Protactini
91
Pa
Grup
n/a
Període
7
Bloc
f
Protons
Electrons
Neutrons
91
91
140
Propietats Generals
Nombre atòmic
91
Massa atòmica
231,03588
Nombre de massa
231
Categoria
Actínids
Color
Plata
Radioactiu
Sí
From the Greek protos meaning first
Estructura cristal·lina
Tetragonal centrada
Història
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.
Electrons per capa
2, 8, 18, 32, 20, 9, 2
Configuració electrònica
[Rn] 5f2 6d1 7s2
Protactinium is one of the rarest and most expensive naturally occurring elements
Propietats Físiques
Fase
Sòlid
Densitat
15,37 g/cm3
Punt de fusió
1841,15 K | 1568 °C | 2854,4 °F
Punt d'ebullició
4300,15 K | 4027 °C | 7280,6 °F
Entalpia de fusió
15 kJ/mol
Entalpia de vaporització
470 kJ/mol
Capacitat tèrmica específica
-
Abundància a l'escorça terrestre
9,9×10-13%
Abundància a l'univers
n/a
Número CAS
7440-13-3
Número CID de PubChem
n/a
Propietats Atòmiques
Radi atòmic
163 pm
Radi covalent
200 pm
Electronegativitat
1,5 (Escala de Pauling)
Potencial d'ionització
5,89 eV
Volum atòmic
15,0 cm3/mol
Conductivitat tèrmica
0,47 W/cm·K
Estats d'oxidació
3, 4, 5
Aplicacions
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
Isòtops
Isòtops estables
-Isòtops inestables
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