Holmium

Lanthanide · atomic number 67

67164.930332HoHolmiumSolidLanthanide

Holmium is a chemical element with symbol Ho and atomic number 67. Part of the lanthanide series, holmium is a rare earth element. Holmium was discovered by Swedish chemist Per Theodor Cleve.

Properties of Holmium

Element category	Lanthanide
Atomic number	67
Atomic mass	164.930332 u
Phase at STP	Solid
Group	3
Period	6
Block	f
Electron configuration	[Xe] 4f11 6s2
Electrons per shell	2, 8, 18, 29, 8, 2
Electronegativity (Pauling)	1.23
Melting point	1734 K (1461 °C)
Boiling point	2873 K (2600 °C)
Density	8.79 g/cm3
Discovered by	Marc Delafontaine

← Dysprosium · Periodic table · Erbium → Er

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/Holmium

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