Comparison of Sodium and Potassium

Attribute	Sodium ×	Potassium ×
Atomic mass (u)	22.9897693	39.0983
Standard state	Solid	Solid
Oxidation states	+1	+1
Electron configuration	[Ne]3s¹	[Ar]4s¹
Atomic radius (van der waals) (pm)	227	275
Electronegativity (pauling scale)	0.93	0.82
Electron affinity (eV)	0.548	0.501
Ionization energy (eV)	5.139	4.341
Boiling point (K)	1156	1032
Melting point (K)	370.95	336.53
Density (g/cm³)	0.97	0.89
Atomic number	11	19
Group name	Alkali metal	Alkali metal
Discovered (year)	1807	1807
Symbol	Na	K