Kemiallinen merkki: Th
Järjestysluku: 90
Kategoria: aktinoidit
Ryhmä: n/a
Jakso: 7
Lohko: f
Moolimassa: 232,0381 g/mol
Elektronia kuorilla: 2, 8, 18, 32, 18, 10, 2
CAS-numero: 7440-29-1
Olomuoto: kiinteä
Tiheys: 11,7 kg/l (lähellä huoneenlämpöä)
Sulamispiste: 2115 K (1842 °C, 3348 °F)
Kiehumispiste: 5061 K (4788 °C, 8650 °F)
Kiderakenne: cubic face centered
Hapetusluvut: 4
Elektronegatiivisuus: 1,3 (Pauling-asteikko)
Nimen alkuperä: Thor
Nimen tarkoitus: the Norse god of thunder - the element was discovered in Norway
- is a silvery-white metal which is air-stable and retains its luster for several months
- when contaminated with the oxide, thorium slowly tarnishes in air, becoming gray and finally black
- is soft, very ductile, and can be cold-rolled, sw
- powdered thorium metal is often pyrophoric and should be carefully handled
- is used e,g, as an alloying agent in magnesium, in uranium-thorium age dating and as a radiation shield
- is found in small amounts in most rocks and soils, where it is about four times more abundant than uranium, and is about as common as lead
- decays very slowly compared to many other radioactive materials, and the alpha radiation emitted ca
- owning and handling small amounts of thorium, such as a gas mantle, is considered safe if care is taken not to ingest the thorium - lungs and other internal organs can be penetrated by alpha radiation
- exposure to an aerosol of thorium can lead to increased risk of cancers of the lung, pancreas and blood