Protaktinium
91
Pa
Ryhmä
Ei saatavilla
Jakso
7
Lohko
f
Protonia
Elektronit
Neutronia
91
91
140
Yleiset ominaisuudet
Järjestysluku
91
Atomipaino
231,03588
Massaluku
231
Luokka
Aktinoidit
Väri
Hopea
Radioaktiivisuus
Kyllä
From the Greek protos meaning first
Kiderakenne
Tilakeskinen tetragoninen
Historia
In 1900, William Crookes isolated protactinium as an intensely radioactive material from uranium
Protactinium was first identified in 1913 by Kasimir Fajans and Oswald Helmuth Göhring in Germany.
A more stable isotope of protactinium was discovered in 1917 by Otto Hahn and Lise Meitner at the Kaiser Wilhelm Institute in Berlin.
Protactinium was first identified in 1913 by Kasimir Fajans and Oswald Helmuth Göhring in Germany.
A more stable isotope of protactinium was discovered in 1917 by Otto Hahn and Lise Meitner at the Kaiser Wilhelm Institute in Berlin.
Elektroneja elektronikuorilla
2, 8, 18, 32, 20, 9, 2
Orbitaalirakenne
[Rn] 5f2 6d1 7s2
Protactinium is one of the rarest and most expensive naturally occurring elements
Fyysiset ominaisuudet
Olomuoto
Kiinteä
Tiheys
15,37 g/cm3
Sulamispiste
1841,15 K | 1568 °C | 2854,4 °F
Kiehumispiste
4300,15 K | 4027 °C | 7280,6 °F
Sulamislämpö
15 kJ/mol
Höyrystymislämpö
470 kJ/mol
Ominaislämpökapasiteetti
-
Esiintyvyys maankuoressa
9,9×10-13%
Esiintyvyys maailmankaikkeudessa
Ei saatavilla
CAS-numero
7440-13-3
PubChem CID-numero
Ei saatavilla
Atomiominaisuudet
Atomisäde
163 pm
Kovalenttisäde
200 pm
Elektronegatiivisuus
1,5 (Paulingin asteikko)
Ionisoitumispotentiaali
5,89 eV
Moolitilavuus
15,0 cm3/mol
Lämmönjohtavuus
0,47 W/cm·K
Hapetusluvut
3, 4, 5
Käyttö
Owing to its scarcity, high radioactivity and high toxicity, there are currently no uses for protactinium outside of scientific research.
With the advent of highly sensitive mass spectrometers, an application of 231Pa as a tracer in geology and paleoceanography has become possible.
Protactinium-231 combined with the thorium-230 can be used to date marine sediments.
With the advent of highly sensitive mass spectrometers, an application of 231Pa as a tracer in geology and paleoceanography has become possible.
Protactinium-231 combined with the thorium-230 can be used to date marine sediments.
Protactinium is toxic and highly radioactive
Isotooppi
Vakaat isotoopit
-Epävakaat isotoopit
212Pa, 213Pa, 214Pa, 215Pa, 216Pa, 217Pa, 218Pa, 219Pa, 220Pa, 221Pa, 222Pa, 223Pa, 224Pa, 225Pa, 226Pa, 227Pa, 228Pa, 229Pa, 230Pa, 231Pa, 232Pa, 233Pa, 234Pa, 235Pa, 236Pa, 237Pa, 238Pa, 239Pa, 240Pa