Title: plutonium | Infoplease
Headings: plutonium
plutonium
Content: Plutonium-239 is produced in large quantities in nuclear reactors from uranium-238, an abundant but nonfissionable isotope. Uranium-238 absorbs neutrons emitted by the fission of uranium-235; uranium-239 is formed, which emits a beta particle and decays to neptunium-239; the neptunium-239 emits another beta particle, becoming plutonium-239. Once begun, the reaction proceeds spontaneously until the uranium fuel rods in the reactor are converted to a certain uranium-plutonium mixture. The rods are dissolved in acid and the plutonium separated by chemical means, especially by solvent extraction. Plutonium is important for its use in nuclear weapons and nuclear reactors. Plutonium-238 has been used to power scientific equipment in lunar exploration and implanted heart pacemakers (see pacemaker, artificial ). Plutonium is an extremely dangerous poison; it collects in the bones and interferes with the production of white blood cells.