Berkelium (Bk) is chemical element 97, an actinide in the f-block, period 7 (PubChem).
- Atomic number: 97
- Symbol: Bk
- Group: none (f-block)
- Period: 7
- Atomic mass: 247.07031 u
- Electron configuration: [Rn]7s2 5f9
- Electronegativity (Pauling scale): 1.3
- Atomic radius (van der Waals): 244 pm
- Ionization energy: 6.23 eV
- Oxidation states: +4, +3
- Standard state: Solid
- Melting point: 1323 K
- Density: 14 g/cm³
- Chemical group: Actinide
- Year discovered: 1949