85 – At – Astatine

At-218 (half life 1.6 seconds) is part of the decay chain of U-238, so traces of Astatine exist in the pitchblende shown here. Amount: 0.2 g pitchblende, corresponding to 0.002 ag or 6 atoms of At-218.

Physical and chemical data
Atomic mass	209.9871
Density	? g·cm^-3
Melting point	302 °C
Boiling point	337 °C
Abundance	3.00e-24 %
Electronegativy	2
Oxydation levels	7, 5, 3, 1, [-1]
Electron configuration	[Xe]4f14 5d10 6s2 6p5