Comparison of Krypton and Xenon

Attribute	Krypton ×	Xenon ×
^1↑Standard state	Gas	Gas
Electron configuration	[Ar]4s²3d¹⁰4p⁶	[Kr]5s²4d¹⁰5p⁶
Atomic mass (u)	83.8	131.29
Electronegativity (pauling scale)	3	2.6
Oxidation states	0	0
Ionization energy (eV)	14	12.13
Atomic radius (van der waals) (pm)	202	216
Boiling point (K)	119.93	165.03
Melting point (K)	115.79	161.36
Density (g/cm³)	0.003733	0.005887
Atomic number	36	54
Group name	Noble gas	Noble gas
Discovered (year)	1898	1898
Symbol	Kr	Xe