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General Chemistry

Californium

Definition and meaning of Californium in chemistry.

Californium is a synthetic radioactive element with the symbol Cf and atomic number 98. It is a member of the actinide series and is notable for being an incredibly strong neutron emitter.

In more detail

Californium is a silvery white metal that tarnishes slowly in air and is highly reactive. It is synthesized by irradiating curium or berkelium with neutrons in specialized high-flux reactors, a process that yields only microscopic amounts of the element. The chemistry of californium is dominated by the +3 oxidation state, though a +2 state has been observed in certain solid compounds. Sitting deep within the f-block, californium represents the heaviest element that has been produced in sufficient quantities to have its macroscopic properties thoroughly studied. The intense neutron emission of its most common isotope makes it incredibly valuable for specialized applications, despite the extreme radiological hazards it presents.

Key facts

FieldGeneral Chemistry
SymbolCf
Atomic number98
Atomic mass[251] u
CategoryActinide
State at room temperatureSolid
Year discovered1950
Notable propertySpontaneously emits high levels of neutrons
Example

Californium-252 is used as a portable neutron source in oil well logging devices to determine the moisture and hydrocarbon content of boreholes.

Frequently asked questions

Why is californium so expensive to produce?

It requires prolonged irradiation of precursor materials in specialized nuclear reactors, followed by highly complex radiochemical separation processes.

Can californium be used to treat cancer?

Yes, the neutrons emitted by californium-252 have been used in targeted brachytherapy treatments for certain types of cervical and brain cancers.

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