Holmium (symbol Ho, atomic number 67) is a rare-earth metal with the highest magnetic strength of any element. It is classified as a lanthanide and sits in the lanthanide series (f-block), period 6 of the periodic table.
Overview
Holmium is the chemical element with atomic number 67 and the symbol Ho. With a standard atomic weight of 164.93, it is a lanthanide. In the periodic table it occupies the lanthanide series (f-block) and period 6, and under standard conditions it is normally a solid. Holmium is a rare-earth metal with the highest magnetic strength of any element.
Atomic structure
An atom of Holmium has 67 protons in its nucleus and, when neutral, 67 electrons arranged in the configuration [Xe] 4f11 6s2. Its standard atomic weight of 164.93 reflects the natural mix of its stable isotopes.
Discovery and place in the table
Holmium was discovered in 1878 by Marc Delafontaine, Jacques-Louis Soret. It follows Dysprosium (Dy) and precedes Erbium (Er) in order of atomic number.
| Atomic number | 67 |
|---|---|
| Symbol | Ho |
| Atomic mass | 164.93 |
| Category | Lanthanide |
| Group | — |
| Period | 6 |
| Electron configuration | [Xe] 4f11 6s2 |
| Phase at STP | Solid |
| Discovered | 1878 (Marc Delafontaine, Jacques-Louis Soret) |