Name :  Astatine
Symbol :  At
Atomic Number :  85
Atomic Weight :  209.9871
Specific Heat :  -
Melting Point :  302°C
Vaporization :  -
Boiling Point :  337°C
Electronegativity :  2.2
Density@293 K :  -
Discovered :  D.R.Corson, K.R.MacKenzie, E.Segré, United States, 1940
Description :  Unstable, radioactive member of the halogen group.
Uses :  Since its isotopes have such short half-lives there are no commercially significant compounds of astatine.