Return to the Main CHEMystery Page.
Return to the Periodic Table of the Elements

Element 71 - Lutetium (Lu) sound

From Lutetia, the ancient name for Paris; discovered 1907; heaviest of the rare earths. Although rare-earth alloys such as misch metal are relatively cheap, pure lutetium is highly expensive. With many of its chemical and physical properties unknown, it has no practical value.

Properties

Atomic Number: 71
Atomic Weight: 174.967
Electron Configuration (at ground state): 1s22s22p63s23p63d104s24p64d104f145s25p65d16s2
Oxidation States (Bold most stable): +3
Boiling Point (K): 3668
Melting Point (K): 1936
Density (at 300K -- g/cm3): 9.84
Atomic Volume (at 300K -- cm3/mol) 17.8
Number of stable isotopes: 1
Number of natural radioactive isotopes: 1
Mass Number (Bold naturally occurring) -- Half-Life -- Disintigration Type: 176 -- 3.7 x 1010 years -- beta particle (electron) emission
Covalent Radius (Å): 1.56
Atomic Radius (Å): 1.75
First Ionization Potential (V): 5.43
Electronegativity (Pauling's): 1.27
Specific Heat Capacity (at 300K -- J g-1 K-1): 0.15
Heat of Vaporization (kJ/mol): 355
Heat of Fusion (kJ/mol): 18.6
Electrical Conductivity (at 293K for polycrystalline material -- 106 (ohms)-1 cm-1): 1.5
Thermal Conductivity (at 300K -- W m-1 K-1): 16.4
Crystal Structure: Hexagonal
Acid-Base Properties: Slightly basic