Erbium

Lanthanide · 167.26 u · group 3, period 6

Erbium · Er

Atomic number68

SymbolEr

CategoryLanthanide

Standard stateSolid

Group · Period · Block3 · 6 · f

Electron configuration[Xe]6s2 4f12

Atomic mass167.26 u

Atomic radius235 pm

Protons / Neutrons / Electrons68 / 99 / 68

Shells (e⁻ per shell)2, 8, 18, 30, 8, 2

Electronegativity (Pauling)1.24

Ionization energy6.108 eV

Electron affinity—

Oxidation states+3

Melting point1.80e+3 K · 1.53e+3 °C

Boiling point3.14e+3 K · 2.87e+3 °C

Density9.07 g/cm³

Year discovered1843

CPK color

#f783ac

State at room temp (25 °C)

solid

Position