Page 35 - Curriculum Visions Dynamic Book

Californium (Cf)
Element 98. Californium is an artificial metallic radioactive rare-earth element in the actinide series in the Periodic Table.
Discovery
Discovered at the University of California
by GlennT.Seaborg,Stanley G.Thompson, Albert Ghiorso and Kenneth Street in 1950 by bombarding curium-242 with helium ions.
Technology
It is used as a portable neutron source for the detection of gold or silver and also in moisture gauges for finding water and oil- bearing layers in oil wells.
Geology
Because it is an artificial element, it does not occur naturally.
Biology
It is a radioactive element and so is
a biological hazard. It is used as a very intense source of neutrons in medicine.
Key facts...
Name: Californium
Symbol: Cf
Atomic number: 98
Atomic weight: 251
Position in Periodic Table: inner transition
metal; period 7 (actinide series)
State at room temperature: solid
Colour: unknown
Density of solid: 15.1 g/cc
Melting point: 900°C
Boiling point: n/a
Origin of name: named after the state and
University of California
Shell pattern of electrons: 2–8–18–32–28–8–2
Blocks of quicklime.
The blocks expand and heat up if water is added.
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