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Element 94 - Plutonium (Pu) sound

After Pluto, the planet beyond Neptune; discovered 1940. Plutonium was used, instead of uranium, in several of the first atomic bombs. In one of the codes of wartime physicists, plutonium was referred to as "copper"; copper itself had to be renamed "honest-to-God copper."

Properties

Atomic Number: 94
Atomic Weight: (244)
Electron Configuration (at ground state): 1s22s22p63s23p63d104s24p64d105s25p64f145d105f66s26p67s2
Oxidation States (Bold most stable): +6, +5, +4, +3
Boiling Point (K): 3505
Melting Point (K): 913
Density (at 300K -- g/cm3): 19.84
Atomic Volume (at 300K -- cm3/mol) 12.32
Number of natural radioactive isotopes: 1
Mass Number (Bold naturally occurring) -- Half-Life -- Disintigration Type: 238 -- 87.75 years -- alpha particle emission
239 -- 2.41 x 104 years -- alpha particle emission
240 -- 6.54 x 103 years -- alpha particle emission
242 -- 3.8 x 105 years -- alpha particle emission
244 -- 8.3 x 107 years -- alpha particle emission
Covalent Radius (Å): 1.08
Atomic Radius (Å): 1.51
First Ionization Potential (V): 6.06
Electronegativity (Pauling's): 1.28
Specific Heat Capacity (at 300K -- J g-1 K-1): 0.13
Electrical Conductivity (at 293K for polycrystalline material -- 106 (ohms)-1 cm-1): 0.7
Thermal Conductivity (at 300K -- W m-1 K-1): 6.74
Crystal Structure: Monoclinic
Acid-Base Properties: Amphoteric