Protactinium (Pa)

General Properties

Symbol Pa
Atomic Number 91
Atomic Weight 231.03588
Group
(Actinoids)
Solid, Conductor, Actinide, Radioactive, Natural
Period 7
Block f

Physical Properties

Density 15.4 g/cm3
Atomic Volume 15.0 cm3/mole
Atomic Radius 1.61 angstroms
Covalent Radius --
Crust Abundance 9.9E-13%
Crystal Structure Orthorhombic
Color Silver

Energy

Electronegativity 1.5 (Pauling Scale)
Electron Affinity --
1st Ionization Energy 568 kJ/mol
Specific Heat Capacity J g−1 K−1
Thermal Conductivity 47.0 W·m−1·K−1

Electrons & Oxidation

Oxidation States +5,4
Electrons Per Shell 2 8 18 32 20 9 2
Electron Configuration [Rn] 5f2 6d1 7s2
1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 5f2 6d1 7s2
Orbital Diagram
1s
↿⇂
2s
↿⇂
2p
↿⇂
↿⇂
↿⇂
3s
↿⇂
3p
↿⇂
↿⇂
↿⇂
3d
↿⇂
↿⇂
↿⇂
↿⇂
↿⇂
4s
↿⇂
4p
↿⇂
↿⇂
↿⇂
4d
↿⇂
↿⇂
↿⇂
↿⇂
↿⇂
4f
↿⇂
↿⇂
↿⇂
↿⇂
↿⇂
↿⇂
↿⇂
5s
↿⇂
5p
↿⇂
↿⇂
↿⇂
5d
↿⇂
↿⇂
↿⇂
↿⇂
↿⇂
5f
↿ 
↿ 
 
 
 
 
 
6s
↿⇂
6p
↿⇂
↿⇂
↿⇂
6d
↿ 
 
 
 
 
6f
 
 
 
 
 
 
 
7s
↿⇂
7p
 
 
 
7d
 
 
 
 
 
7f
 
 
 
 
 
 
 

Nuclear

Radioactive Yes
Half Life 32788 y
Lifetime 47279.y
Decay Alpha Emission

Media

Planetary Bohr Model of Protactinium (Pa)
Lewis Dot Diagram of Protactinium (Pa)
Description
Very rare, silvery-white, extremely radioactive metal.
Uses
It has no significant commercial applications.
Sources
Does not occur in nature. Found among fission products of uranium, thorium, and plutonium.
Pronounciation (English)
PRO-tak-tin-eh-em

Translations

Afrikaans Protaktinium
Aragonese Protactinio
العربية بروتكتنيوم
Armãneashte Protactiniumu
asturianu Protactiniu
azərbaycan dili Protaktinium
български Протактиний
বাংলা প্রোটেক্টিনিয়াম
brezhoneg Protaktiniom
bosanski Protactinijum, ²Protaktinij
Byelorussian Пратактыній
Cebuano Protactinyo
čeština Protaktinium
Chuvash Протактини
Cymraeg Protactini
dansk Protactinium
Deutsch Protaktinium
Ελληνικά Πρωτακτινιο
English Protactinium
esperanto Protaktinio
español Protactínio
eesti Protaktiinium
euskara Protaktinioa
فارسی پروتاکتینیم
suomi Protaktinium
føroyskt Protaktinium
français Protactinium
furlan Protoatini
West-Frysk Protactinium
Gaeilge Prótachtainiam
Gàidhlig Pròtactainiam
galego Protactinio
ગુજરાતી પ્રોટૅક્ટિનિયમનો
Gaelg Protaghtinnium
Hakka Chinese Phù (鏷)
עברית פרוטקטיניום
हिन्दी प्रोटैक्टीनियम
hrvatski Protaktinij
magyar Protaktínium
հայերեն Պրոտակտինիում
Indonesia Protaktinium
íslenska Protaktín
italiano Protoattinio
日本語 プロトアクチニウム
ქართული პროტაქტინიუმი
کٲشُر Protaktin
қазақ тілі Протактиний
한국어 프로트악티늄 or 프로탁티늄
Kurdish Proaktinyûm
Komi Протактиний
kernewek Protoactynyum
кыргызча Протактиний
Latin Protactinium
Lëtzebuergesch Protaktinium
Lombard Protuatíni
lingála Potinu?
lietuvių Protaktinis
latviešu Protaktīnijs
Mari Протактиний
Maori Protactinium
македонски Протактиниум
മലയാളം പ്രൊട്ടക്റ്റിനിയം
монгол Протактини
Мокшан Протактини
Bahasa Melayu Protaktinium
Malti Protaktinjum, ²Protoattinju
Nahuatl Protactinio
Nederlands Protactinium
norsk Protactinium
Occitan Protactini
ирон Протактиний
polski Proaktyn
português Protacnídio
Runasimi Protaktinyu
română Protactiniu
русский Протактиний
slovenčina Protaktinium
slovenščina Protaktinij
Samoan Protaktinimi
Samogitian Pruotaktėnis
shqip Protaktin, ²Protactiniumi
српски Протоактинијум
Southern Sotho Proaktiniamo
svenska Protaktinium
Kiswahili Protaktini
தமிழ் புரொட்டக்டினியம்
Tajik Протактиний
ไทย โพรแทกทิเนียม
Türkçe Protaktinyum
ئۇيغۇرچە پروتاكتىنىي
українська Протактиній
o‘zbek Protaktiniy
Tiếng Việt Protactini
Võro Protaktiinium
中文

History

Discovered In
1913
Discovered By
Otto Hahn, Lise Meitner, Frederick Soddy, John Cranston
Discovered At
Germany, England
Word Origin
From the Greek word "protos" meaning "first"