Holmium (Ho) – element 67
Holmium is a chemical element with the symbol Ho and atomic number 67. It is a lanthanide in group 3 (lanthanides), period 6 of the periodic table (f-block), and is a solid at room temperature.
Holmium (Ho) has atomic number 67, atomic mass 164.93 u and electron configuration [Xe] 4f11 6s2.
Holmium facts
| Symbol | Ho |
|---|---|
| Atomic number | 67 |
| Atomic mass | 164.93 u (g/mol) |
| Category | lanthanide |
| Group | group 3 (lanthanides) |
| Period | 6 |
| Block | f-block |
| Phase at 20 °C | Solid |
| Electron configuration | 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f11 |
| Noble-gas notation | [Xe] 4f11 6s2 |
| Electrons per shell | 2, 8, 18, 29, 8, 2 |
Bohr model and shells
Holmium has 67 electrons in 6 shells: 2, 8, 18, 29, 8, 2. Full configuration and noble-gas notation are in the table; work out any element or ion with the electron configuration calculator.
Physical and atomic properties
| Melting point | 1734 K (1460.8 °C) |
|---|---|
| Boiling point | 2873 K (2599.8 °C) |
| Density | 8.79 g/cm³ |
| Electronegativity (Pauling) | 1.23 |
| Electron affinity | 32.61 kJ/mol |
| Ionization energies | 581, 1140, 2204 kJ/mol (1st, 2nd, 3rd) |
| Molar heat capacity | 27.15 J/(mol·K) |
| Discovered by | Marc Delafontaine |
Use the atomic mass in the molar mass calculator for any formula containing Ho.
Position in the periodic table
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Frequently asked questions
What is the atomic mass of holmium?
The atomic mass of holmium is 164.93 u, so one mole of holmium atoms weighs 164.93 g.
What is the electron configuration of holmium?
Holmium has 67 electrons: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f¹¹, or [Xe] 4f¹¹ 6s² in noble-gas notation. Electrons per shell: 2, 8, 18, 29, 8, 2.
Is holmium a metal?
Yes. Holmium is a lanthanide.
Where is holmium on the periodic table?
Holmium is in group 3 (lanthanides), period 6, in the f-block.
Data: Periodic-Table-JSON (CC BY-SA 3.0); standard atomic weights from IUPAC (abridged). Values in brackets are the mass number of the longest-lived isotope.