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Plutonium (Pu)

A heavy, radioactive, manmade metallic element with atomic number 94. Its most important isotope is fissile plutonium-239, which is produced by neutron irradiation of uranium-238. It exists in only trace amounts in nature.

Page Last Reviewed/Updated Tuesday, March 09, 2021

Page Last Reviewed/Updated Tuesday, March 09, 2021