Comparison of Californium and Mendelevium

Attribute	Mendelevium ×	Californium ×
Standard state	Solid	Solid
Electron configuration	[Rn]7s²5f¹³	[Rn]7s²5f¹⁰
Atomic mass (u)	258.09843	251.07959
Electronegativity (pauling scale)	1.3	1.3
Oxidation states	+2 +3	+3
Ionization energy (eV)	6.58	6.3
Atomic radius (van der waals) (pm)	-	245
Melting point (K)	1100	1173
Atomic number	101	98
Group name	Actinide	Actinide
Symbol	Md	Cf
Discovered (year)	1955	1950