Comparison of Xenon and Astatine

Attribute	Xenon ×	Astatine ×
Standard state	Gas	Solid
Electron affinity (eV)	-	2.8
Electron configuration	[Kr]5s²4d¹⁰5p⁶	[Xe]6s²4f¹⁴5d¹⁰6p⁵
^1↑Atomic mass (u)	131.29	209.98715
Electronegativity (pauling scale)	2.6	2.2
Oxidation states	0	-1 1 3 5 7
Ionization energy (eV)	12.13	9.5
Atomic radius (van der waals) (pm)	216	202
Boiling point (K)	165.03	-
Melting point (K)	161.36	575
Density (g/cm³)	0.005887	7
Atomic number	54	85
Group name	Noble gas	Halogen
Discovered (year)	1898	1940
Symbol	Xe	At