Plutonium

Plutonium (Pu)

Dense silvery radioactive metallic transuranic element, belongs to the actinoids. Pu-244 is the most stable isotope with a half-life of 7.6*10^7 years. Thirteen isotopes are known. Pu-239 is the most important, it undergoes nuclear fission with slow neutrons and is hence important to nuclear weapons and reactors. Plutonium production is monitored down to the gram to prevent military misuse. First produced by Gleen T. Seaborg, Edwin M. McMillan, J.W. Kennedy and A.C. Wahl in 1940.
Atomic Number94
Atomic Weight244
Mass Number221
Group
Period7
Blockf
Protons94 p+
Neutrons127 n0
Electrons94 e-
Plutonium ring.jpg Animated Bohr Model of Pu (Plutonium) Enhanced Bohr Model of Pu (Plutonium) Bohr Model: Pu (Plutonium) Orbital Diagram of Pu (Plutonium)

Properties

Atomic Radius
175 pm
Molar Volume
Covalent Radius
172 pm
Metallic Radius
Ionic Radius
100 pm
Crystal Radius
114 pm
Van der Waals Radius
243 pm
Density
19.7 g/cm³
Energy
Proton Affinity
Electron Affinity
Ionization Energy
Heat of Vaporization
343.5 kJ/mol
Heat of Fusion
2.8 kJ/mol
Heat of Formation
345 kJ/mol
Electrons
Electron Shells2, 8, 18, 32, 24, 8, 2
Valence Electrons6
Electron Configuration[Rn] 5f6 7s2
Oxidation States2, 3, 4, 5, 6, 7, 8
Electronegativity
1.3
Electrophilicity
Phases
PhaseSolid
Gas Phase
Boiling Point
3,501.15 K
Melting Point
913.15 K
Critical Pressure
Critical Temperature
Triple Point
Visual
Color
Silver
Appearancesilvery white, tarnishing to dark gray in air
Refractive Index
Thermodynamic Properties
Thermal Conductivity
Thermal Expansion
Molar Heat Capacity
Specific Heat Capacity
Heat Capacity Ratio (Adiabatic Index)
Electrical Properties
TypeConductor
Electrical Conductivity
0.67 MS/m
Electrical Resistivity
0.0000015 m Ω
Superconducting Point
Magnetism
Typeparamagnetic
Magnetic Susceptibility (Mass)
0.0000000317 m³/Kg
Magnetic Susceptibility (Molar)
0.000000007735 m³/mol
Magnetic Susceptibility (Volume)
0.0006282
Magnetic Ordering
Curie Point
Neel Point
Structure
Crystal StructureSimple Monoclinic (MCL)
Lattice Constant
Lattice Anglesπ/2, 1.776571, π/2
Mechanical Properties
Hardness
Bulk Modulus
Shear Modulus
43 GPa
Young Modulus
96 GPa
Poisson Ratio
0.21
Speed of Sound
2,260 m/s
Classification
CategoryActinides, Actinides
CAS Group
IUPAC Group
Glawe Number38
Mendeleev Number24
Pettifor Number43
Geochemical Class
Goldschmidt Classsynthetic
Other
Gas Basicity
Dipole Polarizability
132 ± 20 a₀
C6 Dispersion Coefficient
Allotropes
Neutron Cross Section
1.7
Neutron Mass Absorption
Quantum Numbers7F0
Space Group11 (P121/m1)

Isotopes of Plutonium

Stable Isotopes0
Unstable Isotopes27
Radioactive Isotopes27

221Pu

AbundanceRadioactive ☢️
Relative Atomic Mass
221.038572 ± 0.000322 Da
Mass Number221
G-Factor
Half Life
Spin9/2
Quadrupole Moment
Discovery Year
Parity+

221Pu Decay Modes
Decay ModeIntensity
α (α emission)%
SF (spontaneous fission)%

222Pu

AbundanceRadioactive ☢️
Relative Atomic Mass
222.037638 ± 0.000322 Da
Mass Number222
G-Factor
0
Half Life
Spin0
Quadrupole Moment
0
Discovery Year
Parity+

222Pu Decay Modes
Decay ModeIntensity
α (α emission)%
SF (spontaneous fission)%

223Pu

AbundanceRadioactive ☢️
Relative Atomic Mass
223.038777 ± 0.000322 Da
Mass Number223
G-Factor
Half Life
Spin9/2
Quadrupole Moment
Discovery Year
Parity+

223Pu Decay Modes
Decay ModeIntensity
α (α emission)%
SF (spontaneous fission)%

224Pu

AbundanceRadioactive ☢️
Relative Atomic Mass
224.037875 ± 0.000322 Da
Mass Number224
G-Factor
0
Half Life
Spin0
Quadrupole Moment
0
Discovery Year
Parity+

224Pu Decay Modes
Decay ModeIntensity
α (α emission)%
SF (spontaneous fission)%

225Pu

AbundanceRadioactive ☢️
Relative Atomic Mass
225.03897 ± 0.000322 Da
Mass Number225
G-Factor
Half Life
Spin7/2
Quadrupole Moment
Discovery Year
Parity+

225Pu Decay Modes
Decay ModeIntensity
α (α emission)%
SF (spontaneous fission)%

226Pu

AbundanceRadioactive ☢️
Relative Atomic Mass
226.03825 ± 0.000215 Da
Mass Number226
G-Factor
0
Half Life
Spin0
Quadrupole Moment
0
Discovery Year
Parity+

226Pu Decay Modes
Decay ModeIntensity
α (α emission)%
SF (spontaneous fission)%

227Pu

AbundanceRadioactive ☢️
Relative Atomic Mass
227.039474 ± 0.000107 Da
Mass Number227
G-Factor
Half Life
Spin5/2
Quadrupole Moment
Discovery Year
Parity+

227Pu Decay Modes
Decay ModeIntensity
α (α emission)%

228Pu

AbundanceRadioactive ☢️
Relative Atomic Mass
228.038763325 ± 0.000025069 Da
Mass Number228
G-Factor
0
Half Life
2.1 ± 1.3 s
Spin0
Quadrupole Moment
0
Discovery Year1994
Parity+

228Pu Decay Modes
Decay ModeIntensity
α (α emission)100%
β+ (β+ decay; β+ = ϵ + e+)%

229Pu

AbundanceRadioactive ☢️
Relative Atomic Mass
229.040145099 ± 0.000065092 Da
Mass Number229
G-Factor
Half Life
91 ± 26 s
Spin3/2
Quadrupole Moment
Discovery Year1994
Parity+

229Pu Decay Modes
Decay ModeIntensity
α (α emission)50%
β+ (β+ decay; β+ = ϵ + e+)50%
SF (spontaneous fission)7%

230Pu

AbundanceRadioactive ☢️
Relative Atomic Mass
230.039648313 ± 0.000015514 Da
Mass Number230
G-Factor
0
Half Life
105 ± 10 s
Spin0
Quadrupole Moment
0
Discovery Year1990
Parity+

230Pu Decay Modes
Decay ModeIntensity
α (α emission)100%
β+ (β+ decay; β+ = ϵ + e+)%

231Pu

AbundanceRadioactive ☢️
Relative Atomic Mass
231.041125946 ± 0.000023683 Da
Mass Number231
G-Factor
Half Life
8.6 ± 0.5 m
Spin3/2
Quadrupole Moment
Discovery Year1999
Parity+

231Pu Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)%
α (α emission)13%

232Pu

AbundanceRadioactive ☢️
Relative Atomic Mass
232.041182133 ± 0.000018126 Da
Mass Number232
G-Factor
0
Half Life
33.7 ± 0.5 m
Spin0
Quadrupole Moment
0
Discovery Year1973
Parity+

232Pu Decay Modes
Decay ModeIntensity
ϵ (electron capture)%
α (α emission)20%

233Pu

AbundanceRadioactive ☢️
Relative Atomic Mass
233.042997411 ± 0.000058162 Da
Mass Number233
G-Factor
Half Life
20.9 ± 0.4 m
Spin5/2
Quadrupole Moment
Discovery Year1957
Parity+

233Pu Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%
α (α emission)0.12%

234Pu

AbundanceRadioactive ☢️
Relative Atomic Mass
234.043317489 ± 0.000007298 Da
Mass Number234
G-Factor
0
Half Life
8.8 ± 0.1 h
Spin0
Quadrupole Moment
0
Discovery Year1949
Parity+

234Pu Decay Modes
Decay ModeIntensity
ϵ (electron capture)94%
α (α emission)6%

235Pu

AbundanceRadioactive ☢️
Relative Atomic Mass
235.045284609 ± 0.00002203 Da
Mass Number235
G-Factor
Half Life
25.3 ± 0.5 m
Spin5/2
Quadrupole Moment
Discovery Year1957
Parity+

235Pu Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)99.9972%
α (α emission)0.0028%

236Pu

AbundanceRadioactive ☢️
Relative Atomic Mass
236.046056661 ± 0.000001942 Da
Mass Number236
G-Factor
0
Half Life
2.858 ± 0.008 y
Spin0
Quadrupole Moment
0
Discovery Year1949
Parity+

236Pu Decay Modes
Decay ModeIntensity
α (α emission)100%
SF (spontaneous fission)1.9%
28Mg2%
+ (double β+ decay)%

237Pu

AbundanceRadioactive ☢️
Relative Atomic Mass
237.048407888 ± 0.000001821 Da
Mass Number237
G-Factor
Half Life
45.64 ± 0.04 d
Spin7/2
Quadrupole Moment
Discovery Year1949
Parity-

237Pu Decay Modes
Decay ModeIntensity
ϵ (electron capture)99.9958%
α (α emission)0.0042%

238Pu

AbundanceRadioactive ☢️
Relative Atomic Mass
238.049558175 ± 0.000001221 Da
Mass Number238
G-Factor
0
Half Life
87.7 ± 0.1 y
Spin0
Quadrupole Moment
0
Discovery Year1949
Parity+

238Pu Decay Modes
Decay ModeIntensity
α (α emission)100%
SF (spontaneous fission)1.9%
32Si1.4%
30Mg6%

239Pu

AbundanceRadioactive ☢️
Relative Atomic Mass
239.052161596 ± 0.000001194 Da
Mass Number239
G-Factor
0.404 ± 0.008
Half Life
24.11 ± 0.03 ky
Spin1/2
Quadrupole Moment
0
Discovery Year1946
Parity+

239Pu Decay Modes
Decay ModeIntensity
α (α emission)100%
SF (spontaneous fission)3.1%

240Pu

AbundanceRadioactive ☢️
Relative Atomic Mass
240.05381174 ± 0.000001186 Da
Mass Number240
G-Factor
0
Half Life
6.561 ± 0.007 ky
Spin0
Quadrupole Moment
0
Discovery Year1949
Parity+

240Pu Decay Modes
Decay ModeIntensity
α (α emission)100%
SF (spontaneous fission)5.796%
34Si1.3%

241Pu

AbundanceRadioactive ☢️
Relative Atomic Mass
241.056849651 ± 0.000001186 Da
Mass Number241
G-Factor
-0.2712 ± 0.0056
Half Life
14.329 ± 0.029 y
Spin5/2
Quadrupole Moment
6
Discovery Year1949
Parity+

241Pu Decay Modes
Decay ModeIntensity
β (β decay)100%
α (α emission)0.00245%
SF (spontaneous fission)2.4%

242Pu

AbundanceRadioactive ☢️
Relative Atomic Mass
242.058740979 ± 0.000001336 Da
Mass Number242
G-Factor
0
Half Life
375 ± 2 ky
Spin0
Quadrupole Moment
0
Discovery Year1950
Parity+

242Pu Decay Modes
Decay ModeIntensity
α (α emission)100%
SF (spontaneous fission)5.51%

243Pu

AbundanceRadioactive ☢️
Relative Atomic Mass
243.062002068 ± 0.000002728 Da
Mass Number243
G-Factor
Half Life
4.9553 ± 0.0025 h
Spin7/2
Quadrupole Moment
Discovery Year1951
Parity+

243Pu Decay Modes
Decay ModeIntensity
β (β decay)100%

244Pu

AbundanceRadioactive ☢️
Relative Atomic Mass
244.064204401 ± 0.000002518 Da
Mass Number244
G-Factor
0
Half Life
81.3 ± 0.3 My
Spin0
Quadrupole Moment
0
Discovery Year1954
Parity+

244Pu Decay Modes
Decay ModeIntensity
α (α emission)99.877%
SF (spontaneous fission)0.123%
(double β decay)7.3%

245Pu

AbundanceRadioactive ☢️
Relative Atomic Mass
245.067824554 ± 0.000014621 Da
Mass Number245
G-Factor
Half Life
10.5 ± 0.1 h
Spin9/2
Quadrupole Moment
Discovery Year1955
Parity-

245Pu Decay Modes
Decay ModeIntensity
β (β decay)100%

246Pu

AbundanceRadioactive ☢️
Relative Atomic Mass
246.070204172 ± 0.000016087 Da
Mass Number246
G-Factor
0
Half Life
10.84 ± 0.02 d
Spin0
Quadrupole Moment
0
Discovery Year1955
Parity+

246Pu Decay Modes
Decay ModeIntensity
β (β decay)100%

247Pu

AbundanceRadioactive ☢️
Relative Atomic Mass
247.0743 ± 0.000215 Da
Mass Number247
G-Factor
Half Life
2.27 ± 0.23 d
Spin1/2
Quadrupole Moment
0
Discovery Year1983
Parity+

247Pu Decay Modes
Decay ModeIntensity
β (β decay)100%

History

Plutonium was first produced in 1940 by Glenn T. Seaborg, Edwin M. McMillan, Joseph W. Kennedy and Arthur Wahl. Plutonium-238 was produced by deuteron bombardment of uranium-238 in the 60-inch cyclotron at the University of California, Berkeley. The Berkeley team made neptunium-238 which decayed to plutonium-238. Named after the planet Pluto

DiscoverersG.T.Seaborg, J.W.Kennedy, E.M.McMillan, A.C.Wohl
Discovery LocationUnited States
Discovery Year1940
Etymology (Name Origin)Named for the planet Pluto.
Pronunciationploo-TOE-ni-em (English)
Plutonium is harmful due to its radioactivity
The atomic bomb dropped on Nagasaki, Japan in 1945 had a plutonium core

Uses

The isotope plutonium-239 is a key fissile component in nuclear weapons, due to its ease of fission and availability. Plutonium-238 has also been used successfully to power artificial heart pacemakers, to reduce the risk of repeated surgery. Plutonium-238 mixed with beryllium is used to generate neutrons for research purposes. Used in bombs and reactors. Small quantities are used in thermo-electric generators.

Sources

Found rarely in some uranium ores. Made by bombarding uranium with neutrons.

Abundance
Abundance in Earth's crust
Abundance in Oceans
Abundance in Human Body
0 %
Abundance in Meteor
0 %
Abundance in Sun
0 %
Abundance in Universe
0 %

Nuclear Screening Constants