Template:Infobox astatine

Astatine,  ₈₅At

General properties
Pronunciation	Template:Infobox element/pronunciation
Appearance	unknown, probably metallic
Standard atomic weight (Ar, standard)	Template:Infobox element/standard atomic weight
Mass number	Template:Infobox element/symbol-to-most-stable-isotope (most stable isotope)
Astatine in the periodic table
Template:Infobox element/periodic table
Atomic number (Z)	85
Group	Template:Infobox element/group
Period	period 6
Block	p-block
Element category	Template:Infobox element/category format, sometimes classified as a nonmetal, or a metalTemplate:Sfn
Electron configuration	[Xe] 4f14 5d10 6s2 6p5
Electrons per shell	2, 8, 18, 32, 18, 7
Physical properties
Phase at STP	solid
Melting point	575 K ​(302 °C, ​576 °F)
Boiling point	610 K ​(337 °C, ​639 °F)
Density (near r.t.)	(At2) 6.35±0.15 g/cm3 (predicted)
Molar volume	(At2) 32.94 cm3/mol (predicted)
[[Enthalpy of vaporization|Heat of Template:Engvar]]	(At2) 54.39 kJ/mol
[[Vapor pressure|Template:Engvar pressure]] Template:Infobox element/vapor pressure table
Atomic properties
Oxidation states	Template:Infobox element/symbol-to-oxidation-state
Electronegativity	Pauling scale: 2.2
[[Ionization energy|Template:Engvar energies]]	1st: 899.003 kJ/mol
Covalent radius	150 pm
Van der Waals radius	202 pm
Template:Infobox element/spectral lines
Other properties
Crystal structure	​Template:Infobox element/crystal structure Template:Infobox element/crystal structure (predicted)
Thermal conductivity	1.7 W/(m·K)
CAS Number	7440-68-8
History
Naming	after Greek astatos (αστατος), meaning "unstable"
Discovery	Dale R. Corson, Kenneth Ross MacKenzie, Emilio Segrè (1940)
Main isotopes of astatine
Template:Infobox element/isotopes table