98
Californium
Atomic Number98
Atomic Mass251 u
CategoryActinide
State at Room TempSolid
Year Discovered1950
About Californium
Named for California and the university that created it. One of the few elements sold commercially: a single microgram costs tens of dollars, and californium-252 is a ferocious neutron emitter used to kickstart nuclear reactors, scan oil wells, and detect explosives and gold. Only two reactors in the world produce it, in Russia and the United States.
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