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Astatine, 00At
Astatine
Pronunciation /ˈæstətn, -tɪn/ ( ASS-tə-teen, -⁠tin)
Appearanceunknown, probably metallic
Mass number[210]
Astatine in the periodic table
Hydrogen Helium
Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon
Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon
Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton
Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon
Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon
Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson
I

At

Uus
poloniumastatineradon
Group group 17 (halogens)
Period period 6
Block  p-block
Electron configuration[ Xe] 4f14 5d10 6s2 6p5
Electrons per shell2, 8, 18, 32, 18, 7
Physical properties
Phase at  STPsolid
Melting point575  K ​(302 °C, ​576 °F)
Boiling point610 K ​(337 °C, ​639 °F)
Density (near  r.t.)(At2) 6.2–6.5 g/cm3 (predicted) [1]
Heat of fusionca. 6  kJ/mol
Heat of vaporization(At2) 54.39 kJ/mol
Vapor pressure
P (Pa) 1 10 100 1 k 10 k 100 k
at  T (K) 361 392 429 475 531 607
Atomic properties
Oxidation states−1, +1, +3, +5, +7 [2]
ElectronegativityPauling scale: 2.2
Ionization energies
  • 1st: 899.003 kJ/mol [3]
Covalent radius150  pm
Van der Waals radius202 pm
Other properties
Natural occurrence from decay
Crystal structureface-centered cubic (fcc)
Face-centered cubic crystal structure for astatine

(predicted) [4]
Thermal conductivity1.7 W/(m⋅K)
CAS Number7440-68-8
History
Namingafter Greek: αστατος (astatos), meaning "unstable"
Discovery Dale R. Corson, Kenneth Ross MacKenzie, Emilio Segrè (1940)
Isotopes of astatine
Main isotopes [5] Decay
abun­dance half-life (t1/2) mode pro­duct
209At synth 5.41 h β+ 209Po
α 205Bi
210At synth 8.1 h β+ 210Po
α 206Bi
211At synth 7.21 h ε 211Po
α 207Bi
  Category: Astatine
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References

  1. ^ Bonchev, D.; Kamenska, V. (1981). "Predicting the properties of the 113–120 transactinide elements". The Journal of Physical Chemistry. 85 (9). ACS Publications: 1177–86. doi: 10.1021/j150609a021. Retrieved 6 May 2013.
  2. ^ Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. p. 28. ISBN  978-0-08-037941-8.
  3. ^ Rothe, S.; Andreyev, A. N.; Antalic, S.; Borschevsky, A.; Capponi, L.; Cocolios, T. E.; De Witte, H.; Eliav, E.; Fedorov, D. V.; Fedosseev, V. N.; Fink, D. A.; Fritzsche, S.; Ghys, L.; Huyse, M.; Imai, N.; Kaldor, U.; Kudryavtsev, Yuri; Köster, U.; Lane, J. F. W.; Lassen, J.; Liberati, V.; Lynch, K. M.; Marsh, B. A.; Nishio, K.; Pauwels, D.; Pershina, V.; Popescu, L.; Procter, T. J.; Radulov, D.; Raeder, S. (2013). "Measurement of the first ionization potential of astatine by laser ionization spectroscopy". Nature Communications. 4: 1–6. doi: 10.1038/ncomms2819. PMC  3674244. PMID  23673620. {{ cite journal}}: Unknown parameter |displayauthors= ignored (|display-authors= suggested) ( help)
  4. ^ a b Hermann, A.; Hoffmann, R.; Ashcroft, N. W. (2013). "Condensed Astatine: Monatomic and Metallic". Physical Review Letters. 111 (11): 116404-1–116404-5. doi: 10.1103/PhysRevLett.111.116404.
  5. ^ Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S.; Audi, G. (2021). "The NUBASE2020 evaluation of nuclear properties" (PDF). Chinese Physics C. 45 (3): 030001. doi: 10.1088/1674-1137/abddae.