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Element 65 - Terbium (Tb) sound

From Ytterby, Sweden; discovered 1843; named after the town that also gave its name to three other elements; the rare earths ytterbium and erbium and the transitional metal yttrium. Like all rare earths, terbium in an impure state is pyrophoric--i.e., it bursts into flames when heated.

Properties

Atomic Number: 65
Atomic Weight: 158.9253
Electron Configuration (at ground state): 1s22s22p63s23p63d104s24p64d104f95s25p66s2
Oxidation States (Bold most stable): +3, +4
Boiling Point (K): 3500
Melting Point (K): 1629
Density (at 300K -- g/cm3): 8.23
Atomic Volume (at 300K -- cm3/mol) 19.2
Number of stable isotopes: 1
Mass Number (Bold naturally occurring) -- Half-Life -- Disintigration Type: 158 -- 1.2 x 103 years -- orbital electron capture, beta particle (electron) emission
160 -- 72.3 days -- beta particle (electron) emission
Covalent Radius (Å): 1.59
Atomic Radius (Å): 1.80
First Ionization Potential (V): 5.86
Electronegativity (Pauling's): 1.1
Specific Heat Capacity (at 300K -- J g-1 K-1): 0.18
Electrical Conductivity (at 293K for polycrystalline material -- 106 (ohms)-1 cm-1): 0.9
Thermal Conductivity (at 300K -- W m-1 K-1): 11.1
Crystal Structure: Hexagonal
Acid-Base Properties: Slightly basic