Element 67
Holmium
Lanthanides
Holmium (Ho) is in the f-block of the periodic table — group 3, period 6.
Holmium is a chemical element with symbol Ho and atomic number 67.
Key data
- Atomic number
- 67
- Atomic mass
- 164.930 u
- Group / Period
- 3 / 6
- Block
- f-block
- Phase at STP
- Solid
- Density
- 8.79 g/cm³
- Melting point
- 1460.8 °C
- Boiling point
- 2599.8 °C
- Electron configuration
- [Xe] 4f11 6s2
Periodic table block
Holmium is in the f-block (group 3, period 6). Elements land in the f-block when their highest-energy electrons fill an f subshell — these are the lanthanides and actinides shown beneath the main table.
New to this? Periodic table blocks explained: s, p, d, and f
Common uses
- •Strongest magnets known
- •Surgical lasers
- •Nuclear control rods
Discovery
Year: 1878
Discovered by: Marc Delafontaine
Frequently asked questions
What is the atomic number of Holmium?
Holmium has atomic number 67. Its symbol is Ho and its atomic mass is 164.93 u.
What category of element is Holmium?
Holmium is classified as lanthanides. It sits in group 3, period 6 of the periodic table.
What block of the periodic table is Holmium in?
Holmium is in the f-block (group 3, period 6). Its highest-energy electrons occupy the f subshell — you can see this in its electron configuration, [Xe] 4f11 6s2.
What is Holmium used for?
Common uses of Holmium include: Strongest magnets known, Surgical lasers, Nuclear control rods.
When was Holmium discovered?
Holmium was discovered in 1878 by Marc Delafontaine.
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