Terbium
Terbium is a chemical element with symbol Tb and atomic number 65. It is a silvery-white rare earth metal that is malleable, ductile and soft enough to be cut with a knife. Terbium is never found in nature as a free element, but it is contained in many minerals, including cerite, gadolinite, monazite, xenotime and euxenite.
A stylized shell model. Electrons are quantum objects, not particles following these literal paths. Sizes and motion are illustrative.
54 is the [Xe] core total across five shells.
At a glance
- Atomic number
- 65
- Atomic mass
- 158.925352 u
- Phase
- Solid
- Density
- 8.23 g/cm³
- Melting point
- 1,629 K
- Boiling point
- 3,396 K
- First ionization energy
- 565.8 kJ/mol
- Electronegativity
- 1.1
- Electron affinity
- 112.4 kJ/mol
- Molar heat capacity
- 28.91 J/(mol·K)
- Period
- 6
- Appearance
- silvery white
Conditions and isotopes affect measured properties. Some properties of short-lived elements are predicted. Electronegativity uses the Pauling scale.
Keep exploring
Explore the stories, imagery, and reference data in more depth. Properties with no value in the reference are marked unavailable.