Californium (Cf)
Californium is the 98th element in the periodic table and has a symbol of Cf and atomic number of 98. It has an atomic weight of (251) and a mass number of 237. Californium has ninety-eight protons and one hundred thirty-nine neutrons in its nucleus, and ninety-eight electrons in seven shells. It is located in group Actinides, period seven and block f of the periodic table. Radioactive metallic transuranic element. Belongs to actinoid series. Cf-251 has a half life of about 700 years. Nine isotopes are known. Cf-252 is an intense Neutron source, which makes it an intense Neutron source and gives it a use in Neutron activation analysis and a possible use as a radiation source in medicine. First produced by Glenn T. Seaborg and associates in 1950.
| Atomic Number | 98 |
|---|---|
| Atomic Weight | 251 |
| Mass Number | 237 |
| Group | |
|---|---|
| Period | 7 |
| Block | f |
| Protons | 98 p+ |
|---|---|
| Neutrons | 139 n0 |
| Electrons | 98 e- |
Physical Properties
| Atomic Radius | |
|---|---|
| Molar Volume | |
| Covalent Radius | |
| Metallic Radius | |
| Ionic Radius | |
| Crystal Radius | |
| Van der Waals Radius | |
| Density |
Chemical Properties
| Energy | |
|---|---|
| Proton Affinity | |
| Electron Affinity | |
| Ionization Energy | |
| Heat of Vaporization | |
| Heat of Fusion | |
| Heat of Formation | |
| Electrons | |
| Electron Shells | 2, 8, 18, 32, 28, 8, 2 |
 | |
| Valence Electrons | 2 ⓘ |
 | |
| Electron Configuration | [Rn] 5f10 7s2ⓘ 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 5f10 7s2 |
  | |
| Oxidation States | 2, 3, 4, 5 |
| Electronegativity | |
| Electrophilicity Index | |
| States of Matter | |
| Phase | Solid |
| Gas Phase | |
| Boiling Point | |
| Melting Point | |
| Critical Pressure | |
| Critical Temperature | |
| Triple Point | |
| Visual | |
Californium is a Colorless. Cf has a CPK of #ffffff, Jmol of #a136d4, and MOLCAS GV of #a136d4. The Appearance of Element 98 is silvery. | |
| Color | Colorless
|
| Appearance | silvery |
| Refractive Index | |
| Thermodynamic Properties | |
| Thermal Conductivity | |
| Thermal Expansion | |
| Molar Heat Capacity | |
| Specific Heat Capacity | |
| Heat Capacity Ratio (Adiabatic Index) | |
| Electrical Properties | |
| Type | |
| Electrical Conductivity | |
| Electrical Resistivity | |
| Superconducting Point | |
| Magnetism | |
| Type | |
| Magnetic Susceptibility (Mass) | |
| Magnetic Susceptibility (Molar) | |
| Magnetic Susceptibility (Volume) | |
| Magnetic Ordering | |
| Curie Point | |
| Neel Point | |
| Structure | |
The lattice angles of Californium are π/2, π/2, 2 π/3. | |
| Crystal Structure | Simple Hexagonal () |
| Lattice Constant | |
| Lattice Angles | π/2, π/2, 2 π/3 |
| Mechanical Properties | |
| Hardness | |
| Bulk Modulus | |
| Shear Modulus | |
| Young's Modulus | |
| Poisson Ratio | |
| Speed of Sound | |
| Classification | |
The Glawe Number of Californium is 42. The Mendeleev Number of Cf is 32. The Pettifor Number of Element 98 is 39. The Goldschmidt Class of Californium (Cf) is synthetic. | |
| Category | Actinides, Actinides |
| CAS Group | |
| IUPAC Group | |
| Glawe Number | 42 |
| Mendeleev Number | 32 |
| Pettifor Number | 39 |
| Geochemical Class | |
| Goldschmidt Class | synthetic |
Other
The Dipole Polarizability of Californium is 122 plus or minus 20 a₀. The Allotropes of Cf is . The Neutron Cross Section of Element 98 is 2900. The Quantum Numbers of Californium (Cf) is 5I8. The Space Group of Californium is 194 (P63/mmc).
| Gas Basicity | |
|---|---|
| Dipole Polarizability | |
| C6 Dispersion Coefficient | |
| Allotropes | |
| Neutron Cross Section | 2,900
|
| Neutron Mass Absorption | |
| Quantum Numbers | 5I8 |
| Space Group | 194 (P63/mmc) |
Isotopes of Californium
| Stable Isotopes | 0 |
|---|---|
| Unstable Isotopes | 20 |
| Natural Isotopes | 0 |
237Cf
| Mass Number | 237 |
|---|---|
| Neutron Number | 139 |
| Relative Atomic Mass | |
| G-Factor | |
| Abundance | |
| Radioactivity | ☢️ Radioactive |
| Half Life | 0.8 ± 0.2 s
|
| Spin | 5/2 |
| Quadrupole Moment | |
| Discovery Year | 1995 |
| Parity | + |
| Decay Mode | Intensity |
|---|---|
| α (α emission) | 70% |
| SF (spontaneous fission) | 30% |
| β+ (β+ decay; β+ = ϵ + e+) |
238Cf
| Mass Number | 238 |
|---|---|
| Neutron Number | 140 |
| Relative Atomic Mass | |
| G-Factor | 0
|
| Abundance | |
| Radioactivity | ☢️ Radioactive |
| Half Life | 21.1 ± 1.3 ms
|
| Spin | 0 |
| Quadrupole Moment | 0
|
| Discovery Year | 1995 |
| Parity | + |
| Decay Mode | Intensity |
|---|---|
| SF (spontaneous fission) | 97.5% |
| α (α emission) | 2.5% |
239Cf
| Mass Number | 239 |
|---|---|
| Neutron Number | 141 |
| Relative Atomic Mass | |
| G-Factor | |
| Abundance | |
| Radioactivity | ☢️ Radioactive |
| Half Life | 28 ± 2 s
|
| Spin | 5/2 |
| Quadrupole Moment | |
| Discovery Year | 1981 |
| Parity | + |
| Decay Mode | Intensity |
|---|---|
| α (α emission) | 65% |
| β+ (β+ decay; β+ = ϵ + e+) |
240Cf
| Mass Number | 240 |
|---|---|
| Neutron Number | 142 |
| Relative Atomic Mass | |
| G-Factor | 0
|
| Abundance | |
| Radioactivity | ☢️ Radioactive |
| Half Life | 40.3 ± 0.9 s
|
| Spin | 0 |
| Quadrupole Moment | 0
|
| Discovery Year | 1970 |
| Parity | + |
| Decay Mode | Intensity |
|---|---|
| α (α emission) | 98.5% |
| SF (spontaneous fission) | 1.5% |
| β+ (β+ decay; β+ = ϵ + e+) |
241Cf
| Mass Number | 241 |
|---|---|
| Neutron Number | 143 |
| Relative Atomic Mass | |
| G-Factor | |
| Abundance | |
| Radioactivity | ☢️ Radioactive |
| Half Life | 2.35 ± 0.18 m
|
| Spin | 7/2 |
| Quadrupole Moment | |
| Discovery Year | 1970 |
| Parity | - |
| Decay Mode | Intensity |
|---|---|
| β+ (β+ decay; β+ = ϵ + e+) | |
| α (α emission) | 15% |
242Cf
| Mass Number | 242 |
|---|---|
| Neutron Number | 144 |
| Relative Atomic Mass | |
| G-Factor | 0
|
| Abundance | |
| Radioactivity | ☢️ Radioactive |
| Half Life | 3.49 ± 0.15 m
|
| Spin | 0 |
| Quadrupole Moment | 0
|
| Discovery Year | 1967 |
| Parity | + |
| Decay Mode | Intensity |
|---|---|
| α (α emission) | 61% |
| β+ (β+ decay; β+ = ϵ + e+) | 39% |
| SF (spontaneous fission) | 0.014% |
243Cf
| Mass Number | 243 |
|---|---|
| Neutron Number | 145 |
| Relative Atomic Mass | |
| G-Factor | |
| Abundance | |
| Radioactivity | ☢️ Radioactive |
| Half Life | 10.8 ± 0.3 m
|
| Spin | 1/2 |
| Quadrupole Moment | 0
|
| Discovery Year | 1967 |
| Parity | + |
| Decay Mode | Intensity |
|---|---|
| β+ (β+ decay; β+ = ϵ + e+) | 86% |
| α (α emission) | 14% |
244Cf
| Mass Number | 244 |
|---|---|
| Neutron Number | 146 |
| Relative Atomic Mass | |
| G-Factor | 0
|
| Abundance | |
| Radioactivity | ☢️ Radioactive |
| Half Life | 19.5 ± 0.5 m
|
| Spin | 0 |
| Quadrupole Moment | 0
|
| Discovery Year | 1956 |
| Parity | + |
| Decay Mode | Intensity |
|---|---|
| α (α emission) | 75% |
| ϵ (electron capture) | 25% |
245Cf
| Mass Number | 245 |
|---|---|
| Neutron Number | 147 |
| Relative Atomic Mass | |
| G-Factor | |
| Abundance | |
| Radioactivity | ☢️ Radioactive |
| Half Life | 45 ± 1.5 m
|
| Spin | 1/2 |
| Quadrupole Moment | 0
|
| Discovery Year | 1956 |
| Parity | + |
| Decay Mode | Intensity |
|---|---|
| β+ (β+ decay; β+ = ϵ + e+) | 64.7% |
| α (α emission) | 35.3% |
246Cf
| Mass Number | 246 |
|---|---|
| Neutron Number | 148 |
| Relative Atomic Mass | |
| G-Factor | 0
|
| Abundance | |
| Radioactivity | ☢️ Radioactive |
| Half Life | 35.7 ± 0.5 h
|
| Spin | 0 |
| Quadrupole Moment | 0
|
| Discovery Year | 1951 |
| Parity | + |
| Decay Mode | Intensity |
|---|---|
| α (α emission) | 100% |
| SF (spontaneous fission) | 2.4% |
| ϵ (electron capture) |
247Cf
| Mass Number | 247 |
|---|---|
| Neutron Number | 149 |
| Relative Atomic Mass | |
| G-Factor | |
| Abundance | |
| Radioactivity | ☢️ Radioactive |
| Half Life | 3.11 ± 0.03 h
|
| Spin | 7/2 |
| Quadrupole Moment | |
| Discovery Year | 1954 |
| Parity | + |
| Decay Mode | Intensity |
|---|---|
| ϵ (electron capture) | 99.965% |
| α (α emission) | 0.035% |
248Cf
| Mass Number | 248 |
|---|---|
| Neutron Number | 150 |
| Relative Atomic Mass | |
| G-Factor | 0
|
| Abundance | |
| Radioactivity | ☢️ Radioactive |
| Half Life | 333.5 ± 2.8 d
|
| Spin | 0 |
| Quadrupole Moment | 0
|
| Discovery Year | 1954 |
| Parity | + |
| Decay Mode | Intensity |
|---|---|
| α (α emission) | 100% |
| SF (spontaneous fission) | 0.0029% |
249Cf
| Mass Number | 249 |
|---|---|
| Neutron Number | 151 |
| Relative Atomic Mass | |
| G-Factor | |
| Abundance | |
| Radioactivity | ☢️ Radioactive |
| Half Life | 351 ± 2 y
|
| Spin | 9/2 |
| Quadrupole Moment | |
| Discovery Year | 1954 |
| Parity | - |
| Decay Mode | Intensity |
|---|---|
| α (α emission) | 100% |
| SF (spontaneous fission) | 5% |
250Cf
| Mass Number | 250 |
|---|---|
| Neutron Number | 152 |
| Relative Atomic Mass | |
| G-Factor | 0
|
| Abundance | |
| Radioactivity | ☢️ Radioactive |
| Half Life | 13.08 ± 0.09 y
|
| Spin | 0 |
| Quadrupole Moment | 0
|
| Discovery Year | 1954 |
| Parity | + |
| Decay Mode | Intensity |
|---|---|
| α (α emission) | 99.923% |
| SF (spontaneous fission) | 0.077% |
251Cf
| Mass Number | 251 |
|---|---|
| Neutron Number | 153 |
| Relative Atomic Mass | |
| G-Factor | |
| Abundance | |
| Radioactivity | ☢️ Radioactive |
| Half Life | 898 ± 44 y
|
| Spin | 1/2 |
| Quadrupole Moment | 0
|
| Discovery Year | 1954 |
| Parity | + |
| Decay Mode | Intensity |
|---|---|
| α (α emission) | 100% |
| SF (spontaneous fission) |
252Cf
| Mass Number | 252 |
|---|---|
| Neutron Number | 154 |
| Relative Atomic Mass | |
| G-Factor | 0
|
| Abundance | |
| Radioactivity | ☢️ Radioactive |
| Half Life | 2.645 ± 0.008 y
|
| Spin | 0 |
| Quadrupole Moment | 0
|
| Discovery Year | 1954 |
| Parity | + |
| Decay Mode | Intensity |
|---|---|
| α (α emission) | 96.8972% |
| SF (spontaneous fission) | 3.1028% |
253Cf
| Mass Number | 253 |
|---|---|
| Neutron Number | 155 |
| Relative Atomic Mass | |
| G-Factor | |
| Abundance | |
| Radioactivity | ☢️ Radioactive |
| Half Life | 17.81 ± 0.08 d
|
| Spin | 7/2 |
| Quadrupole Moment | |
| Discovery Year | 1954 |
| Parity | + |
| Decay Mode | Intensity |
|---|---|
| β− (β− decay) | 99.69% |
| α (α emission) | 0.31% |
254Cf
| Mass Number | 254 |
|---|---|
| Neutron Number | 156 |
| Relative Atomic Mass | |
| G-Factor | 0
|
| Abundance | |
| Radioactivity | ☢️ Radioactive |
| Half Life | 60.5 ± 0.2 d
|
| Spin | 0 |
| Quadrupole Moment | 0
|
| Discovery Year | 1955 |
| Parity | + |
| Decay Mode | Intensity |
|---|---|
| SF (spontaneous fission) | 99.69% |
| α (α emission) | 0.31% |
| 2β− (double β− decay) |
255Cf
| Mass Number | 255 |
|---|---|
| Neutron Number | 157 |
| Relative Atomic Mass | |
| G-Factor | |
| Abundance | |
| Radioactivity | ☢️ Radioactive |
| Half Life | 85 ± 18 m
|
| Spin | 7/2 |
| Quadrupole Moment | |
| Discovery Year | 1981 |
| Parity | + |
| Decay Mode | Intensity |
|---|---|
| β− (β− decay) | 100% |
| SF (spontaneous fission) | |
| α (α emission) |
256Cf
| Mass Number | 256 |
|---|---|
| Neutron Number | 158 |
| Relative Atomic Mass | |
| G-Factor | 0
|
| Abundance | |
| Radioactivity | ☢️ Radioactive |
| Half Life | 12.3 ± 1.2 m
|
| Spin | 0 |
| Quadrupole Moment | 0
|
| Discovery Year | 1980 |
| Parity | + |
| Decay Mode | Intensity |
|---|---|
| SF (spontaneous fission) | 100% |
| α (α emission) | |
| 2β− (double β− decay) |
History
Californium was discovered by Stanley G. Thompson, Kenneth Street, Jr., Albert Ghiorso and Glenn T. Seaborg in 1950 at the University of California, Berkeley. It was produced by the bombardment of curium with alpha particles. Californium was isolated in macro quantities for the first time by Burris Cunningham and Stanley Thompson in 1958. Named after California and the University of California
| Discoverers | G.T.Seaborg, S.G.Tompson, A.Ghiorso, K.Street Jr. |
|---|---|
| Discovery Location | United States |
| Discovery Year | 1950 |
| Etymology (Name Origin) | Named after the state and University of California. |
| Pronunciation | kal-eh-FOR-ni-em (English) |
Californium is harmful due to its radioactivity
Californium is produced in nuclear reactors and particle accelerators
Uses
Californium is used as a portable neutron source for discovery of metals such as gold or silver by on-the-spot activation analysis. Neutrons from californium are employed as a treatment of certain cervical and brain cancers where other radiation therapy is ineffective. Neutron moisture gauges use californium-252 to find water and petroleum layers in oil wells. It has no significant commercial applications.
Sources
Made by bombarding curium with helium ions.
| Abundance | |
|---|---|
| Abundance in Earth's crust | |
| Natural Abundance (Oceans) | |
| Natural Abundance (Human Body) | 0 %
|
| Natural Abundance (Meteor) | 0 %
|
| Natural Abundance (Sun) | 0 %
|
| Abundance in Universe | 0 %
|
Nuclear Screening Constants
Also Known As
- Cf
- element 98
- 98Cf
Translations
- Frenchcalifornium
- GermanCalifornium
- Amharicካሊፎርኒየም
- Arabicكاليفورنيوم
- AzerbaijaniKalifornium
- BelarusianКаліфорній
- Banglaক্যালিফোর্নিয়াম
- Bosniankalifornij
- Catalancaliforni
- CorsicanCaliforniu
- Czechkalifornium
- ChuvashКалифорни
- WelshCalifforniwm
- Danishcalifornium
- Greekκαλιφόρνιο
- Esperantokaliforniumo
- Spanishcalifornio
- Estoniankalifornium
- Basquekalifornio
- Persianکالیفرنیم
- Finnishkalifornium
- FriulianCaliforni
- IrishCalafoirniam
- GalicianCalifornio
- ManxCalifornium
- Hakka Chinesecalifornium
- Hebrewקליפורניום
- Fiji HindiCalifornium
- Croatiankalifornij
- Haitian CreoleKalifònyòm
- Hungariankalifornium
- Armenianկալիֆոռնիում
- Interlinguacalifornium
- Indonesiankalifornium
- Idokalifornio
- Italiancalifornio
- Japaneseカリホルニウム
- Lojbanjinmrkaliforni
- JavaneseKalifornium
- Korean캘리포늄
- KomiКалифорний
- Latincalifornium
- LuxembourgishCalifornium
- LigurianCalifornio
- Lithuaniankalifornis
- Latviankalifornijs
- Malayalamകാലിഫോർണിയം
- Marathiकॅलिफोर्नियम
- Western MariКалифорний
- MalayKalifornium
- Burmeseကာလီဖိုနီယမ်
- Dutchcalifornium
- Norwegian Nynorskcalifornium
- Occitancalifòrni
- Polishkaliforn
- Portuguesecalifórnio
- QuechuaKalifornyu
- Romaniancaliforniu
- Russianкалифорний
- Sanskritकालिफोर्नियम
- YakutКалифорниум
- Siciliancaliforniu
- Serbo-CroatianKalifornijum
- Slovakkalifornium
- Sloveniankalifornij
- Albaniankaliforniumi
- Serbianкалифорнијум
- Saterland FrisianCalifornium
- Swedishcalifornium
- Thaiแคลิฟอร์เนียม
- Turkishkaliforniyum
- Uyghurكالىفورنىي
- Ukrainianкаліфорній
- Urduکیلیفورنیئم
- VepsKalifornii
- Vietnamesecaliforni
- WarayCalifornyo
- KalmykКалифорниүм
- YorubaKalifọ́rníọ̀m
- Chinese锎
- Norwegian Bokmålcalifornium
- CebuanoCalifornyo
- Macedonianкалифорниум
- Central Kurdishکالیفۆرنیۆم
- Western Panjabiکیلیفورنیم
- BretonKaliforniom
- German (Switzerland)Californium
- English (Canada)Californium
- English (United Kingdom)californium
- Portuguese (Brazil)califórnio
- Cantonese鉲
- Odiaକାଲିଫର୍ମିଅମ
- Gujaratiકેલિફોર્નીયમ
- Tamilகலிபோர்னியம்
- TatarКалифорний
- Bulgarianкалифорний
- PiedmonteseCalifòrni
- Newariक्यालिफोर्नियम
- Kannadaಕ್ಯಾಲಿಫೋರ್ನಿಯಮ್
- KazakhКалифорний
- Belarusian (Taraskievica orthography)Каліфорн
- UzbekKaliforniy
- AromanianCaliforniu
- Nepaliक्यालिफोर्नियम
- KyrgyzКалифорний
- Teluguకాలిఫోర్నియం
- Maltesekalifornju
- Chinese (Simplified)锎
- Hindiकैलीफोर्नियम
- Scottish GaelicCalafòrnium
- Paliक्यालिफोर्नियम
- cdoCalifornium
- Min Nan ChineseCalifornium
- FaroeseKalifornium
- AsturianCalifornio
- LimburgishCalifornium
- Bhojpuriकैलिफोर्नियम
- Chinese (Traditional)鉲
- Chinese (Macao SAR China)鉲
- Chinese (China)锎
- Chinese (Hong Kong SAR China)鉲
- Chinese (Malaysia)锎
- Chinese (Singapore)锎
- Chinese (Taiwan)鉲
- Lingua Franca Novacalifornio
- TagalogKalipornyo
- AfrikaansKalifornium
- kbpKalɩfɔrnɩyɔm
- Literary Chinese鐦
- Northern FrisianKalifornium
- Volapükkalifornin
- oloKalifornii
- TajikКалифорний
- Georgianკალიფორნიუმი
- Mongolianкалифорни
- Wu Chinese锎
- SardinianCalifòrniu
- SwahiliKaliforni
- Moroccan Arabicكاليفورنيوم
- BashkirКалифорний
- Egyptian Arabicكاليفورنيوم
- Pashtoکاليفورنيوم
- CornishKaliforniom
- BalineseKalifornium
- ZuluUmNgcalife
