Ho
Holmium
Element 67 · Lanthanide
Holmium (Ho)
Holmium is a soft, silvery rare-earth metal with the highest magnetic strength of any element.
- Lanthanide
- Period 6
- f-block series
- f-block
- solid at room temperature
Key properties
- Atomic mass
- 164.9303
- u
- Electron configuration
- [Xe] 4f11 6s2
- Melting point
- 1,473.9 °C
- 1,747 K
- Boiling point
- 2,699.9 °C
- 2,973 K
- Density
- 8.8 g/cm³
- Electronegativity
- 1.23
- Pauling
- Atomic radius
- 216 pm
- van der Waals
- 1st ionisation energy
- 6.022 eV
Compare with every element:Electronegativity chartAtomic radius chartIonisation energy chartDensity chart of the elementsMelting point chartElectron configuration chart
Did you know?
Notable facts about holmium
- 01
Holmium pole pieces concentrate the field in the world’s strongest magnets.
- 02
Holmium lasers are used to break up kidney stones.
- 03
Holmium oxide is used to calibrate spectrophotometers.
Applications
What is holmium used for?
- Magnet pole pieces
- Medical lasers
- Nuclear control rods
- Calibration standards
History
Discovery & name origin
Discovered by
Year
Where
Switzerland and Sweden
Name origin
Latin Holmia, “Stockholm”.
Atomic structure
Atomic properties
Atomic structure
Atomic properties
- Atomic number
- 67
- Atomic mass
- 164.9303 u
- Group
- Lanthanides (3)
- Period
- 6
- Block
- f-block
- Electron configuration
- [Xe] 4f11 6s2
- Full configuration
- 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f11
- Electrons per shell
- 2, 8, 18, 29, 8, 2
- Electronegativity (Pauling)
- 1.23
- Electron affinity
- —
- Atomic radius (van der Waals)
- 216 pm
- Stable isotopes
- 1
Oxidation states
Highlighted: common oxidation states (+3).
Successive ionisation energies
Energy to remove each electron in turn (kJ/mol). Big jumps show where a new, inner shell begins.
- 1st581
- 2nd1,140
- 3rd2,204
- 4th4,100
Physical
Physical properties & colour
Physical
Physical properties & colour
- State at 20 °C
- Solid
- Melting point
- 1,747 K · 1,473.9 °C · 2,684.9 °F
- Boiling point
- 2,973 K · 2,699.9 °C · 4,891.7 °F
- Density
- 8.8 g/cm³
- Molar heat capacity
- 27.15 J/(mol·K)
- Appearance
- Silvery white
- CPK model colour
- Copied
The CPK colour is the convention used for this element’s atoms in molecular models.
FAQ
Holmium questions
What is Ho on the periodic table?
Ho is the symbol for holmium, element 67 on the periodic table. It sits in period 6, in the f-block, in the lanthanide category, and has an atomic mass of 164.9303.
What is the atomic number of holmium?
Holmium has atomic number 67, so every holmium atom has 67 protons in its nucleus. Its symbol is Ho and its atomic mass is 164.9303.
Who discovered holmium?
Holmium was discovered by Marc Delafontaine, Jacques-Louis Soret and Per Teodor Cleve in 1878 (Switzerland and Sweden). The name comes from Latin Holmia, “Stockholm”.
What is holmium used for?
Holmium is used for: magnet pole pieces; medical lasers; nuclear control rods; calibration standards.
Is holmium a metal?
Yes. Holmium is a lanthanide, one of the metallic elements.
What is the electron configuration of holmium?
The electron configuration of holmium is [Xe] 4f11 6s2. Its 67 electrons are arranged in shells as 2, 8, 18, 29, 8, 2.