Comparison of Fermium and Lawrencium

Attribute	Lawrencium ×	Fermium ×
Atomic mass (u)	266.12	257.09511
Standard state	Solid	Solid
Oxidation states	+3	+3
Electron configuration	[Rn]7s²5f¹⁴6d¹	[Rn]5f¹²7s²
Ionization energy (eV)	-	6.5
Electronegativity (pauling scale)	1.3	1.3
Melting point (K)	1900	1800
Atomic number	103	100
Group name	Actinide	Actinide
Symbol	Lr	Fm
Discovered (year)	1961	1952