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crystal structurePlutonium • Actinide Rare Earth

Symbol: Pu
Date of Discovery: 1940
Name Origin: the planet Pluto
Appearance: silver-white
Discoverer: G.T. Seaborg
Obtained From: uranium ores, man-made

Melting Point: 913 K
Boiling Point: 3503 K
Density[kg/m3]: 19816
Molar Volume: 12.29 × 10-6 m3/mol
Protons/Electrons: 94
Neutrons: 150
Shell Structure: 2,8,18,32,24,8,2
Electron Configuration: [Rn]5f67s2
Oxidation State: 6,5,4,3
Named Crystal Structure: monoclinic

Named after the planet Pluto, plutonium was the second transuranium element of the actinide series discovered. Its appearance is silver-white, though it tarnishes to yellow when slightly oxidized. The isotope 239Pu has a half-life over 20,000 years; one kilogram produces over 20 million kilowatt hours of heat energy. Applications of plutonium include use as an explosive ingredient in nuclear weapons and as a key material in the development of nuclear power. Because of the energy given off by alpha decay, a large piece of plutonium is warm to the touch. Although plutonium occurs naturally in trace amounts, most existing plutonium has been created from fissile activity, particularly in nuclear power reactors.


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