Protactini

Protactini (Pa)

element with symbol Pa and atomic number of 91
Atomic Number91
Atomic Weight231.03588
Rhif màs231
Group
Period7
Blockf
Proton91 p+
Niwtron140 n0
Electron91 e-
Animated Bohr model of Pa (Protactini)

Nodwedd Ffisegol

Atomic Radius
180 pm
molar volume
covalent radius
169 pm
Metallic Radius
ionic radius
104 pm
Crystal Radius
118 pm
Van der Waals radius
243 pm
density
15.4 g/cm³
Atomic Radii Of The Elements: Protactini0102030405060708090100110120130140150160170180190200210220230240250pmAtomic RadiusCovalent RadiusMetallic RadiusVan der Waals radius

Nodwedd Gemegol

egni
proton affinity
electron affinity
ionization energy
ionization energy of Pa (Protactini)
enthalpy of vaporization
481.2 kJ/mol
enthalpy of fusion
16.7 kJ/mol
standard enthalpy of formation
563 kJ/mol
Electron
plisgyn yr electron2, 8, 18, 32, 20, 9, 2
Bohr model: Pa (Protactini)
valence electron2
Lewis structure: Pa (Protactini)
trefn yr electronnau[Rn] 5f2 6d1 7s2
1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 5f2 6d1 7s2
Enhanced Bohr model of Pa (Protactini)
Orbital Diagram of Pa (Protactini)
Cyflwr ocsidiad2, 3, 4, 5
Electronegatifedd
1.5
Electrophilicity Index
cyflwr sylfaenol mater
cyflwr materSolid
gaseous state of matter
Boiling Point
Melting Point
1,845.15 K
critical pressure
critical temperature
triple point
appearance
lliw
Silver
appearancebright, silvery metallic luster
Mynegrif plygiant
nodwedd ffisegol gwrthrych
Thermal Conductivity
thermal expansion
molar heat capacity
Specific Heat Capacity
heat capacity ratio
electrical properties
typeConductor
dargludedd trydanol
5.6 MS/m
Gwrthedd
0.00000018 m Ω
superconductivity
1.41 K
magnetism
typeparamagnetic
magnetic susceptibility (Mass)
0.0000000325 m³/Kg
magnetic susceptibility (Molar)
0.000000007509 m³/mol
magnetic susceptibility (Volume)
0.0004995
magnetic ordering
Curie temperature
Néel temperature
strwythur
Crystal StructureCentered Tetragonal (TET)
lattice constant
3.92 Å
Lattice Anglesπ/2, π/2, π/2
nodwedd mecanyddol deunyddiau
hardness
bulk modulus
shear modulus
Young's modulus
Poisson's ratio
speed of sound
classification
CategoryActinides, Actinides
CAS Group
IUPAC Group
Glawe Number35
Mendeleev Number18
Pettifor Number46
Geochemical ClassU/Th decay series
Goldschmidt classificationlitophile

other

Gas Basicity
polarizability
154 ± 20 a₀
C6 Dispersion Coefficient
allotrope
Neutron cross section
200
Neutron Mass Absorption
quantum number4K11/2
space group139 (I4/mmm)

Isotopes of Protactinium

Stable Isotopes0
Unstable Isotopes31
Natural Isotopes1

211Pa

Rhif màs211
neutron number120
relative atomic mass
211.023674036 ± 0.000074581 Da
g-factor
natural abundance
Dadfeilio ymbelydrol☢️ elfen ymbelydrol
Hanner oes
6 ± 3 ms
spin9/2
nuclear quadrupole moment
dyddiad darganfod2006
parity-

decay modeintensity
α (α emission)100%
β+ (β+ decay; β+ = ϵ + e+)
p (proton emission)

212Pa

Rhif màs212
neutron number121
relative atomic mass
212.023184819 ± 0.000094047 Da
g-factor
natural abundance
Dadfeilio ymbelydrol☢️ elfen ymbelydrol
Hanner oes
5.8 ± 1.9 ms
spin3
nuclear quadrupole moment
dyddiad darganfod1997
parity+

decay modeintensity
α (α emission)100%

213Pa

Rhif màs213
neutron number122
relative atomic mass
213.021099644 ± 0.000061374 Da
g-factor
natural abundance
Dadfeilio ymbelydrol☢️ elfen ymbelydrol
Hanner oes
7.4 ± 2.4 ms
spin9/2
nuclear quadrupole moment
dyddiad darganfod1995
parity-

decay modeintensity
α (α emission)100%

214Pa

Rhif màs214
neutron number123
relative atomic mass
214.020891055 ± 0.00008718 Da
g-factor
natural abundance
Dadfeilio ymbelydrol☢️ elfen ymbelydrol
Hanner oes
17 ± 3 ms
spin7
nuclear quadrupole moment
dyddiad darganfod1995
parity+

decay modeintensity
α (α emission)100%

215Pa

Rhif màs215
neutron number124
relative atomic mass
215.019113955 ± 0.000088513 Da
g-factor
natural abundance
Dadfeilio ymbelydrol☢️ elfen ymbelydrol
Hanner oes
14 ± 2 ms
spin9/2
nuclear quadrupole moment
dyddiad darganfod1979
parity-

decay modeintensity
α (α emission)100%

216Pa

Rhif màs216
neutron number125
relative atomic mass
216.019134633 ± 0.000026459 Da
g-factor
natural abundance
Dadfeilio ymbelydrol☢️ elfen ymbelydrol
Hanner oes
105 ± 12 ms
spin5
nuclear quadrupole moment
dyddiad darganfod1972
parity+

decay modeintensity
α (α emission)100%
β+ (β+ decay; β+ = ϵ + e+)

217Pa

Rhif màs217
neutron number126
relative atomic mass
217.018309024 ± 0.000013417 Da
g-factor
natural abundance
Dadfeilio ymbelydrol☢️ elfen ymbelydrol
Hanner oes
3.8 ± 0.2 ms
spin9/2
nuclear quadrupole moment
dyddiad darganfod1968
parity-

decay modeintensity
α (α emission)100%
β (β decay)

218Pa

Rhif màs218
neutron number127
relative atomic mass
218.020021133 ± 0.000019158 Da
g-factor
natural abundance
Dadfeilio ymbelydrol☢️ elfen ymbelydrol
Hanner oes
108 ± 5 us
spin8
nuclear quadrupole moment
dyddiad darganfod1979
parity-

decay modeintensity
α (α emission)100%

219Pa

Rhif màs219
neutron number128
relative atomic mass
219.019949909 ± 0.000074831 Da
g-factor
natural abundance
Dadfeilio ymbelydrol☢️ elfen ymbelydrol
Hanner oes
56 ± 9 ns
spin9/2
nuclear quadrupole moment
dyddiad darganfod2005
parity-

decay modeintensity
α (α emission)100%
β+ (β+ decay; β+ = ϵ + e+)

220Pa

Rhif màs220
neutron number129
relative atomic mass
220.021769753 ± 0.000015732 Da
g-factor
natural abundance
Dadfeilio ymbelydrol☢️ elfen ymbelydrol
Hanner oes
0.85 ± 0.06 us
spin1
nuclear quadrupole moment
dyddiad darganfod2005
parity-

decay modeintensity
α (α emission)100%
β+ (β+ decay; β+ = ϵ + e+)

221Pa

Rhif màs221
neutron number130
relative atomic mass
221.021873393 ± 0.000063746 Da
g-factor
natural abundance
Dadfeilio ymbelydrol☢️ elfen ymbelydrol
Hanner oes
5.9 ± 1.7 us
spin9/2
nuclear quadrupole moment
dyddiad darganfod1983
parity-

decay modeintensity
α (α emission)100%

222Pa

Rhif màs222
neutron number131
relative atomic mass
222.023687064 ± 0.000092975 Da
g-factor
natural abundance
Dadfeilio ymbelydrol☢️ elfen ymbelydrol
Hanner oes
3.8 ± 0.2 ms
spin1
nuclear quadrupole moment
dyddiad darganfod1970
parity-

decay modeintensity
α (α emission)100%

223Pa

Rhif màs223
neutron number132
relative atomic mass
223.023980414 ± 0.000081193 Da
g-factor
natural abundance
Dadfeilio ymbelydrol☢️ elfen ymbelydrol
Hanner oes
5.3 ± 0.3 ms
spin9/2
nuclear quadrupole moment
dyddiad darganfod1970
parity-

decay modeintensity
α (α emission)100%
β+ (β+ decay; β+ = ϵ + e+)

224Pa

Rhif màs224
neutron number133
relative atomic mass
224.025617286 ± 0.000008145 Da
g-factor
natural abundance
Dadfeilio ymbelydrol☢️ elfen ymbelydrol
Hanner oes
844 ± 19 ms
spin5
nuclear quadrupole moment
dyddiad darganfod1958
parity-

decay modeintensity
α (α emission)100%
β+ (β+ decay; β+ = ϵ + e+)

225Pa

Rhif màs225
neutron number134
relative atomic mass
225.026147927 ± 0.000087887 Da
g-factor
natural abundance
Dadfeilio ymbelydrol☢️ elfen ymbelydrol
Hanner oes
1.71 ± 0.1 s
spin5/2
nuclear quadrupole moment
dyddiad darganfod1958
parity-

decay modeintensity
α (α emission)100%

226Pa

Rhif màs226
neutron number135
relative atomic mass
226.027948217 ± 0.000012037 Da
g-factor
natural abundance
Dadfeilio ymbelydrol☢️ elfen ymbelydrol
Hanner oes
1.8 ± 0.2 m
spin1
nuclear quadrupole moment
dyddiad darganfod1949
parity-

decay modeintensity
α (α emission)74%
β+ (β+ decay; β+ = ϵ + e+)26%

227Pa

Rhif màs227
neutron number136
relative atomic mass
227.028803586 ± 0.000007797 Da
g-factor
natural abundance
Dadfeilio ymbelydrol☢️ elfen ymbelydrol
Hanner oes
38.3 ± 0.3 m
spin5/2
nuclear quadrupole moment
dyddiad darganfod1948
parity-

decay modeintensity
α (α emission)85%
ϵ (electron capture)15%

228Pa

Rhif màs228
neutron number137
relative atomic mass
228.031050758 ± 0.000004659 Da
g-factor
1.1666666666667 ± 0.16666666666667
natural abundance
Dadfeilio ymbelydrol☢️ elfen ymbelydrol
Hanner oes
22 ± 1 h
spin3
nuclear quadrupole moment
dyddiad darganfod1948
parity+

decay modeintensity
β+ (β+ decay; β+ = ϵ + e+)98.15%
α (α emission)1.85%

229Pa

Rhif màs229
neutron number138
relative atomic mass
229.032095585 ± 0.000003521 Da
g-factor
natural abundance
Dadfeilio ymbelydrol☢️ elfen ymbelydrol
Hanner oes
1.55 ± 0.04 d
spin5/2
nuclear quadrupole moment
dyddiad darganfod1949
parity+

decay modeintensity
ϵ (electron capture)99.51%
α (α emission)0.49%

230Pa

Rhif màs230
neutron number139
relative atomic mass
230.034539717 ± 0.000003261 Da
g-factor
1 ± 0.1
natural abundance
Dadfeilio ymbelydrol☢️ elfen ymbelydrol
Hanner oes
17.4 ± 0.5 d
spin2
nuclear quadrupole moment
dyddiad darganfod1948
parity-

decay modeintensity
β+ (β+ decay; β+ = ϵ + e+)92.2%
β (β decay)7.8%
α (α emission)0.0032%

231Pa

Rhif màs231
neutron number140
relative atomic mass
231.0358825 ± 0.000001901 Da
g-factor
1.3266666666667 ± 0.013333333333333
natural abundance
100
Dadfeilio ymbelydrol☢️ elfen ymbelydrol
Hanner oes
32.65 ± 0.2 ky
spin3/2
nuclear quadrupole moment
-1.72 ± 0.05
dyddiad darganfod1918
parity-

decay modeintensity
α (α emission)100%
SF (spontaneous fission)3%
24Ne (heavy cluster emission)13.4%
23F9.9%

232Pa

Rhif màs232
neutron number141
relative atomic mass
232.038590205 ± 0.000008206 Da
g-factor
natural abundance
Dadfeilio ymbelydrol☢️ elfen ymbelydrol
Hanner oes
1.32 ± 0.02 d
spin2
nuclear quadrupole moment
dyddiad darganfod1949
parity-

decay modeintensity
β (β decay)100%
ϵ (electron capture)

233Pa

Rhif màs233
neutron number142
relative atomic mass
233.040246535 ± 0.000001433 Da
g-factor
2.6666666666667 ± 0.46666666666667
natural abundance
Dadfeilio ymbelydrol☢️ elfen ymbelydrol
Hanner oes
26.975 ± 0.013 d
spin3/2
nuclear quadrupole moment
-3 ± 0.4
dyddiad darganfod1938
parity-

decay modeintensity
β (β decay)100%

234Pa

Rhif màs234
neutron number143
relative atomic mass
234.043305555 ± 0.000004395 Da
g-factor
natural abundance
Dadfeilio ymbelydrol☢️ elfen ymbelydrol
Hanner oes
6.7 ± 0.05 h
spin4
nuclear quadrupole moment
dyddiad darganfod1913
parity+

decay modeintensity
β (β decay)100%

235Pa

Rhif màs235
neutron number144
relative atomic mass
235.045399 ± 0.000015 Da
g-factor
natural abundance
Dadfeilio ymbelydrol☢️ elfen ymbelydrol
Hanner oes
24.4 ± 0.2 m
spin3/2
nuclear quadrupole moment
dyddiad darganfod1950
parity-

decay modeintensity
β (β decay)100%

236Pa

Rhif màs236
neutron number145
relative atomic mass
236.048668 ± 0.000015 Da
g-factor
natural abundance
Dadfeilio ymbelydrol☢️ elfen ymbelydrol
Hanner oes
9.1 ± 0.1 m
spin1
nuclear quadrupole moment
dyddiad darganfod1963
parity

decay modeintensity
β (β decay)100%
β SF (β-delayed fission)6%

237Pa

Rhif màs237
neutron number146
relative atomic mass
237.051023 ± 0.000014 Da
g-factor
natural abundance
Dadfeilio ymbelydrol☢️ elfen ymbelydrol
Hanner oes
8.7 ± 0.2 m
spin1/2
nuclear quadrupole moment
0
dyddiad darganfod1954
parity+

decay modeintensity
β (β decay)100%

238Pa

Rhif màs238
neutron number147
relative atomic mass
238.054637 ± 0.000017 Da
g-factor
natural abundance
Dadfeilio ymbelydrol☢️ elfen ymbelydrol
Hanner oes
2.28 ± 0.09 m
spin3
nuclear quadrupole moment
dyddiad darganfod1968
parity-

decay modeintensity
β (β decay)100%
β SF (β-delayed fission)2.6%

239Pa

Rhif màs239
neutron number148
relative atomic mass
239.05726 ± 0.00021 Da
g-factor
natural abundance
Dadfeilio ymbelydrol☢️ elfen ymbelydrol
Hanner oes
1.8 ± 0.5 h
spin1/2
nuclear quadrupole moment
0
dyddiad darganfod1995
parity+

decay modeintensity
β (β decay)100%

240Pa

Rhif màs240
neutron number149
relative atomic mass
240.061203 ± 0.000215 Da
g-factor
natural abundance
Dadfeilio ymbelydrol☢️ elfen ymbelydrol
Hanner oes
spin3
nuclear quadrupole moment
dyddiad darganfod
parity+

decay modeintensity
β (β decay)

241Pa

Rhif màs241
neutron number150
relative atomic mass
241.064134 ± 0.000322 Da
g-factor
natural abundance
Dadfeilio ymbelydrol☢️ elfen ymbelydrol
Hanner oes
spin1/2
nuclear quadrupole moment
0
dyddiad darganfod
parity+

decay modeintensity
β (β decay)
Protactinium-233

hanes

darganfyddwr neu ddyfeisiwrFredrich Soddy, John Cranston, Otto Hahn, Lise Meitner
man darganfodEngland/France
dyddiad darganfod1917
geirdarddiadGreek: proto and actinium (parent of actinium); it forms actinium when it radioactively decays.
ynganiadPRO-tak-tin-eh-em (Saesneg)

source

Abundance
Abundance in Earth's crust
0.0000014 mg/kg
natural abundance (cefnfor)
0.00000000005 mg/L
natural abundance (corff dynol)
0 %
natural abundance (Awyrfaen)
natural abundance (Haul)
Abundance in Universe
0 %

Nuclear Screening Constants