Protactinium

91
Pa
Gruppe
n/a
Periode
7
Block
f
Protonen
Elektronen
Neutronen
91
91
140
Generelle Eigenschaften
Ordnungszahl
91
Atommasse
231,03588
Massenzahl
231
Kategorie
Actinoide
Farbe
Silber
Radioaktiv
Ja
From the Greek protos meaning first
Kristallstruktur
Tetragonal zentriert
Geschichte
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.
Elektronen pro Schale
2, 8, 18, 32, 20, 9, 2
Elektronenkonfiguration
[Rn] 5f2 6d1 7s2
Pa
Protactinium is one of the rarest and most expensive naturally occurring elements
Physikalische Eigenschaften
Aggregatzustand
Fest
Dichte
15,37 g/cm3
Schmelzpunkt
1841,15 K | 1568 °C | 2854,4 °F
Siedepunkt
4300,15 K | 4027 °C | 7280,6 °F
Schmelzwärme
15 kJ/mol
Verdampfungswärme
470 kJ/mol
Spezifische Wärmekapazität
-
Häufigkeit in der Erdkruste
9,9×10-13%
Häufigkeit im Universum
n/a
Illustration
Danksagungen für Bilder: Images-of-elements
Illustration of protactinium
CAS-Nummer
7440-13-3
PubChem CID Number
n/a
Atomeigenschaften
Atomradius
163 pm
Kovalenter Radius
200 pm
Elektronegativität
1,5 (Pauling-Skala)
Ionisierungsenergie
5,89 eV
Molares Volumen
15,0 cm3/mol
Wärmeleitfähigkeit
0,47 W/cm·K
Oxidationszustände
3, 4, 5
Anwendung
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.
Protactinium is toxic and highly radioactive
Isotope
Stabile Isotope
-
Instabile Isotope
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