Hafnium
Hafnium (铪, symbol Hf) is chemical element number 72, a Transition Metal in period 6, group 4 of the periodic table, with a standard atomic weight of about 178.49. Silvery, ductile, corrosion-resistant transition metal. Used in nuclear control rods.
Properties
| Atomic number | 72 |
|---|---|
| Symbol | Hf |
| Atomic mass | 178.49 u |
| Category | Transition Metal |
| Period | 6 |
| Group | 4 |
| Electron configuration | [Xe] 4f¹⁴ 5d² 6s² |
| Electronegativity | 1.3 |
| Covalent radius | 175 pm |
| Density | 13.31 g/cm³ |
| Melting point | 2506 K |
| Boiling point | 4876 K |
| Discovery | Coster & von Hevesy, 1923 |
Overview
Silvery, ductile, corrosion-resistant transition metal. Used in nuclear control rods. Hafnium (symbol Hf) is chemical element number 72, sitting in period 6, group 4 of the periodic table and classed as a Transition Metal. As a transition metal it commonly shows several oxidation states, forms coloured compounds, and is widely used in catalysts and alloys.
It has the configuration [Xe] 4f¹⁴ 5d² 6s² and an electronegativity near 1.3; its 2 outer-shell electrons drive its bonding. Under standard conditions it exists as a solid (a very high melting point); it melts near 2506 K (2232.9 °C), boils near 4876 K (4602.9 °C), has a density around 13.31 g/cm³.
It is widely used in Nuclear and Electronics / Semiconductors. It was first described by Coster & von Hevesy in 1923. See more trends in the visualization center.
Electron shells
Electrons per shell: 2 · 8 · 18 · 32 · 10 · 2
Main uses
- Nuclear
- Electronics / Semiconductors
Hazard
Compounds containing Hafnium
No compounds in this knowledge base contain Hafnium yet.
Data sources
Atomic mass uses IUPAC (CIAAW) standard atomic weights; the covalent radius is from Cordero et al. (2008). Verify on the RSC Periodic Table, PubChem and Wikipedia. Educational reference only.