About Californium:
- It is a silvery-white synthetic radioactive metal with the atomic number 98 on the periodic table.
- It was first synthesised in 1950 by a team at the University of California, Berkeley.
- The element is named after the American state of California and the university where it was discovered.
- It is not found naturally and is produced through nuclear reactions, specifically by bombarding curium with helium ions.
- Properties
- It is known for its intense radioactivity and is considered both valuable and hazardous.
- Californium is a member of the actinide series in the periodic table.
- The element’s most notable isotopes include Cf-251, which has a half-life of 898 years and is the most stable, and Cf-249 and Cf-250, which have shorter half-lives.
- Applications
- It is a very strong neutron emitter and is used in portable metal detectors for identifying gold and silver ores, to help identify water and oil layersin oil wells, and detect metal fatigue and stress in aeroplanes.
- It’s primary applications include starting nuclear reactors, optimising coal power plants, and treating certain cancers.
- It is also used in radiography, gold prospecting, and as a neutron source in various industrial applications.
Q1: What is radioactivity?
Radioactivity is the property of some unstable atoms (radionuclides) to spontaneously emit nuclear radiation, usually alpha particles or beta particles often accompanied by gamma-rays.
Source: The Californium that wasn’t — how ‘radioactive’ substance kept Bihar’s Gopalganj police on edge
Last updated on January, 2026
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