Polonium

Kemiallinen merkki: Po
Järjestysluku: 84
Kategoria: puolimetallit
Ryhmä: 16
Jakso: 6
Lohko: p
Moolimassa: (209) g/mol
Elektronia kuorilla: 2, 8, 18, 32, 18, 6
CAS-numero: 7440-08-6
Olomuoto: kiinteä
Tiheys: 9,196 kg/l (lähellä huoneenlämpöä)
Sulamispiste: 527 K (254 °C, 489 °F)
Kiehumispiste: 1235 K (962 °C, 1764 °F)
Kiderakenne: cubic
Hapetusluvut: 4, 2
Elektronegatiivisuus: 2,0 (Pauling-asteikko)
Nimen alkuperä: Polonia
Nimen tarkoitus: the Latin name for Poland; the native land of the discoverer, Marie Curie
Faktoja:
- a rare and highly radioactive metalloid
- is chemically similar to bismuth and tellurium, and it occurs in uranium ores
- is unstable; all isotopes of polonium are radioactive
- is very volatile; it will almost completely vaporize at room temperatures
- has 27 known isotopes - polonium-210 is the most widely available
- is tentatively called 'Radium F'
- by mass, polonium-210 is around 250,000 times more toxic than hydrogen cyanide
- the main hazard is its intense radioactivity (as an alpha emitter), which makes it very difficult to handle safely: one gram of Po will self-heat to a temperat
- when it is mixed or alloyed with beryllium, polonium can be a neutron source