General | States | Energies | Oxidation & Electrons |Appearance & Characteristics
Reactions | Other Forms |Radius | Conductivity | Abundance
Encyclopedia Britannica articles


Name Astatine Symbol At
atomic number 85 Atomic weight (210)
Density @ 293 K ? Atomic volume ?
Group Halogen discovered 1940


state (s, l, g) s
melting point 575.2 K boiling point K
Heat of fusion ? Heat of vaporization ?
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1st ionization energy 890 kJ/mole electronegativity 2.2
2nd ionization energy kJ/mole electron affinity 270 kJ/mole
3rd ionization energy kJ/mole Specific heat ?
heat atomization 92 kJ/mole atoms

Oxidation & Electrons

Shells 2,8,18,32,18,7 electron configuration [Xe] 4f14 5d10 6s2 6p5
minimum oxidation number -1 maximum oxidation number 7
min. common oxidation no. -1 max. common oxidation no. 1
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Appearance & Characteristics

structure color
uses toxicity
hardness mohs characteristics Radioactive


reaction with air reaction with 6M HCl
reaction with 6M HCl reaction with 15M HNO3
reaction with 6M NaOH
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Other Forms

number of isotopes 0 hydride(s) HAt
oxide(s) chloride(s)


ionic radius (2- ion) pm ionic radius (1- ion) pm
atomic radius pm ionic radius (1+ ion) pm
ionic radius (2+ ion) pm ionic radius (3+ ion) pm
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thermal conductivity J/m-sec-deg electrical conductivity 1/mohm-cm
polarizability 6 A^3


source Synthetic(Th or U decay) rel. abund. solar system log
abundance earth's crust log cost, pure $/100g
cost, bulk $/100g
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World Wide Web presentation of Chemicool Periodic Table is © Copyright 1996-99 by David D. Hsu. Some data were provided by and used with the permission of JCE Software and is owned and copyright by the Division of Chemical Education, Inc. Additional data were provided by Perkin-Elmer through Peter Lykos of IIT. The information may not be redistributed without the permission of David Hsu or JCE Software.