“californium”的意思、由来-百科全书

californium

chemical element

(Cf),

synthetic chemical element of the actinoid series of the periodic table, atomic number 98. Not occurring in nature, californium (as the isotope californium-245) was discovered (1950) by Stanley G. Thompson, Kenneth Street, Jr., Albert Ghiorso, and Glenn T. Seaborg at the University of California, Berkeley, as a product resulting from the helium-ion bombardment of curium-242 (atomic number 96) in the 60-inch cyclotron.

All californium isotopes are radioactive; the long-lived isotopes are produced from berkelium-249 or from californium-249. They are: californium-249 (360-year half-life); californium-250 (13-year half-life); californium-251 (800-year half-life); and californium-252 (2.65-year half-life). These isotopes have been used in tracer amounts for investigating the chemistry of californium (which exhibits an oxidation state of +3 in acidic aqueous solution) and for preparing microgram quantities of compounds such as the oxychloride CfOCl, the oxide Cf₂O₃, and the trichloride CfCl₃. There is some evidence for a +2 state also. Metallic californium has not yet been prepared.

Californium-252, because 3 percent of its decay occurs by spontaneous fission, is industrially and medically important as a very intense point source of neutrons. One microgram releases 170,000,000 neutrons per minute.

atomic number

stablest isotope

251

oxidation state

electronic config.

【Rn】5f ¹⁰7s²

词条	californium
释义	californium chemical element (Cf), synthetic chemical element of the actinoid series of the periodic table, atomic number 98. Not occurring in nature, californium (as the isotope californium-245) was discovered (1950) by Stanley G. Thompson, Kenneth Street, Jr., Albert Ghiorso, and Glenn T. Seaborg at the University of California, Berkeley, as a product resulting from the helium-ion bombardment of curium-242 (atomic number 96) in the 60-inch cyclotron. All californium isotopes are radioactive; the long-lived isotopes are produced from berkelium-249 or from californium-249. They are: californium-249 (360-year half-life); californium-250 (13-year half-life); californium-251 (800-year half-life); and californium-252 (2.65-year half-life). These isotopes have been used in tracer amounts for investigating the chemistry of californium (which exhibits an oxidation state of +3 in acidic aqueous solution) and for preparing microgram quantities of compounds such as the oxychloride CfOCl, the oxide Cf₂O₃, and the trichloride CfCl₃. There is some evidence for a +2 state also. Metallic californium has not yet been prepared. Californium-252, because 3 percent of its decay occurs by spontaneous fission, is industrially and medically important as a very intense point source of neutrons. One microgram releases 170,000,000 neutrons per minute. atomic number 98 stablest isotope 251 oxidation state +3 electronic config. 【Rn】5f ¹⁰7s²
随便看	Chapultepec Chapultepec Zoological Park char charabanc characin character Characteristics of oxide glasses Characteristics of three typical lubricants character piece character writer charactonym charade charadriiform Charadrius Charan Singh Charbonnages de France Charbonneau, Jean Charbonneau, Robert charcoal charcoal drawing Charcot, Jean-Baptiste-Étienne-Auguste Charcot, Jean-Martin Charcot-Marie-Tooth disease chard Chardin, Jean