Comparison of Lanthanum and Praseodymium

Attribute	Praseodymium ×	Lanthanum ×
Atomic mass (u)	140.90766	138.9055
Standard state	Solid	Solid
Oxidation states	+3	+3
Electron configuration	[Xe]6s²4f³	[Xe]6s²5d¹
Atomic radius (van der waals) (pm)	239	240
Electronegativity (pauling scale)	1.13	1.1
Electron affinity (eV)	-	0.5
Ionization energy (eV)	5.464	5.577
Boiling point (K)	3793	3737
Melting point (K)	1204	1191
Density (g/cm³)	6.77	6.15
Atomic number	59	57
Group name	Lanthanide	Lanthanide
Symbol	Pr	La
Discovered (year)	1885	1839