Sciencemadness Discussion Board
Not logged in [Login ]
Go To Bottom

Printable Version  
Author: Subject: Astatine
Pyrovus
Hazard to Others
***




Posts: 241
Registered: 13-10-2003
Location: Australia, now with 25% faster carrier pigeons
Member Is Offline

Mood: heretical

[*] posted on 5-11-2003 at 22:35
Astatine


I've been looking for information on this element for a while, because for some reason Astatine holds a particular fascination to me. However, all the information I've been able to find on it's chemical properties is the bleeding obvious -"it's a bit like iodine". While it is highly radioactive, I do know for a fact that they have done some investigation into it's properties, but they never go into detail. I'm just wondering if anybody here knows anything about Astatine.
View user's profile View All Posts By User
Mephisto
Chemicus Diabolicus
***




Posts: 295
Registered: 24-8-2002
Location: Germany
Member Is Offline

Mood: swinging

[*] posted on 6-11-2003 at 09:26
Just a short info from Merck Index


Title: Astatine.
CAS Registry number: [7440-68-8]
Literature references: At; at. no. 85. Radioactive halogen; one of the rarest elements in nature. Radioisotopes range in mass number from 200 to 219; naturally occurring isotopes found in uranium ores: 215, 217, 218, 219 (longest-lived natural isotope, T½ 0.9 min); most stable artificial isotopes: 209 (T½ 5.5 hrs); 210 (T½ 8.3 hrs); 211 (T½ 7.21 hrs). First convincingly identified by
Corson et al., Phys. Rev. 58, 672 (1940). 209At, 210At, 211At are obtained artificially by alpha bombardment of bismuth: Kelley, Segre, Phys. Rev. 75, 999 (1949); Johnson et al., J. Chem. Phys. 17, 1, (1949); Neumann, J. Inorg. & Nucl. Chem. 4, 349 (1957). Reviews: Hyde, J. Chem. Ed. 36, 15 (1959); Haissinsky, Adloff, Radiochemical Survey of the Elements (Elsevier, 1965) pp 11-12; Appelman, "Astatine" in MTP Int. Rev. Sci.: Inorg. Chem., Ser. One, vol. 3, V. Gutmann, Ed. (Butterworths, London, 1972) 181-198; Downs, Adams, "Chlorine, Bromine, Iodine and Astatine" in Comprehensive Inorganic Chemistry vol. 2, J. C. Bailar, Jr. et al., Eds. (Pergamon Press, Oxford, 1973) pp 1107-1594.
Properties: More metallic than iodine. Soluble in organic solvents. Due to short half-life of isotopes, only a few physical properties can be measured. Chemical studies are carried out on trace amounts (<10–8M solns). HAt, CH3At, AtCl, AtBr, AtI have been identified by time-of-flight mass spectrometry: Appleman et al., Inorg. Chem. 5, 766 (1966). Oxidation states: –1, 0, +5; existente of +1, +3, +7 oxidation states uncertain; E0(aq) At/At– 0.3 V: Appleman, J. Am. Chem. Soc. 83, 805 (1961). When fed to Guinea pigs, is found in the thyroid gland. Mammary and pituitary tumors can be induced with a single injection.
View user's profile Visit user's homepage View All Posts By User

  Go To Top