Actinium

Actinium (Ac)

chemical element with the atomic number of 89
Atomic Number89
Atomic Weight227
mass number205
Group3
Period7
Blockd
proton89 p+
neutron116 n0
electron89 e-
Animated Bohr model of Ac (Actinium)

Āhuatanga Ōkiko

Atomic Radius
195 pm
molar volume
22.54 cm³/mol
covalent radius
186 pm
Metallic Radius
ionic radius
112 pm
Crystal Radius
126 pm
Van der Waals radius
247 pm
density
Atomic Radii Of The Elements: Actinium0102030405060708090100110120130140150160170180190200210220230240250pmAtomic RadiusCovalent RadiusMetallic RadiusVan der Waals radius

Chemical Property

energy
proton affinity
electron affinity
ionization energy
5.380226 eV/particle
ionization energy of Ac (Actinium)
enthalpy of vaporization
292.9 kJ/mol
enthalpy of fusion
10.5 kJ/mol
standard enthalpy of formation
406 kJ/mol
electron
electron shell2, 8, 18, 32, 18, 9, 2
Bohr model: Ac (Actinium)
valence electron2
Lewis structure: Ac (Actinium)
electron configuration[Rn] 6d1 7s2
1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 6d1 7s2
Enhanced Bohr model of Ac (Actinium)
Orbital Diagram of Ac (Actinium)
oxidation number2, 3
electronegativity
1.1
Electrophilicity Index
0.8159546412794374 eV/particle
fundamental state of matter
phase of matterSolid
gaseous state of matter
Boiling Point
3,473.15 K
Melting Point
1,323.15 K
critical pressure
critical temperature
triple point
appearance
color
Silver
appearance
refractive index
thermodynamic material property
Thermal Conductivity
thermal expansion
molar heat capacity
Specific Heat Capacity
heat capacity ratio
electrical properties
type
electrical conductivity
electrical resistivity
superconductivity
magnetism
type
magnetic susceptibility (Mass)
magnetic susceptibility (Molar)
magnetic susceptibility (Volume)
magnetic ordering
Curie temperature
Néel temperature
structure
Crystal StructureFace Centered Cubic (FCC)
lattice constant
5.31 Å
Lattice Anglesπ/2, π/2, π/2
mechanical property
hardness
bulk modulus
shear modulus
Young's modulus
Poisson's ratio
speed of sound
classification
CategoryActinides, Actinides
CAS GroupIIIA
IUPAC GroupIIIB
Glawe Number33
Mendeleev Number14
Pettifor Number48
Geochemical ClassU/Th decay series
Goldschmidt classificationsynthetic

other

Gas Basicity
polarizability
203 ± 12 a₀
C6 Dispersion Coefficient
allotrope
Neutron cross section
880
Neutron Mass Absorption
0.078
quantum number2D3/2
space group225 (Fm_3m)

Isotopes of Actinium

Stable Isotopes0
Unstable Isotopes33
Natural Isotopes0

205Ac

mass number205
neutron number116
relative atomic mass
205.015144152 ± 0.000063682 Da
g-factor
natural abundance
radioactivity☢️ radioactive element
half-life
80 ± 60 ms
spin9/2
nuclear quadrupole moment
time of discovery or invention2014
parity-

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

206Ac

mass number206
neutron number117
relative atomic mass
206.014476477 ± 0.000069874 Da
g-factor
natural abundance
radioactivity☢️ radioactive element
half-life
25 ± 7 ms
spin3
nuclear quadrupole moment
time of discovery or invention1998
parity+

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

207Ac

mass number207
neutron number118
relative atomic mass
207.011965967 ± 0.000060384 Da
g-factor
natural abundance
radioactivity☢️ radioactive element
half-life
31 ± 8 ms
spin9/2
nuclear quadrupole moment
time of discovery or invention1994
parity-

decay modeintensity
α (α emission)100%

208Ac

mass number208
neutron number119
relative atomic mass
208.011552251 ± 0.000069225 Da
g-factor
natural abundance
radioactivity☢️ radioactive element
half-life
97 ± 15 ms
spin3
nuclear quadrupole moment
time of discovery or invention1994
parity+

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

209Ac

mass number209
neutron number120
relative atomic mass
209.009495375 ± 0.000059953 Da
g-factor
natural abundance
radioactivity☢️ radioactive element
half-life
94 ± 10 ms
spin9/2
nuclear quadrupole moment
time of discovery or invention1968
parity-

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

210Ac

mass number210
neutron number121
relative atomic mass
210.009408625 ± 0.000066782 Da
g-factor
natural abundance
radioactivity☢️ radioactive element
half-life
350 ± 40 ms
spin7
nuclear quadrupole moment
time of discovery or invention1968
parity+

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

211Ac

mass number211
neutron number122
relative atomic mass
211.007668846 ± 0.000057706 Da
g-factor
natural abundance
radioactivity☢️ radioactive element
half-life
213 ± 25 ms
spin9/2
nuclear quadrupole moment
time of discovery or invention1968
parity-

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

212Ac

mass number212
neutron number123
relative atomic mass
212.007836442 ± 0.000023492 Da
g-factor
natural abundance
radioactivity☢️ radioactive element
half-life
895 ± 28 ms
spin7
nuclear quadrupole moment
time of discovery or invention1968
parity+

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

213Ac

mass number213
neutron number124
relative atomic mass
213.006592665 ± 0.000012522 Da
g-factor
natural abundance
radioactivity☢️ radioactive element
half-life
738 ± 16 ms
spin9/2
nuclear quadrupole moment
time of discovery or invention1968
parity-

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

214Ac

mass number214
neutron number125
relative atomic mass
214.0069064 ± 0.000014547 Da
g-factor
natural abundance
radioactivity☢️ radioactive element
half-life
8.2 ± 0.2 s
spin5
nuclear quadrupole moment
time of discovery or invention1968
parity+

decay modeintensity
α (α emission)93%
β+ (β+ decay; β+ = ϵ + e+)7%

215Ac

mass number215
neutron number126
relative atomic mass
215.006474061 ± 0.000013318 Da
g-factor
natural abundance
radioactivity☢️ radioactive element
half-life
171 ± 10 ms
spin9/2
nuclear quadrupole moment
time of discovery or invention1968
parity-

decay modeintensity
α (α emission)100%
β+ (β+ decay; β+ = ϵ + e+)0.09%

216Ac

mass number216
neutron number127
relative atomic mass
216.008749101 ± 0.000009908 Da
g-factor
natural abundance
radioactivity☢️ radioactive element
half-life
440 ± 16 us
spin1
nuclear quadrupole moment
time of discovery or invention1967
parity-

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

217Ac

mass number217
neutron number128
relative atomic mass
217.009342325 ± 0.000012048 Da
g-factor
0.85111111111111 ± 0.011111111111111
natural abundance
radioactivity☢️ radioactive element
half-life
69 ± 4 ns
spin9/2
nuclear quadrupole moment
time of discovery or invention1972
parity-

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

218Ac

mass number218
neutron number129
relative atomic mass
218.01164886 ± 0.000061853 Da
g-factor
natural abundance
radioactivity☢️ radioactive element
half-life
1 ± 0.04 us
spin1
nuclear quadrupole moment
time of discovery or invention1970
parity-

decay modeintensity
α (α emission)100%

219Ac

mass number219
neutron number130
relative atomic mass
219.012420425 ± 0.000055263 Da
g-factor
natural abundance
radioactivity☢️ radioactive element
half-life
9.4 ± 1 us
spin9/2
nuclear quadrupole moment
time of discovery or invention1970
parity-

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

220Ac

mass number220
neutron number131
relative atomic mass
220.014754527 ± 0.000006579 Da
g-factor
natural abundance
radioactivity☢️ radioactive element
half-life
26.36 ± 0.19 ms
spin3
nuclear quadrupole moment
time of discovery or invention1970
parity-

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

221Ac

mass number221
neutron number132
relative atomic mass
221.015599721 ± 0.000061086 Da
g-factor
natural abundance
radioactivity☢️ radioactive element
half-life
52 ± 2 ms
spin9/2
nuclear quadrupole moment
time of discovery or invention1968
parity-

decay modeintensity
α (α emission)100%

222Ac

mass number222
neutron number133
relative atomic mass
222.017844232 ± 0.000005044 Da
g-factor
natural abundance
radioactivity☢️ radioactive element
half-life
5 ± 0.5 s
spin1
nuclear quadrupole moment
time of discovery or invention1949
parity-

decay modeintensity
α (α emission)99%
β+ (β+ decay; β+ = ϵ + e+)1%

223Ac

mass number223
neutron number134
relative atomic mass
223.019135982 ± 0.000007457 Da
g-factor
natural abundance
radioactivity☢️ radioactive element
half-life
2.1 ± 0.05 m
spin5/2
nuclear quadrupole moment
time of discovery or invention1948
parity-

decay modeintensity
α (α emission)99%
ϵ (electron capture)

224Ac

mass number224
neutron number135
relative atomic mass
224.021722249 ± 0.000004389 Da
g-factor
0
natural abundance
radioactivity☢️ radioactive element
half-life
2.78 ± 0.16 h
spin0
nuclear quadrupole moment
0
time of discovery or invention1948
parity-

decay modeintensity
β+ (β+ decay; β+ = ϵ + e+)90.5%
α (α emission)9.5%
β (β decay)

225Ac

mass number225
neutron number136
relative atomic mass
225.023228601 ± 0.000005107 Da
g-factor
natural abundance
radioactivity☢️ radioactive element
half-life
9.919 ± 0.0021 d
spin3/2
nuclear quadrupole moment
time of discovery or invention1947
parity-

decay modeintensity
α (α emission)100%
14C5.3%

226Ac

mass number226
neutron number137
relative atomic mass
226.026096999 ± 0.000003327 Da
g-factor
natural abundance
radioactivity☢️ radioactive element
half-life
29.37 ± 0.12 h
spin1
nuclear quadrupole moment
time of discovery or invention1950
parity-

decay modeintensity
β (β decay)83%
ϵ (electron capture)17%
α (α emission)0.006%

227Ac

mass number227
neutron number138
relative atomic mass
227.027750594 ± 0.000002068 Da
g-factor
natural abundance
radioactivity☢️ radioactive element
half-life
21.772 ± 0.003 y
spin3/2
nuclear quadrupole moment
time of discovery or invention1851
parity-

decay modeintensity
β (β decay)98.62%
α (α emission)1.38%

228Ac

mass number228
neutron number139
relative atomic mass
228.031019685 ± 0.000002247 Da
g-factor
natural abundance
radioactivity☢️ radioactive element
half-life
6.15 ± 0.02 h
spin3
nuclear quadrupole moment
time of discovery or invention1908
parity+

decay modeintensity
β (β decay)100%

229Ac

mass number229
neutron number140
relative atomic mass
229.032947 ± 0.000013 Da
g-factor
natural abundance
radioactivity☢️ radioactive element
half-life
62.7 ± 0.5 m
spin3/2
nuclear quadrupole moment
time of discovery or invention1952
parity+

decay modeintensity
β (β decay)100%

230Ac

mass number230
neutron number141
relative atomic mass
230.036327 ± 0.000017 Da
g-factor
natural abundance
radioactivity☢️ radioactive element
half-life
122 ± 3 s
spin1
nuclear quadrupole moment
time of discovery or invention1973
parity+

decay modeintensity
β (β decay)100%
β SF (β-delayed fission)1.2%

231Ac

mass number231
neutron number142
relative atomic mass
231.038393 ± 0.000014 Da
g-factor
natural abundance
radioactivity☢️ radioactive element
half-life
7.5 ± 0.1 m
spin1/2
nuclear quadrupole moment
0
time of discovery or invention1973
parity+

decay modeintensity
β (β decay)100%

232Ac

mass number232
neutron number143
relative atomic mass
232.042034 ± 0.000014 Da
g-factor
natural abundance
radioactivity☢️ radioactive element
half-life
1.98 ± 0.08 m
spin1
nuclear quadrupole moment
time of discovery or invention1986
parity+

decay modeintensity
β (β decay)100%

233Ac

mass number233
neutron number144
relative atomic mass
233.044346 ± 0.000014 Da
g-factor
natural abundance
radioactivity☢️ radioactive element
half-life
143 ± 10 s
spin1/2
nuclear quadrupole moment
0
time of discovery or invention1983
parity+

decay modeintensity
β (β decay)100%

234Ac

mass number234
neutron number145
relative atomic mass
234.048139 ± 0.000015 Da
g-factor
natural abundance
radioactivity☢️ radioactive element
half-life
45 ± 2 s
spin1
nuclear quadrupole moment
time of discovery or invention1986
parity+

decay modeintensity
β (β decay)100%

235Ac

mass number235
neutron number146
relative atomic mass
235.05084 ± 0.000015 Da
g-factor
natural abundance
radioactivity☢️ radioactive element
half-life
62 ± 4 s
spin1/2
nuclear quadrupole moment
0
time of discovery or invention2006
parity+

decay modeintensity
β (β decay)100%

236Ac

mass number236
neutron number147
relative atomic mass
236.054988 ± 0.000041 Da
g-factor
natural abundance
radioactivity☢️ radioactive element
half-life
4.5 ± 3.6 m
spin3
nuclear quadrupole moment
time of discovery or invention2010
parity+

decay modeintensity
β (β decay)100%

237Ac

mass number237
neutron number148
relative atomic mass
237.057993 ± 0.000429 Da
g-factor
natural abundance
radioactivity☢️ radioactive element
half-life
spin1/2
nuclear quadrupole moment
0
time of discovery or invention
parity+

decay modeintensity
β (β decay)
Actinium sample (31481701837)
Electron shell 089 Actinium

kōrero nehe

discoverer or inventorAndré Debierne
location of discoveryFrance
time of discovery or invention1899
etymologyGreek: akis, aktinos (ray).
pronunciationak-TIN-i-em (Ingarihi)

source

Abundance
Abundance in Earth's crust
0.00000000055 mg/kg
natural abundance (Moana nui)
natural abundance (human body)
0 %
natural abundance (meteoroid)
natural abundance (Te Rā)
0 %
Abundance in Universe
0 %

Nuclear Screening Constants