Astatine
METALLOID
Phase: Solid
Discovered: Dale R. Corson
Block: P
Summary
Astatine is a very rare radioactive chemical element with the chemical symbol At and atomic number 85. It occurs on Earth as the decay product of various heavier elements. All its isotopes are short-lived; the most stable is astatine-210, with a half-life of 8.1 hours.
Appearance: unknown, probably metallic
Source: WikipediaPhysical Properties
Atomic Mass 210 u
Density 6.35 g/cm³
Melting Point 575 K
Boiling Point 610 K
Molar Heat N/A
Electron Affinity 233 kJ/mol
Ionization Energies
1st: 899.003 kJ/mol