Протактиниум

91
Pa
Група
Нема одговор
Периода
7
блок
f
Protons
Electrons
Neutrons
91
91
140
Општи Својства
Атомски број
91
Атомска тежина
231,03588
Mass Number
231
Category
Актиноид
Color
Silver
Radioactive
Да
From the Greek protos meaning first
Кристална структура
Централно тетрагонално
History
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
Електронска конфигурација
[Rn] 5f2 6d1 7s2
Pa
Protactinium is one of the rarest and most expensive naturally occurring elements
Физички Својства
Фаза
Solid
Густина
15,37 g/cm3
Точка на топење
1841,15 K | 1568 °C | 2854,4 °F
Точка на вриење
4300,15 K | 4027 °C | 7280,6 °F
Топлина на топење
15 kJ/mol
Топлина на испарување
470 kJ/mol
Specific Heat Capacity
-
Abundance in Earth's crust
9,9×10-13%
Abundance in Universe
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Illustration
Кредити на слика: Images-of-elements
Illustration of protactinium
CAS Number
7440-13-3
PubChem CID Number
Нема одговор
Атомски Својства
Атомски полупречник
163 pm
Ковалентен полупречник
200 pm
Електронегативност
1,5 (Полингова скала)
Ionization Potential
5,89 eV
Atomic Volume
15,0 cm3/mol
Thermal Conductivity
0,47 W/cm·K
Oxidation States
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