Hafnium
Transition Metal
Hafnium (Hf) is a chemical element with atomic number 72, classified as a transition metal. At room temperature it is a solid. It was discovered in 1923 by Dirk Coster, George de Hevesy.
Properties
- Atomic number
- 72
- Atomic mass
- 178.49 u
- Category
- Transition Metal
- Group
- 4
- Period
- 6
- Block
- d-block
- Electron configuration
- [Xe] 4f¹⁴ 5d² 6s²
- Phase at STP
- Solid
- Density
- 13.31 g/cm³
- Melting point
- 2506 K (2232.8 °C)
- Boiling point
- 4876 K (4602.9 °C)
- Electronegativity
- 1.3
- Atomic radius
- 208 pm
- Ionization energy
- 6.825 eV
- Discovery
- 1923 · Dirk Coster, George de Hevesy
Common uses
Nuclear reactors, microprocessors, plasma cutting, superalloys
Did you know?
Excellent neutron absorber and used in nuclear submarine reactors.
Experiment with the elements
Hafnium doesn't form any compounds in our lab yet, but the periodic table sandbox lets you combine dozens of other real elements into real compounds — water, table salt, ammonia and many more — with their true chemical formulas.