Protactinium (Pa)

Protactinium is the 91st element in the periodic table and has a symbol of Pa and atomic number of 91. It has an atomic weight of (231.03588) and a mass number of 231. Protactinium has ninety-one protons and one hundred forty neutrons in its nucleus, and ninety-one electrons in seven shells. It is located in group Actinides, period seven and block f of the periodic table. Radioactive metallic element, belongs to the actinoids. The most stable isotope, Pa-231 has a half-life of 2.43*10^4 years. At least 10 other radioactive isotopes are known. No practical applications are known. Discovered in 1917 by Lise Meitner and Otto Hahn.

Atomic Number	91
Atomic Weight	231.03588
Mass Number	231

Group
Period	7
Block	f

Protons	91 p⁺
Neutrons	140 n⁰
Electrons	91 e^-

Animated Bohr Model of Pa (Protactinium)

Physical Properties

Atomic Radius	180 pm 285 pm
Molar Volume	15 cm³/mol
Covalent Radius	169 pm 138 pm 129 pm 200 pm
Metallic Radius
Ionic Radius	104 pm 90 pm 101 pm 78 pm 91 pm 95 pm 119.9 pm
Crystal Radius	118 pm 104 pm 115 pm 92 pm 105 pm 109 pm 133.9 pm
Van der Waals Radius	243 pm 264 pm 342.4 pm
Density	15.4 g/cm³

Chemical Properties

Energy

Proton Affinity
Electron Affinity
Ionization Energy	5.89 eV/particle 11.9 eV/particle 19 eV/particle 30.9 eV/particle 44.3 eV/particle 72 eV/particle 85.1 eV/particle 98.9 eV/particle 111 eV/particle 137 eV/particle 153 eV/particle 187 eV/particle 203 eV/particle 292 eV/particle 316 eV/particle 342 eV/particle 369 eV/particle 395 eV/particle 423 eV/particle 460 eV/particle 488 eV/particle 518 eV/particle 546 eV/particle 690 eV/particle 720 eV/particle 760 eV/particle 790 eV/particle 880 eV/particle 920 eV/particle 1,020 eV/particle 1,060 eV/particle 1,150 eV/particle 1,220 eV/particle 1,300 eV/particle 1,370 eV/particle 1,450 eV/particle 1,520 eV/particle 1,600 eV/particle 1,670 eV/particle 1,760 eV/particle 1,830 eV/particle 1,910 eV/particle 2,000 eV/particle 2,060 eV/particle 2,130 eV/particle 2,483 eV/particle 2,550 eV/particle 2,620 eV/particle 2,696 eV/particle 2,766 eV/particle 2,837 eV/particle 2,968 eV/particle 3,040 eV/particle 3,119 eV/particle 3,193 eV/particle 3,488 eV/particle 3,558 eV/particle 3,637 eV/particle 3,709 eV/particle 4,077 eV/particle 4,161 eV/particle 4,370 eV/particle 4,454 eV/particle 7,181 eV/particle 7,341 eV/particle 7,510 eV/particle 7,690 eV/particle 7,870 eV/particle 8,040 eV/particle 8,410 eV/particle 8,590 eV/particle 8,780 eV/particle 8,960 eV/particle 9,460 eV/particle 9,620 eV/particle 9,790 eV/particle 9,950 eV/particle 11,100 eV/particle 11,280 eV/particle 11,660 eV/particle 11,840 eV/particle 24,660 eV/particle 25,080 eV/particle 25,540 eV/particle 25,970 eV/particle 30,230 eV/particle 30,800 eV/particle 31,520 eV/particle 31,971.6 eV/particle 126,296.6 eV/particle 128,507 eV/particle

Heat of Vaporization	481.2 kJ/mol
Heat of Fusion	16.7 kJ/mol
Heat of Formation	563 kJ/mol
Electrons

Electron Shells	2, 8, 18, 32, 20, 9, 2

Valence Electrons	2 ⓘ

Electron Configuration	[Rn] 5f² 6d¹ 7s²ⓘ 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f¹⁴ 5d¹⁰ 6p⁶ 5f² 6d¹ 7s²

Oxidation States	2, 3, 4, 5
Electronegativity	0.12149 1.5
Electrophilicity Index
States of Matter

Phase	Solid
Gas Phase
Boiling Point
Melting Point	1,845.15 K
Critical Pressure
Critical Temperature
Triple Point
Visual
Protactinium is a Silver. Pa has a CPK of #ffffff, Jmol of #00a1ff, and MOLCAS GV of #00a1ff. The Appearance of Element 91 is bright, silvery metallic luster.
Color	Silver #ffffff #00a1ff #00a1ff
Appearance	bright, silvery metallic luster
Refractive Index
Thermodynamic Properties
Thermal Conductivity
Thermal Expansion
Molar Heat Capacity
Specific Heat Capacity
Heat Capacity Ratio (Adiabatic Index)
Electrical Properties
Type	Conductor
Electrical Conductivity	5.6 MS/m
Electrical Resistivity	0.00000018 m Ω
Superconducting Point	1.41 K
Magnetism
Type	paramagnetic
Magnetic Susceptibility (Mass)	0.0000000325 m³/Kg
Magnetic Susceptibility (Molar)	0.000000007509 m³/mol
Magnetic Susceptibility (Volume)	0.0004995
Magnetic Ordering
Curie Point
Neel Point
Structure
The Crystal Structure of Protactinium is TET. The lattice constant of Pa is 3.92 Å. The lattice angles of Element 91 are π/2, π/2, π/2.
Crystal Structure	Centered Tetragonal (TET)
Lattice Constant	3.92 Å
Lattice Angles	π/2, π/2, π/2
Mechanical Properties

Hardness
Bulk Modulus
Shear Modulus
Young's Modulus
Poisson Ratio
Speed of Sound
Classification
The Glawe Number of Protactinium is 35. The Mendeleev Number of Pa is 18. The Pettifor Number of Element 91 is 46. The Geochemical Class of Protactinium (Pa) is U/Th decay series. The Goldschmidt Class of Protactinium is litophile.
Category	Actinides, Actinides
CAS Group
IUPAC Group
Glawe Number	35
Mendeleev Number	18
Pettifor Number	46
Geochemical Class	U/Th decay series
Goldschmidt Class	litophile

Other

The Dipole Polarizability of Protactinium is 154 plus or minus 20 a₀. The Allotropes of Pa is . The Neutron Cross Section of Element 91 is 200. The Quantum Numbers of Protactinium (Pa) is 4K11/2. The Space Group of Protactinium is 139 (I4/mmm).

Gas Basicity
Dipole Polarizability	154 ± 20 a₀
C6 Dispersion Coefficient
Allotropes
Neutron Cross Section	200
Neutron Mass Absorption
Quantum Numbers	4K11/2
Space Group	139 (I4/mmm)

Isotopes of Protactinium

Stable Isotopes	0
Unstable Isotopes	31
Natural Isotopes	1

²¹¹Pa

Mass Number	211
Neutron Number	120
Relative Atomic Mass	211.023674036 ± 0.000074581 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	6 ± 3 ms
Spin	9/2
Quadrupole Moment
Discovery Year	2006
Parity	-

Decay Mode	Intensity
α (α emission)	100%
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)
p (proton emission)

²¹²Pa

Mass Number	212
Neutron Number	121
Relative Atomic Mass	212.023184819 ± 0.000094047 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	5.8 ± 1.9 ms
Spin	3
Quadrupole Moment
Discovery Year	1997
Parity	+

Decay Mode	Intensity
α (α emission)	100%

²¹³Pa

Mass Number	213
Neutron Number	122
Relative Atomic Mass	213.021099644 ± 0.000061374 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	7.4 ± 2.4 ms
Spin	9/2
Quadrupole Moment
Discovery Year	1995
Parity	-

Decay Mode	Intensity
α (α emission)	100%

²¹⁴Pa

Mass Number	214
Neutron Number	123
Relative Atomic Mass	214.020891055 ± 0.00008718 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	17 ± 3 ms
Spin	7
Quadrupole Moment
Discovery Year	1995
Parity	+

Decay Mode	Intensity
α (α emission)	100%

²¹⁵Pa

Mass Number	215
Neutron Number	124
Relative Atomic Mass	215.019113955 ± 0.000088513 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	14 ± 2 ms
Spin	9/2
Quadrupole Moment
Discovery Year	1979
Parity	-

Decay Mode	Intensity
α (α emission)	100%

²¹⁶Pa

Mass Number	216
Neutron Number	125
Relative Atomic Mass	216.019134633 ± 0.000026459 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	105 ± 12 ms
Spin	5
Quadrupole Moment
Discovery Year	1972
Parity	+

Decay Mode	Intensity
α (α emission)	100%
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)

²¹⁷Pa

Mass Number	217
Neutron Number	126
Relative Atomic Mass	217.018309024 ± 0.000013417 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	3.8 ± 0.2 ms
Spin	9/2
Quadrupole Moment
Discovery Year	1968
Parity	-

Decay Mode	Intensity
α (α emission)	100%
β⁻ (β⁻ decay)

²¹⁸Pa

Mass Number	218
Neutron Number	127
Relative Atomic Mass	218.020021133 ± 0.000019158 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	108 ± 5 us
Spin	8
Quadrupole Moment
Discovery Year	1979
Parity	-

Decay Mode	Intensity
α (α emission)	100%

²¹⁹Pa

Mass Number	219
Neutron Number	128
Relative Atomic Mass	219.019949909 ± 0.000074831 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	56 ± 9 ns
Spin	9/2
Quadrupole Moment
Discovery Year	2005
Parity	-

Decay Mode	Intensity
α (α emission)	100%
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)

²²⁰Pa

Mass Number	220
Neutron Number	129
Relative Atomic Mass	220.021769753 ± 0.000015732 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	0.85 ± 0.06 us
Spin	1
Quadrupole Moment
Discovery Year	2005
Parity	-

Decay Mode	Intensity
α (α emission)	100%
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)

²²¹Pa

Mass Number	221
Neutron Number	130
Relative Atomic Mass	221.021873393 ± 0.000063746 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	5.9 ± 1.7 us
Spin	9/2
Quadrupole Moment
Discovery Year	1983
Parity	-

Decay Mode	Intensity
α (α emission)	100%

²²²Pa

Mass Number	222
Neutron Number	131
Relative Atomic Mass	222.023687064 ± 0.000092975 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	3.8 ± 0.2 ms
Spin	1
Quadrupole Moment
Discovery Year	1970
Parity	-

Decay Mode	Intensity
α (α emission)	100%

²²³Pa

Mass Number	223
Neutron Number	132
Relative Atomic Mass	223.023980414 ± 0.000081193 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	5.3 ± 0.3 ms
Spin	9/2
Quadrupole Moment
Discovery Year	1970
Parity	-

Decay Mode	Intensity
α (α emission)	100%
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)

²²⁴Pa

Mass Number	224
Neutron Number	133
Relative Atomic Mass	224.025617286 ± 0.000008145 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	844 ± 19 ms
Spin	5
Quadrupole Moment
Discovery Year	1958
Parity	-

Decay Mode	Intensity
α (α emission)	100%
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)

²²⁵Pa

Mass Number	225
Neutron Number	134
Relative Atomic Mass	225.026147927 ± 0.000087887 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	1.71 ± 0.1 s
Spin	5/2
Quadrupole Moment
Discovery Year	1958
Parity	-

Decay Mode	Intensity
α (α emission)	100%

²²⁶Pa

Mass Number	226
Neutron Number	135
Relative Atomic Mass	226.027948217 ± 0.000012037 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	1.8 ± 0.2 m
Spin	1
Quadrupole Moment
Discovery Year	1949
Parity	-

Decay Mode	Intensity
α (α emission)	74%
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	26%

²²⁷Pa

Mass Number	227
Neutron Number	136
Relative Atomic Mass	227.028803586 ± 0.000007797 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	38.3 ± 0.3 m
Spin	5/2
Quadrupole Moment
Discovery Year	1948
Parity	-

Decay Mode	Intensity
α (α emission)	85%
ϵ (electron capture)	15%

²²⁸Pa

Mass Number	228
Neutron Number	137
Relative Atomic Mass	228.031050758 ± 0.000004659 Da
G-Factor	1.1666666666667 ± 0.16666666666667
Abundance
Radioactivity	☢️ Radioactive
Half Life	22 ± 1 h
Spin	3
Quadrupole Moment
Discovery Year	1948
Parity	+

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	98.15%
α (α emission)	1.85%

²²⁹Pa

Mass Number	229
Neutron Number	138
Relative Atomic Mass	229.032095585 ± 0.000003521 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	1.55 ± 0.04 d
Spin	5/2
Quadrupole Moment
Discovery Year	1949
Parity	+

Decay Mode	Intensity
ϵ (electron capture)	99.51%
α (α emission)	0.49%

²³⁰Pa

Mass Number	230
Neutron Number	139
Relative Atomic Mass	230.034539717 ± 0.000003261 Da
G-Factor	1 ± 0.1
Abundance
Radioactivity	☢️ Radioactive
Half Life	17.4 ± 0.5 d
Spin	2
Quadrupole Moment
Discovery Year	1948
Parity	-

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	92.2%
β⁻ (β⁻ decay)	7.8%
α (α emission)	0.0032%

²³¹Pa

Mass Number	231
Neutron Number	140
Relative Atomic Mass	231.0358825 ± 0.000001901 Da
G-Factor	1.3266666666667 ± 0.013333333333333
Abundance	100
Radioactivity	☢️ Radioactive
Half Life	32.65 ± 0.2 ky
Spin	3/2
Quadrupole Moment	-1.72 ± 0.05
Discovery Year	1918
Parity	-

Decay Mode	Intensity
α (α emission)	100%
SF (spontaneous fission)	3%
24Ne (heavy cluster emission)	13.4%
23F	9.9%

²³²Pa

Mass Number	232
Neutron Number	141
Relative Atomic Mass	232.038590205 ± 0.000008206 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	1.32 ± 0.02 d
Spin	2
Quadrupole Moment
Discovery Year	1949
Parity	-

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
ϵ (electron capture)

²³³Pa

Mass Number	233
Neutron Number	142
Relative Atomic Mass	233.040246535 ± 0.000001433 Da
G-Factor	2.6666666666667 ± 0.46666666666667
Abundance
Radioactivity	☢️ Radioactive
Half Life	26.975 ± 0.013 d
Spin	3/2
Quadrupole Moment	-3 ± 0.4
Discovery Year	1938
Parity	-

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

²³⁴Pa

Mass Number	234
Neutron Number	143
Relative Atomic Mass	234.043305555 ± 0.000004395 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	6.7 ± 0.05 h
Spin	4
Quadrupole Moment
Discovery Year	1913
Parity	+

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

²³⁵Pa

Mass Number	235
Neutron Number	144
Relative Atomic Mass	235.045399 ± 0.000015 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	24.4 ± 0.2 m
Spin	3/2
Quadrupole Moment
Discovery Year	1950
Parity	-

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

²³⁶Pa

Mass Number	236
Neutron Number	145
Relative Atomic Mass	236.048668 ± 0.000015 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	9.1 ± 0.1 m
Spin	1
Quadrupole Moment
Discovery Year	1963
Parity

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ SF (β⁻-delayed fission)	6%

²³⁷Pa

Mass Number	237
Neutron Number	146
Relative Atomic Mass	237.051023 ± 0.000014 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	8.7 ± 0.2 m
Spin	1/2
Quadrupole Moment	0
Discovery Year	1954
Parity	+

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

²³⁸Pa

Mass Number	238
Neutron Number	147
Relative Atomic Mass	238.054637 ± 0.000017 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	2.28 ± 0.09 m
Spin	3
Quadrupole Moment
Discovery Year	1968
Parity	-

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ SF (β⁻-delayed fission)	2.6%

²³⁹Pa

Mass Number	239
Neutron Number	148
Relative Atomic Mass	239.05726 ± 0.00021 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	1.8 ± 0.5 h
Spin	1/2
Quadrupole Moment	0
Discovery Year	1995
Parity	+

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

²⁴⁰Pa

Mass Number	240
Neutron Number	149
Relative Atomic Mass	240.061203 ± 0.000215 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life
Spin	3
Quadrupole Moment
Discovery Year
Parity	+

Decay Mode	Intensity
β⁻ (β⁻ decay)

²⁴¹Pa

Mass Number	241
Neutron Number	150
Relative Atomic Mass	241.064134 ± 0.000322 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life
Spin	1/2
Quadrupole Moment	0
Discovery Year
Parity	+

Decay Mode	Intensity
β⁻ (β⁻ decay)

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. From the Greek protos meaning first

Discoverers	Fredrich Soddy, John Cranston, Otto Hahn, Lise Meitner
Discovery Location	England/France
Discovery Year	1917
Etymology (Name Origin)	Greek: proto and actinium (parent of actinium); it forms actinium when it radioactively decays.
Pronunciation	PRO-tak-tin-eh-em (English)

Protactinium is toxic and highly radioactive

Protactinium is one of the rarest and most expensive naturally occurring elements

Uses

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. It has no significant commercial applications.

Sources

Does not occur in nature. Found among fission products of uranium, thorium, and plutonium.

Abundance
Abundance in Earth's crust	0.0000014 mg/kg
Natural Abundance (Oceans)	0.00000000005 mg/L
Natural Abundance (Human Body)	0 %
Natural Abundance (Meteor)
Natural Abundance (Sun)
Abundance in Universe	0 %

Nuclear Screening Constants

Also Known As

Pa
element 91
91Pa
protoactinium
brevium

Translations

Frenchprotactinium
Norwegian Bokmålprotactinium
GermanProtactinium
Italianprotoattinio
Spanishprotactinio
Norwegian Nynorskprotactinium
Danishprotactinium
Hungarianprotaktínium
Polishprotaktyn
Amharicፕሮታክቲኒየም
Arabicبروتكتينيوم
AzerbaijaniProtaktinium
BelarusianПратактыній
Bulgarianпротактиний
Banglaপ্রোটেক্টিনিয়াম
Bosnianprotaktinij
Catalanprotoactini
CorsicanProtoattiniu
Czechprotaktinium
ChuvashПротактини
WelshProtactiniwm
Greekπρωτακτίνιο
Esperantoprotaktinio
Estonianprotaktiinium
Basqueprotaktinio
Persianپروتاکتینیم
Finnishprotaktinium
FriulianProtoatini
Irishprótachtainiam
Galicianprotactinio
ManxProtaghtinnium
Hakka Chineseprotactinium
Hebrewפרוטקטיניום
Fiji HindiProtactinium
Croatianprotaktinij
Armenianպրոտակտինիում
Interlinguaprotactinium
Indonesianprotaktinium
Idoprotaktinio
Japaneseプロトアクチニウム
Lojbanjinmrproktini
JavaneseProtaktinium
Kannadaಪ್ರೊಟಾಕ್ಟಿನಿಯಮ್
Korean프로탁티늄
KomiПротактиний
Latinprotactinium
LuxembourgishProtactinium
LigurianProtoattinio
Lithuanianprotaktinis
Latvianprotaktīnijs
Malayalamപ്രൊട്ടക്റ്റിനിയം
Marathiप्रोटॅक्टिनियम
Western MariПротактиний
MalayProtaktinium
Burmeseပရိုတက်တီနီယမ်
Dutchprotactinium
Occitanprotactini
Western Panjabiپروٹیکٹینیم
Portugueseprotactínio
QuechuaProtaktinyu
Romanianprotactiniu
Russianпротактиний
YakutПротактиниум
Sicilianprutuattiniu
ScotsProtactinium
Serbo-CroatianProtaktinijum
Slovakprotaktínium
Slovenianprotaktinij
Serbianпротактинијум
Saterland FrisianProtaktinium
Swedishprotaktinium
Thaiโพรโทแอกทิเนียม
Turkishprotaktinyum
Uyghurپروتاكتىنىي
Ukrainianпротактиній
Urduprotactinium
VepsProtaktinii
Vietnameseprotactini
WarayProtactinyo
KalmykПротактиниум
YorubaProtaktiníọ̀m
Chinese镤
Georgianპროტაქტინიუმი
CebuanoProtactinyo
Central Kurdishپرۆتەکتینیۆم
Macedonianпротактиниум
BretonProtaktiniom
Gujaratiપ્રોટેક્ટિનીયમ
Low GermanProtactinium
Odiaପ୍ରୋଟାକ୍ଟିଅମ
Tamilபிரொடாக்டினியம்
TatarПротактиний
PiedmonteseProtoactini
Hindiप्रोटैक्टीनियम
KazakhПротактиний
Newariप्रोट्याक्टिनियम
Cantonese鏷
Belarusian (Taraskievica orthography)Пратактын
AlbanianProtaktini
Chinese (China)镤
Chinese (Simplified)镤
Chinese (Traditional)鏷
Chinese (Hong Kong SAR China)鏷
Chinese (Taiwan)鏷
AromanianProtactiniu
UzbekProtaktiniy
KyrgyzПротактиний
LimburgishProtactinium
Sanskritप्रोट्याक्टिनियम
Malteseprotaktinju
Scottish GaelicProtactinium
Teluguప్రొటాక్టీనియం
cdoProtactinium
Min Nan ChineseProtactinium
AsturianProtactiniu
Nepaliप्रोट्याक्टिनियम
Paliप्रोट्याक्टिनियम
Bhojpuriप्रोटैक्टिनियम
Tibetanཔུ་རོ་ཊེག་ཊི་ནིམ།
Chinese (Macao SAR China)鏷
Chinese (Malaysia)镤
Chinese (Singapore)镤
Portuguese (Brazil)protactínio
Literary Chinese鏷
TagalogProtaktinyo
kbpPrɔtakɩtɩnɩyɔm
AfrikaansProtaktinium
Lingua Franca Novaprotactinio
Northern FrisianProtaktiinium
oloProtaktinii
Volapükprotaktinin
Sindhiپروٽيڪٽينيم
Mongolianпротактини
TajikПротактиний
Wu Chinese镤
SardinianProtoatìniu
SwahiliProtaktini
English (United Kingdom)protactinium
Moroccan Arabicپروطاكتينيوم
Egyptian Arabicبروتكتينيوم
Pashtoپروټېکټېنيوم
CornishProtaktiniom
BalineseProtaktinium

Protactinium on ChemicalAid

Australian Educational Vocabulary ID	scot/3563
CAB ID	7539
CAS Registry Number	7440-13-3
ChEBI ID	33386
ChemSpider ID	22387
DSSTOX compound identifier	DTXCID50147878
DSSTox substance ID	DTXSID50225387
Den Store Danske ID	protactinium
ECHA Substance Infocard ID	100.122.906
Elhuyar ZTH ID	030190
Encyclopedia of China ID (Second Edition)	224618
Encyclopædia Britannica Online ID	science/protactinium
Encyclopædia Universalis ID	protactinium
Freebase ID	/m/025s7xw
French Vikidia ID	Protactinium
GND ID	4175981-3
Gran Enciclopèdia Catalana ID	0135204
Great Russian Encyclopedia Online ID	3168919
InChI	InChI=1S/Pa
InChIKey	XLROVYAPLOFLNU-UHFFFAOYSA-N
KBpedia ID	Protactinium
Library of Congress authority ID	sh85107634
MeSH descriptor ID	D011478
NALT ID	3207
Namuwiki ID	프로트악티늄
National Library of Israel J9U ID	987007541390005171
OmegaWiki Defined Meaning	345414
OpenAlex ID	C505015426
PubChem CID	23945
Quora topic ID	Protactinium
Römpp online ID	RD-16-04500
Store norske leksikon ID	protactinium
Treccani ID	protoattinio
UNII	0S6855V29M
USGS Thesaurus ID	1547
WordNet 3.1 Synset ID	14675887-n

Protactinium (Pa)

Physical Properties

Chemical Properties

Other

Isotopes of Protactinium

211Pa

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

241Pa