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Element 63 - Europium (Eu) sound

From Europe; discovered 1896. Most reactive rare earth. This metal had virtually no practical use until the atomic age. But atom for atom europium can absorb mor neutrons than any other element, which makes it valuable in control rods for nuclear reactors.

Properties

Atomic Number: 63
Atomic Weight: 151.965
Electron Configuration (at ground state): 1s22s22p63s23p63d104s24p64d104f75s25p66s2
Oxidation States (Bold most stable): +3, +2
Boiling Point (K): 1800
Melting Point (K): 1095
Density (at 300K -- g/cm3): 5.24
Atomic Volume (at 300K -- cm3/mol) 28.9
Number of stable isotopes: 2
Mass Number (Bold naturally occurring) -- Half-Life -- Disintigration Type: 152 -- 13 years -- positron emission, orbital electron capture, beta particle (electron) emission
154 -- 8.5 years -- beta particle (electron) emission
Covalent Radius (Å): 1.85
Atomic Radius (Å): 1.99
First Ionization Potential (V): 5.67
Electronegativity (Pauling's): 1.2
Specific Heat Capacity (at 300K -- J g-1 K-1): 0.182
Heat of Vaporization (kJ/mol): 175.73
Heat of Fusion (kJ/mol): 10.46
Electrical Conductivity (at 293K for polycrystalline material -- 106 (ohms)-1 cm-1): 1.1
Thermal Conductivity (at 300K -- W m-1 K-1): 13.9
Crystal Structure: Cubic, body centered
Acid-Base Properties: Very basic