Which element is named after the U.S. state of California?

Which element is named after the U.S. state of California? Californium is the answer.

Californium, symbol Cf and atomic number 98, was first produced in 1950 at the University of California Radiation Laboratory in Berkeley. The discovery team bombarded curium-242 with alpha particles in a 60-inch cyclotron, creating tiny amounts of the new element.

The name honors both California and the University of California. The researchers originally considered the naming traditions of nearby transuranium elements, but chose the state because the work was carried out there. Only about 5,000 atoms were produced in the first experiment, and they quickly decayed.

Californium is a synthetic, highly radioactive actinide; no significant natural deposits exist. Its isotope californium-252 is especially useful because it releases neutrons through spontaneous fission. Those neutrons have applications in neutron radiography, some reactor start-up systems, and certain treatments or industrial instruments. A common mix-up is confusing Californium with berkelium: both were discovered at Berkeley, but berkelium is element 97 and is named directly after Berkeley.