Plantilya:Infobox astatine

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Astatine
85At
I

At

Uus
poloniumastatineradon
Appearance
unknown, but probably a black solid; possibly metallic in appearance
General properties
Name, simbolo, kaiphan astatine, At, 85
Pronunciation Plantilya:IPAc-en Plantilya:Respell
or Plantilya:IPAc-en Plantilya:Respell
Element category halogen
sometimes classified as a metalloid (disputed)
Group, period, block 176, p
Standard atomic weight (210)
Electron configuration [Xe] 4f14 5d10 6s2 6p5
2, 8, 18, 32, 18, 7
Electron shells of astatine (2, 8, 18, 32, 18, 7)
History
Discovery Dale R. Corson, Kenneth Ross MacKenzie, Emilio Segrè (1940)
Physical properties
Phase magahi
Melting point 575 K, 302 °C, 576 °F
Boiling point 610 K, 337 °C, 639 °F
Heat of vaporization (At2) 54.39 kJ·mol−1
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
Electronegativity 2.2 (Pauling scale)
Ionization energies 1st: 887.7±38.59 kJ·mol−1
Covalent radius 150 pm
Van der Waals radius 202 pm
Miscellanea
Magnetic ordering no data
Thermal conductivity 1.7 W·m−1·K−1
CAS registry number 7440-68-8
Most stable isotopes
Main article: Isotopes of astatine
iso NA half-life DM DE (MeV) DP
209At syn 5.41 h β+ 3.486 209Po
α 5.758 205Bi
210At syn 8.1 h β+ 3.981 210Po
α 5.632 206Bi
211At syn 7.21 h ε 0.786 211Po
α 5.983 207Bi
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