Periodic Table of Elements




Terbium was discovered in 1843 by the Swedish chemist Carl Gustaf Mosander.

Name: Terbium
Symbol: Tb
Atomic number: 65
Atomic weight: 158.93
State: solid
Group, period, block: n/a, 6, f
Color: silvery white
Classification: lanthanide
Electron configuration: 4f9 6s2

Physical properties

Density: 8.23 g/cm-3
Melting point: 1629 K,1356 C,2473 F
Boiling point: 3503 K,3230 C,5846 F

Atomic properties

Oxidation states: 4, 3, 2, 1
Electronegativity: 1.2 (Pauling scale)
Ionization energies: 1st: 565.8 kJmol-1
Covalent radius: 1945 pm
Van der Waals radius: no data
  • Tb
  • Electron Configuration


There is one naturally occurring isotope of terbium exists, 159Tb.