• Class: Trans-Uranium AcTinides
• Period: 7
• IUPAC group: 3
• Traditional: IIIa

• Discovered in: 1950 by Thompson et. al.
• Origin of name: The US state of California
• Historical or alternate name:

Silvery metal. Resists alkalis. Reacts with acids, Oxygen and steam.

• Atmosphere: ~0.0 ppm
• Primitive mantle: ~0.0 ppm
• Sea water: ~0.0 ppm
• Metallic meteorite: ~0.0 ppm
• ConTinental crust: ~0.0 ppm
• Solar photosphere: ~0.0 log of abundance
• Oceanic crust: ~0.0 ppm
• Solar system: ~0.0 relative to Si=1.0e6

   Hazards

Radioactive..

• Lower:
• Upper:

Californium Physical Properties

 Transitional Data

• State: Solid
• Density: 15.1 g/cm3

 Molar enthalpy

• Atomization: 175.0 kJ mol-1
• Fusion: kJ mol-1
• Vaporization: kJ mol-1

 Transition points

• MelTing point: 1173.0 K
• Boiling point: K
• Critical temperature: K

 Molar properties

• Atomic weight: 251.0796 g/mole
• Molar volume: 16.50 cm3 mol-1

 Crystal structure sequence

double-hex-close-packed <873 K < face-centered-cubic < 998 K < face-centered-cubic < melTing point

 Thermodynamics

• State: solid
  • Enthalpy 0
  • Gibbs function 0
  • Entropy
  • Heat Capacity 25.98

 Miscellaneous physical

• Electrical resistivity: µ-ohms/cm
• Debye temperature: K
• Thermal conductivity: W / m / K
• Coefficient of linear expansion: Coef. per K
• Mass magnetic susceptibility:
• X-ray diffraction mass absorption coefficients:
• CuK: (µ/p)/cm2 g-1
• MoK: (µ/p)/cm2 g-1

Californium Chemical Properties

 Chemical basics:

• Oxidation states: +3 +4
• Molecular wt: 251.0796 g/mole

 Radii

• Covalent: pm
• Atomic: 186.0 pm
• Van der Waals: pm

 Ions:

• ion: +3 pm 95.0
• ion: +4 pm 82.1

 Covalent bonds

 Effective nuclear charge

• Slater: 1.65
• Clementi:
• Froese-Fischer:

 Electronegativity

• Pauling: 1.3
• Allred-Rochow:

 Standard reactions

Californium Nuclear Properties

• Known 12
• Listed 7

• Known 242 - 264
• Listed 248 - 254

• % Occ.:Natural
• Mossbauer NRA:
• Nuclear spin/Quantum no.:
• Radioisotopes:
  • Half-life: 334.00 days
  • Decay mode: alpha, S.F.
  • Source:
• Notes

• % Occ.:Natural
• Mossbauer NRA:
• Nuclear spin/Quantum no.: 9/2
• Radioisotopes:
  • Half-life: 351.00 years
  • Decay mode: alpha, S.F.
  • Source:
• Notes

• % Occ.:Natural
• Mossbauer NRA:
• Nuclear spin/Quantum no.:
• Radioisotopes:
  • Half-life: 13.10 years
  • Decay mode: alpha, S.F.
  • Source:
• Notes

• % Occ.:Natural
• Mossbauer NRA:
• Nuclear spin/Quantum no.: 1/2
• Radioisotopes:
  • Half-life: 898.00 years
  • Decay mode: alpha,
  • Source:
• Notes

• % Occ.:Natural
• Mossbauer NRA:
• Nuclear spin/Quantum no.:
• Radioisotopes:
  • Half-life: 2.64 years
  • Decay mode: alpha, S.F.
  • Source:
• Notes

• % Occ.:Natural
• Mossbauer NRA:
• Nuclear spin/Quantum no.:
• Radioisotopes:
  • Half-life: 17.80 days
  • Decay mode: Beta- alpha,
  • Source:
• Notes

• % Occ.:Natural
• Mossbauer NRA:
• Nuclear spin/Quantum no.:
• Radioisotopes:
  • Half-life: 60.50 days
  • Decay mode: S.F.. E.C.
  • Source:
• Notes

• Isotope 251Cross-section 2100±1000 barns

Californium Energy Properties

Electrons

• Ground state electron configuration: [Rn] 5f10 7s2
• Electron affinity: kJ mol-1
• Filling orbitals:

 Ionization energies

 Atomic energy levels