estimate) | | solubility | soluble in HNO3, organic solvents | | form | crystals | | color | crystals, crystalline | | Water Solubility | soluble organic solvents [MER06] |
| | Astatine Usage And Synthesis |
| Chemical Properties | radioactive crystal(s) halogen with 20 isotopes; heaviest of the halogens; 209At, t1/2=5.5 h; 210At, t1/2=8.3 h; more metallic than iodine; preparation: from Bi by α-particle bombardment; possible medical uses, concentrates in thyroid gland [HAW93] [MER06] | | Physical properties | Physical properties of this element have not been well investigated due to short half-lives of isotopes. The element is volatile; may be distilled in vacuum at room temperature in a glass apparatus; and condensed in a dry ice trap. It is soluble in chloroform, ether, hexane and many other organic solvents. Solubility in water should be of low order. | | Occurrence | Astatine is one of the rarest elements in nature. Extremely small amounts of short-lived isotopes At-215, At-217, At-218 and At-219 are naturally found occurring in equilibrium with uranium, neptunium and thorium isotopes. The element was named by Corson, MacKenzie and Segre who produced the first of its isotope At-211 in 1940 by bombarding bismuth with alpha particles. Since then many isotopes in the mass range 200 to 219 have been synthesized. All isotopes, however, are unstable, their half-lives ranging between a few microseconds to less than ten hours. The most stable ones are At-210, At-211 and At-209. No use of this element is known so far. | | Definition | ChEBI: Diastatine is an elemental astatine. | | Hazard | Exposure to radiation may cause cancer. Studies on experimental animals show it induces tumors. |
| | Astatine Preparation Products And Raw materials |
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