Protactinium

Kemiallinen merkki: Pa
Järjestysluku: 91
Kategoria: aktinoidit
Ryhmä: n/a
Jakso: 7
Lohko: f
Moolimassa: 231,03588 g/mol
Elektronia kuorilla: 2, 8, 18, 32, 20, 9, 2
CAS-numero: 7440-13-3
Olomuoto: kiinteä
Tiheys: 15,37 kg/l (lähellä huoneenlämpöä)
Sulamispiste: 1841 K (1568 °C, 2854 °F)
Kiehumispiste: 4300 K (4027 °C, 7280 °F)
Kiderakenne: orthorhombic
Hapetusluvut: 2, 3, 4, 5
Elektronegatiivisuus: 1,5 (Pauling-asteikko)
Nimen alkuperä: protoactinium
Nimen tarkoitus: means 'first actinium' as its first product is the element actinium
Faktoja:
- is a silver metallic element that belongs to the actinoid group, with a bright metallic luster that it retains for some time in the air
- due to its scarcity, high radioactivity, and toxicity, there are currently no uses for protactinium ou
- twenty-nine radioisotopes of protactinium have been characterized, with the most stable being protactinium-231 with a half life of 32760 years
- is both toxic and highly radioactive
- requires precautions similar to those used when handling plutonium
- its most common ore, pitchblende, contains about 0,1 ppm of protactinium