Lutetium

Lanthanide · 174.9668 u · group 3, period 6

Lutetium · Lu

Atomic number71

SymbolLu

CategoryLanthanide

Standard stateSolid

Group · Period · Block3 · 6 · f

Electron configuration[Xe]6s2 4f14 5d1

Atomic mass174.9668 u

Atomic radius221 pm

Protons / Neutrons / Electrons71 / 104 / 71

Shells (e⁻ per shell)2, 8, 18, 32, 9, 2

Electronegativity (Pauling)1.27

Ionization energy5.426 eV

Electron affinity—

Oxidation states+3

Melting point1.94e+3 K · 1.66e+3 °C

Boiling point3.68e+3 K · 3.40e+3 °C

Density9.84 g/cm³

Year discovered1907

CPK color

#00AB24

State at room temp (25 °C)

solid

Position