Californium: the essentials
Californium is a radioactive rare earth metal named after the state of California and the University of California (USA). Californium-252 is a strong neutron emitter and one microgram emits 170 million neutrons per minute, making it a biological hazard. It has a few specialised uses but only a few of its compounds are known.
- Name: californium
- Symbol: Cf
- Atomic number: 98
- Relative atomic mass (Ar): [ 251 ]
- Standard state: solid at 298 K
- Colour: unknown, but probably metallic and silvery white or grey in appearance
- Classification: Metallic
- Group in periodic table:
- Group name: Actinoid
- Period in periodic table: 7 (actinoid)
- Block in periodic table: f-block
- Electron shell structure: 2.8.18.32.28.8.2
- CAS Registry ID: 7440-71-3
Californium: historical information
Californium was produced by Ghiorso and others at the University of California, Berkeley, USA in 1950 who bombarded 242Cm with helium ions.
Californium around us Read more »
Californium has no biological role.
Californium is a synthetic element that is not present in the geosphere.
| Location | ppb by weight | ppb by atoms | Links |
|---|---|---|---|
| Universe | (no data) | (no data) | 
|
| Crustal rocks | (no data) | (no data) | 
|
| Human | (no data) ppb by weight | (no data) atoms relative to C = 1000000 | 
|
Physical properties Read more »
Density of solid: 15100 kg m-3
Molar volume: 16.50 cm3
Thermal conductivity: 10 (estimate) W m‑1 K‑1
Heat properties Read more »
Melting point: 1173 [900 °C (1652 °F)] K
Boiling point: (no data) K
Enthalpy of fusion: (no data) kJ mol-1
Crystal structure Read more »
The solid state structure of californium is: hcp (hexagonal close-packed).
Californium: orbital properties Read more »
Californium atoms have 98 electrons and the shell structure is 2.8.18.32.28.8.2. The ground state electronic configuration of neutral Californium is [Rn].5f10.7s2 and the term symbol of Californium is 5I8.
Pauling electronegativity: 1.3 (Pauling units)
First ionisation energy: 608 kJ mol‑1
Second ionisation energy: (no data) kJ mol‑1
Isolation
Isolation: coming soon!
Californium isotopes Read more »
| Isotope | Mass /Da |
Natural abund. (atom %) |
Nuclear spin (I) |
Nuclear magnetic moment (μ/μN) |
|---|---|---|---|---|
| nil |
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