Comparison of Oxygen and Krypton

Attribute	Krypton ×	Oxygen ×
Atomic mass (u)	83.8	15.999
Standard state	Gas	Gas
Oxidation states	0	-2
Electron configuration	[Ar]4s²3d¹⁰4p⁶	[He]2s²2p⁴
Atomic radius (van der waals) (pm)	202	152
Electronegativity (pauling scale)	3	3.44
Electron affinity (eV)	-	1.461
Ionization energy (eV)	14	13.618
Boiling point (K)	119.93	90.2
Melting point (K)	115.79	54.36
Density (g/cm³)	0.003733	0.001429
Atomic number	36	8
Group name	Noble gas	Nonmetal
Symbol	Kr	O
Discovered (year)	1898	1774