Comparison of Strontium and Europium

Attribute	Europium ×	Strontium ×
Standard state	Solid	Solid
Electron configuration	[Xe]6s²4f⁷	[Kr]5s²
Atomic mass (u)	151.964	87.62
Electronegativity (pauling scale)	-	0.95
Oxidation states	+2 +3	+2
Ionization energy (eV)	5.67	5.695
Atomic radius (van der waals) (pm)	233	249
Boiling point (K)	1802	1655
Melting point (K)	1095	1050
Density (g/cm³)	5.24	2.64
Atomic number	63	38
Group name	Lanthanide	Alkaline earth metal
Symbol	Eu	Sr
Discovered (year)	1901	1790