Terbium

Lanthanide · atomic number 65

65158.925352TbTerbiumSolidLanthanide

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.

Properties of Terbium

Element category	Lanthanide
Atomic number	65
Atomic mass	158.925352 u
Phase at STP	Solid
Group	3
Period	6
Block	f
Electron configuration	[Xe] 4f9 6s2
Electrons per shell	2, 8, 18, 27, 8, 2
Electronegativity (Pauling)	1.1
Melting point	1629 K (1356 °C)
Boiling point	3396 K (3123 °C)
Density	8.23 g/cm3
Discovered by	Carl Gustaf Mosander

← Gadolinium · Periodic table · Dysprosium → Dy

About the lanthanide group

The rare-earth “inner transition” metals that give strong permanent magnets, screen phosphors and catalyst polish.

Data: Periodic-Table-JSON (CC BY-SA 3.0) · stored statically on our server. https://en.wikipedia.org/wiki/Terbium

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