Lutetium

Symbol: Lu
Atomic number: 71
Category: lanthanides
Group: n/a
Period: 6
Block: f
Atomic weight: 174.967 g/mol
Electrons per shell: 2, 8, 18, 32, 9, 2
CAS number: 7439-94-3
Phase: solid
Density: 9.841 kg/dm³ (near room temperature)
Melting point: 1925 K (1652 °C, 3006 °F)
Boiling point: 3675 K (3402 °C, 6156 °F)
Crystal structure: hexagonal
Oxidation states: 3
Electronegativity: 1.27 (Pauling scale)
Name's origin: Lutetia
Name's meaning: the Latin name of Paris; the discoverer was French
Facts:
- is a silvery white corrosion-resistant trivalent metal that is relatively stable in air
- is the heaviest and hardest of the rare earth elements
- has the highest melting point of any lanthanide, probably related to the lanthanide contraction
- is very expensive to obtain in useful quantities and therefore it has very few commercial uses
- stable lutetium can be used as catalysts in petroleum cracking in refineries and can also be used in alkylation, hydrogenation, and polymerization
- lutetium-176 has been used to date the age of meteorites
- was proposed with names aldebaranium, neoytterbium, cassiopium and lutecium
- found with almost all other rare-earth metals but never by itself, lutetium is very difficult to separate
- is one of the most expensive metals, costing about six times as much as gold
- is regarded as having a low degree of toxicity but it and especially its compounds should be handled with care nonetheless
- metal dust of this element is a fire and explosion hazard
- plays no biological role in the human body