98 Cf Californium [251]
Actinide
Californium 锎
[Rn] 5f¹⁰ 7s²
- Period 7
- Group —
- Block f
- Solid
Electron configuration
1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f¹⁴ 5s² 5p⁶ 5d¹⁰ 5f¹⁰ 6s² 6p⁶ 7s²
Orbital diagram (valence)
- Electrons per shell
- 2, 8, 18, 32, 28, 8, 2
- Unpaired electrons
- 4
- Zeff (Slater)
- 2.85
Properties
- Atomic weight
- [251]
- Electronegativity (Pauling)
- 1.3
- First ionization energy
- 607.9 kJ/mol
- Electron affinity
- no data
- Covalent radius
- no data
- van der Waals radius
- 245 pm
- Melting point
- 1173 K
- Boiling point
- no data
- Density
- no data
- Melting / boiling point
- 899.9 °C / —
- Common oxidation states
- +3
- Discovered
- 1950
Brackets give the mass number of the longest-lived isotope
Periodic trend
Data: PubChem periodic table (public domain); atomic weights are IUPAC abridged standard values; covalent radii from Cordero et al. (2008).