Holmium
Definition and meaning of Holmium in chemistry.
![Holmium element card: symbol Ho, atomic number 67, atomic mass 164.93, electron configuration [Xe] 4f¹¹ 6s², oxidation states +3, Lanthanide, f-block, period 6, solid at room temperature.](/assets/images/terms/holmium-chemical-element.webp)
Holmium is a chemical element with the symbol Ho and the atomic number 67. It is a relatively soft and malleable silvery-white metal belonging to the lanthanide series. It stays stable in dry room-temperature air, but it rapidly rusts in moist air or extreme heat.
In more detail
Holmium occurs naturally inside specific rare-earth minerals like gadolinite and monazite. Mining companies commercially isolate the pure metal by using advanced chemical ion-exchange techniques. Sitting in the f-block, it possesses the highest magnetic moment of any naturally occurring element.
A high magnetic moment means its individual atoms act like very strong microscopic magnets. This trait gives holmium some very unique and powerful magnetic properties. When placed inside a magnetic field, the metal heavily concentrates the magnetic flux.
This concentrating effect makes it highly valuable for creating strong artificial magnetic poles. Chemically, it behaves very much like the other heavy rare-earth lanthanide metals. It forms chemical compounds almost exclusively in the +3 oxidation state.
The metal burns in regular air to form a solid compound called holmium oxide, Ho2O3. This solid oxide exhibits striking and unusual color changes depending on the surrounding lighting conditions. It appears pale yellow in natural daylight and turns fiery orange under fluorescent light.
Holmium also has an unusually high ability to absorb free-flying subatomic neutrons. This special neutron-absorbing trait drives its heavy use inside specialized nuclear reactor control rods.
Key facts
| Field | General Chemistry |
|---|---|
| Symbol | Ho |
| Atomic number | 67 |
| Atomic mass | 164.93 u |
| Category | Lanthanide |
| State at room temperature | Solid |
| Magnetic moment | 10.6 µB (highest of any element) |
Engineers frequently use holmium to build solid-state lasers for medical and dental surgical procedures. These specialized lasers operate at precise and completely eye-safe light wavelengths. Doctors use them to carefully cut human tissue without causing extensive heat damage to surrounding areas.
Frequently asked questions
What makes holmium unique among elements?
It possesses the highest magnetic strength of any naturally occurring element. This powerful magnetic moment makes it perfect for specialized magnetic applications.
How is holmium used in medicine?
Holmium lasers emit light at a wavelength that water highly absorbs. This makes them excellent for precise tissue cutting in urological and dental surgeries.
Related terms
Sources & references
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