Comparison of Chlorine and Radon

Attribute	Radon ×	Chlorine ×
Atomic mass (u)	222.01758	35.45
Standard state	Gas	Gas
Oxidation states	0	-1 +1 +5 +7
Electron configuration	[Xe]6s²4f¹⁴5d¹⁰6p⁶	[Ne]3s²3p⁵
Atomic radius (van der waals) (pm)	220	175
Electronegativity (pauling scale)	-	3.16
Electron affinity (eV)	-	3.617
Ionization energy (eV)	10.745	12.968
Boiling point (K)	211.45	239.11
Melting point (K)	202	171.65
Density (g/cm³)	0.00973	0.003214
Atomic number	86	17
Group name	Noble gas	Halogen
Symbol	Rn	Cl
Discovered (year)	1900	1774