Protaktinij

91
Pa
Skupina
n/a
Perioda
7
Blok
f
Protons
Electrons
Neutrons
91
91
140
General Properties
Vrstno število
91
Atomska teža
231,03588
Mass Number
231
Kategorija
Aktinoidi
Barva
Silver
Radioactive
Da
From the Greek protos meaning first
Kristalna struktura
Telesno centrirana tetragonalna
Zgodovina
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.
Electrons per shell
2, 8, 18, 32, 20, 9, 2
Razporeditev elektronov
[Rn] 5f2 6d1 7s2
Pa
Protactinium is one of the rarest and most expensive naturally occurring elements
Physical Properties
Faza snovi
Trdnina
Gostota
15,37 g/cm3
Tališče
1841,15 K | 1568 °C | 2854,4 °F
Vrelišče
4300,15 K | 4027 °C | 7280,6 °F
Talilna toplota
15 kJ/mol
Izparilna toplota
470 kJ/mol
Toplotna kapaciteta
-
Abundance in Earth's crust
9,9×10-13%
Abundance in Universe
n/a
Illustration
Zasluge za slike: Images-of-elements
Illustration of protactinium
CAS Number
7440-13-3
PubChem CID Number
n/a
Atomic Properties
Atomski polmer
163 pm
Kovalentni polmer
200 pm
Elektronegativnost
1,5 (Paulingova lestvica)
Ionization Potential
5,89 eV
Atomic Volume
15,0 cm3/mol
Toplotna prevodnost
0,47 W/cm·K
Oksidacijska stanja
3, 4, 5
Applications
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
Isotopes
Stable Isotopes
-
Unstable Isotopes
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