Tulium

Kemiallinen merkki: Tm
Järjestysluku: 69
Kategoria: lantanoidit
Ryhmä: n/a
Jakso: 6
Lohko: f
Moolimassa: 168,93421 g/mol
Elektronia kuorilla: 2, 8, 18, 31, 8, 2
CAS-numero: 7440-30-4
Olomuoto: kiinteä
Tiheys: 9,32 kg/l (lähellä huoneenlämpöä)
Sulamispiste: 1818 K (1545 °C, 2813 °F)
Kiehumispiste: 2223 K (1950 °C, 3542 °F)
Kiderakenne: hexagonal
Hapetusluvut: 3
Elektronegatiivisuus: 1,25 (Pauling-asteikko)
Nimen alkuperä: Thule
Nimen tarkoitus: the name of Scandinavia in classical literature - the discoverer was Swedish
Faktoja:
- is the least abundant of the rare earths
- is an easily workable metal with a bright silvery-gray luster and can be cut by a knife
- has some corrosion resistance in dry air and good ductility
- naturally occurring thulium is made entirely of the stable isotope thulium-169
- as a rare and expensive, thulium does not have many practical applications
- has been used to create laser lights, but production costs have been too high for commercial use
- is never found in nature in pure form, but it is found in small quantities in minerals with other rare earths
- is used as interstellar money in the book Illegal Aliens, due to its rarity and lack of other uses
- has a low-to-moderate degree of acute toxicity and should be handled with care, and metallic thulium in dust form presents a fire and explosion hazard