"Pu" redirects here. For the abbreviation, see PU. For Chinese and other personal and place names starting with "Pu", see Special:Prefixindex/Pu.

94 neptunium ← plutonium → americium Sm ↑ Pu ↓ (Uqq) Periodic Table - Extended Periodic Table
General
Name, Symbol, Number	plutonium, Pu, 94
Chemical series	actinides
Group, Period, Block	n/a, 7, f
Appearance	silvery white
Standard atomic weight	(244) g·mol−1
Electron configuration	[Rn] 5f6 7s2
Electrons per shell	2, 8, 18, 32, 24, 8, 2
Physical properties
Phase	solid
Density (near r.t.)	19.816 g·cm−3
Liquid density at m.p.	16.63 g·cm−3
Melting point	912.5 K (639.4 °C, 1182.9 °F)
Boiling point	3505 K (3228 °C, 5842 °F)
Heat of fusion	2.82 kJ·mol−1
Heat of vaporization	333.5 kJ·mol−1
Heat capacity	(25 °C) 35.5 J·mol−1·K−1
Vapor pressure P(Pa) 1 10 100 1 k 10 k 100 k at T(K) 1756 1953 2198 2511 2926 3499
Atomic properties
Crystal structure	monoclinic
Oxidation states	6, 5, 4, 3 (amphoteric oxide)
Electronegativity	1.28 (Pauling scale)
Ionization energies	1st: 584.7 kJ/mol
Atomic radius	175 pm
Miscellaneous
Magnetic ordering	no data
Electrical resistivity	(0 °C) 1.460 µΩ·m
Thermal conductivity	(300 K) 6.74 W·m−1·K−1
Thermal expansion	(25 °C) 46.7 µm·m−1·K−1
Speed of sound (thin rod)	(20 °C) 2260 m/s
Young's modulus	96 GPa
Shear modulus	43 GPa
Poisson ratio	0.21
CAS registry number	7440-07-5
Selected isotopes
Main article: Isotopes of plutonium iso NA half-life DM DE (MeV) DP 238Pu syn 88 y SF - - α 5.5 234U 239Pu syn 2.41×104 y SF - - α 5.245 235U 240Pu syn 6.5×103 y SF - - α 5.256 236U 241Pu syn 14 y β− .02078 241Am SF - - 242Pu syn 3.73×105 y SF - - α 4.984 238U 244Pu trace 8.08×107 y α 4.666 240U SF - -
References

Plutonium (pronounced /pluːˈtoʊniəm/) is a rare radioactive, metallic and toxic chemical element. It has the symbol Pu and the atomic number 94. It is a fissile element used in most modern nuclear weapons. The most significant isotope of plutonium is ²³⁹Pu, with a half-life of 24,100 years. It can be made from natural uranium. The most stable isotope is ²⁴⁴Pu, with a half-life of about 80 million years, long enough to be found in extremely small quantities in nature, making ²⁴⁴Pu the nucleon-richest atom that naturally occurs in the Earth's crust, albeit in small traces.^[1] Plutonium can mean:- Plutonium is a radioactive chemical element. ... General Name, Symbol, Number Plutonium, Pu, 94 Chemical series Actinides Period, Block 7 , f Density, Hardness 19816 kg/m3, no data Appearance silvery white metal Atomic properties Atomic weight 244. ... General Name, Symbol, Number neptunium, Np, 93 Chemical series actinides Group, Period, Block n/a, 7, f Appearance silvery metallic Standard atomic weight (237) g·mol−1 Electron configuration [Rn] 5f4 6d1 7s2 Electrons per shell 2, 8, 18, 32, 22, 9, 2 Physical properties Phase solid Density (near r. ... General Name, Symbol, Number americium, Am, 95 Chemical series actinides Group, Period, Block n/a, 7, f Appearance silvery white sometimes yellow Standard atomic weight (243) g·mol−1 Electron configuration [Rn] 5f7 7s2 Electrons per shell 2, 8, 18, 32, 25, 8, 2 Physical properties Phase solid Density (near... General Name, Symbol, Number samarium, Sm, 62 Chemical series lanthanides Group, Period, Block n/a, 6, f Appearance silvery white Atomic mass 150. ... Image File history File links Download high resolution version (890x260, 0 KB)stub for unified link coding, copy of File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... This is a standard display of the periodic table of the elements. ... An extended periodic table was suggested by Glenn T. Seaborg in 1969. ... This is a list of chemical elements, sorted by name and color coded according to type of element. ... A table of chemical elements ordered by atomic number and color coded according to type of element. ... A group, also known as a family, is a vertical column in the periodic table of the chemical elements. ... The actinide (or actinoid) series encompasses the 15 chemical elements that lie between actinium and lawrencium on the periodic table, with atomic numbers 89 - 103[1]. The actinide series derives its name from the first element in the series, actinium. ... A group, also known as a family, is a vertical column in the periodic table of the chemical elements. ... In the periodic table of the elements, a period is a horizontal row of the table. ... A block of the periodic table of elements is a set of adjacent groups. ... 6 *Lanthanides 7 **Actinides IUPAC has not recommended a specific format for the periodic table, so different conventions are permitted and are often used for the group number of lanthanides and actinides. ... A period 7 element is one of the chemical elements in the seventh row (or period) of the periodic table of the elements. ... The f-block of the periodic table of elements consists of those elements for which, in the atomic ground state, the highest-energy electrons occupy f-orbitals. ... Color is an important part of the visual arts. ... Image File history File links Pu,94. ... The atomic mass (ma) is the mass of an atom at rest, most often expressed in unified atomic mass units. ... To help compare different orders of magnitude we list here masses between 60. ... Electron atomic and molecular orbitals In atomic physics and quantum chemistry, the electron configuration is the arrangement of electrons in an atom, molecule, or other physical structure (, a crystal). ... For other uses, see Radon (disambiguation). ... For other uses, see Electron (disambiguation). ... Example of a sodium electron shell model An electron shell, also known as a main energy level, is a group of atomic orbitals with the same value of the principal quantum number n. ... In the physical sciences, a phase is a set of states of a macroscopic physical system that have relatively uniform chemical composition and physical properties (i. ... This box:      For other uses, see Solid (disambiguation). ... For other uses, see Density (disambiguation). ... For other uses, see Room temperature (disambiguation). ... For other uses, see Density (disambiguation). ... The melting point of a solid is the temperature range at which it changes state from solid to liquid. ... The melting point of a solid is the temperature range at which it changes state from solid to liquid. ... For other uses, see Kelvin (disambiguation). ... For other uses, see Celsius (disambiguation). ... For other uses, see Fahrenheit (disambiguation). ... Italic text This article is about the boiling point of liquids. ... For other uses, see Kelvin (disambiguation). ... For other uses, see Celsius (disambiguation). ... For other uses, see Fahrenheit (disambiguation). ... Standard enthalpy change of fusion of period three. ... The joule per mole (symbol: J·mol-1) is an SI derived unit of energy per amount of material. ... The standard enthalpy change of vaporization, ΔvHo, also (less correctly) known as the heat of vaporization is the energy required to transform a given quantity of a substance into a gas. ... The joule per mole (symbol: J·mol-1) is an SI derived unit of energy per amount of material. ... To meet Wikipedias quality standards, this article or section may require cleanup. ... Vapor pressure is the pressure of a vapor in equilibrium with its non-vapor phases. ... Enargite crystals In mineralogy and crystallography, a crystal structure is a unique arrangement of atoms in a crystal. ... In chemistry, the oxidation state is an indicator of the degree of oxidation of an atom in a chemical compound. ... In chemistry, an amphoteric substance is one that can react with either an acid or base (more generally, the word describes something made of, or acting like, two components). ... Electronegativity is a measure of the ability of an atom or molecule to attract electrons in the context of a chemical bond. ... The ionization energy (IE) of an atom or of a molecule is the energy required to strip it of an electron. ... Kilojoule per mole are an SI derived unit of energy per amount of material, where energy is measured in units of 1000 joules, and the amount of material is measured in mole units. ... Atomic radius: Ionic radius Covalent radius Metallic radius van der Waals radius edit Atomic radius, and more generally the size of an atom, is not a precisely defined physical quantity, nor is it constant in all circumstances. ... You have big harry skanky balls ... One picometre is defined as 1x10-12 metres, in standard units. ... For other senses of this word, see magnetism (disambiguation). ... Electrical resistivity (also known as specific electrical resistance) is a measure of how strongly a material opposes the flow of electric current. ... K value redirects here. ... During heat transfer, the energy that is stored in the intermolecular bonds between atoms changes. ... For other uses, see Speed of sound (disambiguation). ... Metre per second (U.S. spelling: meter per second) is an SI derived unit of both speed (scalar) and velocity (vector), defined by distance in metres divided by time in seconds. ... In solid mechanics, Youngs modulus (E) is a measure of the stiffness of a given material. ... Shear strain In materials science, shear modulus or modulus of rigidity, denoted by G, or sometimes S or μ, is defined as the ratio of shear stress to the shear strain:[1] where = shear stress; is the force which acts is the area on which the force acts = shear strain; is... Figure 1: Rectangular specimen subject to compression, with Poissons ratio circa 0. ... CAS registry numbers are unique numerical identifiers for chemical compounds, polymers, biological sequences, mixtures and alloys. ... Plutonium (Pu) Has no stable isotopes. ... For other uses, see Isotope (disambiguation). ... Natural abundance refers to the prevalence of different isotopes of an element as found in nature. ... Half-Life For a quantity subject to exponential decay, the half-life is the time required for the quantity to fall to half of its initial value. ... In physics, the decay mode describes a particular way a particle decays. ... The decay energy is the energy released by a nuclear decay. ... The electronvolt (symbol eV) is a unit of energy. ... In nuclear physics, a decay product, also known as a daughter product, is a nuclide resulting from the radioactive decay of a parent or precursor nuclide. ... A Synthetic radioisotope is a radionuclide that is not found in nature: no natural process or mechanism exists which produces it, or it is so unstable that it decays away in a very short period of time. ... To help compare orders of magnitude of different times this page lists times between 109 seconds (a gigasecond) and 1010 seconds (32 years and 320 years). ... Spontaneous fission (SF) is a form of radioactive decay characteristic of very heavy isotopes, and is theoretically possible for any atomic nucleus whose mass is greater than or equal to 100 amu (elements near ruthenium). ... Alpha decay is a form of radioactive decay in which an atomic nucleus ejects an alpha particle and transforms into a nucleus with mass number 4 less and atomic number 2 less. ... This article is about the chemical element. ... A Synthetic radioisotope is a radionuclide that is not found in nature: no natural process or mechanism exists which produces it, or it is so unstable that it decays away in a very short period of time. ... To help compare orders of magnitude of different times this page lists times between 32 000 years and 320 000 years (1012 seconds—a terasecond—and 1013 seconds). ... Spontaneous fission (SF) is a form of radioactive decay characteristic of very heavy isotopes, and is theoretically possible for any atomic nucleus whose mass is greater than or equal to 100 amu (elements near ruthenium). ... Alpha decay is a form of radioactive decay in which an atomic nucleus ejects an alpha particle and transforms into a nucleus with mass number 4 less and atomic number 2 less. ... This article is about the chemical element. ... A Synthetic radioisotope is a radionuclide that is not found in nature: no natural process or mechanism exists which produces it, or it is so unstable that it decays away in a very short period of time. ... To help compare orders of magnitude of different times this page lists times between 32 000 years and 320 000 years (1012 seconds—a terasecond—and 1013 seconds). ... Spontaneous fission (SF) is a form of radioactive decay characteristic of very heavy isotopes, and is theoretically possible for any atomic nucleus whose mass is greater than or equal to 100 amu (elements near ruthenium). ... In nuclear physics, beta decay (sometimes called neutron decay) is a type of radioactive decay in which a beta particle (an electron or a positron) is emitted. ... This article is about the chemical element. ... A Synthetic radioisotope is a radionuclide that is not found in nature: no natural process or mechanism exists which produces it, or it is so unstable that it decays away in a very short period of time. ... To help compare orders of magnitude of different times this page lists times between 106 seconds (a megasecond) and 107 seconds (11. ... In nuclear physics, beta decay (sometimes called neutron decay) is a type of radioactive decay in which a beta particle (an electron or a positron) is emitted. ... General Name, Symbol, Number americium, Am, 95 Chemical series actinides Group, Period, Block n/a, 7, f Appearance silvery white sometimes yellow Standard atomic weight (243) g·mol−1 Electron configuration [Rn] 5f7 7s2 Electrons per shell 2, 8, 18, 32, 25, 8, 2 Physical properties Phase solid Density (near... Spontaneous fission (SF) is a form of radioactive decay characteristic of very heavy isotopes, and is theoretically possible for any atomic nucleus whose mass is greater than or equal to 100 amu (elements near ruthenium). ... A Synthetic radioisotope is a radionuclide that is not found in nature: no natural process or mechanism exists which produces it, or it is so unstable that it decays away in a very short period of time. ... To help compare orders of magnitude of different times this page lists times between 320 000 years and 3 200 000 years (1013 seconds and 1014 seconds) See also times of other orders of magnitude. ... This article is about the chemical element. ... 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This article is about metallic materials. ... Toxic redirects here, but this is also the name of a song by Britney Spears; see Toxic (song) Look up toxic and toxicity in Wiktionary, the free dictionary. ... The periodic table of the chemical elements A chemical element, or element, is a type of atom that is distinguished by its atomic number; that is, by the number of protons in its nucleus. ... See also: List of elements by atomic number In chemistry and physics, the atomic number (also known as the proton number) is the number of protons found in the nucleus of an atom. ... This article or section should include material from Fissile material In nuclear engineering, a fissile material is one that is capable of sustaining a chain reaction of nuclear fission. ... The mushroom cloud of the atomic bombing of Nagasaki, Japan, 1945, rose some 18 kilometers (11 mi) above the hypocenter A nuclear weapon derives its destructive force from nuclear reactions of fusion or fission. ... For other uses, see Isotope (disambiguation). ... Half-Life For a quantity subject to exponential decay, the half-life is the time required for the quantity to fall to half of its initial value. ... This article is about the chemical element. ... In physics a nucleon is a collective name for two baryons: the neutron and the proton. ... Earth cutaway from core to exosphere. ...

Notable characteristics

Plutonium has been called "the most complex metal" and "a physicist's dream but an engineer's nightmare"^[2] for its peculiar physical and chemical properties. It has six allotropes normally and a seventh under pressure. The allotropes have very similar energy levels but significantly varying densities, making plutonium very sensitive to changes in temperature, pressure, or chemistry, and allowing for dramatic volume changes following phase transitions (in nuclear applications, it is usually alloyed with a small amount of gallium, which stabilizes it in the delta-phase).^[3] Plutonium is silvery in pure form, but has a yellow tarnish when oxidized. It possesses a low-symmetry structure, causing it to become progressively more brittle over time.^[4] Because it self-irradiates, it ages both from the outside-in and the inside-out.^[3] However, self-irradiation can also lead to annealing which counteracts some of the aging effects. In general, the precise aging properties of plutonium are very complex and poorly understood, greatly complicating efforts to predict future reliability of weapons components. Allotropy (Gr. ... An alloy is a homogeneous hybrid of two or more elements, at least one of which is a metal, and where the resulting material has metallic properties. ... Not to be confused with Galium. ... The most fundamental reactions in chemistry are the redox processes. ... For other uses, see Annealing. ...

The heat given off by alpha particle emission makes plutonium warm to the touch in reasonable quantities. It displays five ionic oxidation states in aqueous solution: Alpha decay Alpha decay is a type of radioactive decay in which an atom emits an alpha particle (two protons and two neutrons bound together into a particle identical to a helium nucleus) and transforms (or decays) into an atom with a mass number 4 less and atomic number 2... In chemistry, the oxidation state is an indicator of the degree of oxidation of an atom in a chemical compound. ...

• Pu(III), as Pu³⁺ (blue lavender)
• Pu(IV), as Pu⁴⁺ (yellow brown)
• Pu(V), as PuO₂⁺ (thought to be pink; this ion is unstable in solution and will disproportionate into Pu⁴⁺ and PuO₂²⁺; the Pu⁴⁺ will then oxidize the remaining PuO₂⁺ to PuO₂²⁺, being reduced in turn to Pu³⁺. Thus, aqueous solutions of plutonium tend over time towards a mixture of Pu³⁺ and PuO₂²⁺.)^[5]
• Pu(VI), as PuO₂²⁺ (pink orange)
• Pu(VII), as PuO₅^2- (dark red); the heptavalent ion is rare and prepared only under extreme oxidizing conditions.

The actual color shown by Pu solutions depends on both the oxidation state and the nature of the acid anion, which influences the degree of complexing of the Pu species by the acid anion.^[6]

Applications

The isotope ²³⁹Pu is a key fissile component in nuclear weapons, due to its ease of fissioning and availability. The critical mass for an unreflected sphere of plutonium is 16 kg, but through the use of a neutron-reflecting tamper the pit of plutonium in a fission bomb is reduced to 10 kg, which is a sphere with a diameter of 10 cm. The Manhattan Project "Fat Man" type plutonium bombs, using explosive compression of Pu to significantly higher densities than normal, were able to function with plutonium cores of only 6.2 kg.^[7] Complete detonation may be achieved through the use of an additional neutron source (often from a small amount of fusion fuel). The Fat Man bomb had an explosive yield of 21 kilotons. (See also nuclear weapon design.) This article or section should include material from Fissile material In nuclear engineering, a fissile material is one that is capable of sustaining a chain reaction of nuclear fission. ... The mushroom cloud of the atomic bombing of Nagasaki, Japan, 1945, rose some 18 kilometers (11 mi) above the hypocenter A nuclear weapon derives its destructive force from nuclear reactions of fusion or fission. ... A sphere of plutonium surrounded by neutron-reflecting blocks of tungsten carbide. ... The first nuclear weapons, though large, cumbersome and inefficient, provided the basic design building blocks of all future weapons. ... Nuclear weapon designs are often divided into two classes, based on the dominant source of the nuclear weapons energy. ... This article is about the World War II nuclear project. ... This article is about the nuclear weapon used in World War II. For other uses, see Fat Man (disambiguation). ... This article is about the nuclear weapon used in World War II. For other uses, see Fat Man (disambiguation). ... The first nuclear weapons, though large, cumbersome and inefficient, provided the basic design building blocks of all future weapons. ...

The isotope plutonium-238 (²³⁸Pu) has a half-life of 88 years and emits a large amount of thermal energy as it decays. Being an alpha emitter, it combines high energy radiation with low penetration (thereby requiring minimal shielding). These characteristics make it well suited for electrical power generation for devices which must function without direct maintenance for timescales approximating a human lifetime. It is therefore used in radioisotope thermoelectric generators such as those powering the Cassini and New Horizons (Pluto) space probes; earlier versions of the same technology powered the ALSEP and EASEP systems including seismic experiments on the Apollo Moon missions. Plutonium 238, is an isotope of plutonium with a half-life of 86. ... In thermal physics, thermal energy is the energy portion of a system that increases with its temperature. ... An alpha particle is deflected by a magnetic field Alpha radiation consists of helium-4 nuclei and is readily stopped by a sheet of paper. ... A radioisotope thermoelectric generator (RTG) is a simple electrical generator which obtains its power from radioactive decay. ... This is an artists concept of Cassini during the Saturn Orbit Insertion (SOI) maneuver, just after the main engine has begun firing. ... For other uses, see New Horizons (disambiguation). ... The Apollo Lunar Surface Experiment Package, or ALSEP, was a set of connected scientific instruments left on the Moon when the Apollo program ended. ... ALSEP of the Apollo 16 mission The Apollo Lunar Surface Experiments Package (ALSEP) comprised a set of scientific instruments placed by the astronauts at the landing site of each of the five Apollo missions to land on the Moon following Apollo 11 (Apollos 12, 14, 15, 16, and 17). ... Seismology (from the Greek seismos(σεισμός) = earthquake and λόγος,logos = knowledge ) is the scientific study of earthquakes and the propagation of elastic waves through the Earth. ... This article is about the series of human spaceflight missions. ... This article is about Earths moon. ...

²³⁸Pu has been used successfully to power artificial heart pacemakers, to reduce the risk of repeated surgery.^{[citation needed]} It has been largely replaced by lithium-based primary cells, but as of 2003 there were somewhere between 50 and 100 plutonium-powered pacemakers still implanted and functioning in living patients. A pacemaker, scale in centimeters A pacemaker (or artificial pacemaker, so as not to be confused with the hearts natural pacemaker) is a medical device which uses electrical impulses, delivered by electrodes contacting the heart muscles, to regulate the beating of the heart. ... This article is about the chemical element. ... A primary cell is any kind of electrolytic cell in which the electrochemical reaction of interest is not reversible. ... 2003 is a common year starting on Wednesday of the Gregorian calendar, and also: The International Year of Freshwater The European Disability Year Events January events January 1 Luíz Inácio Lula Da Silva becomes the 37th President of Brazil. ...

History

Glenn Seaborg at the Geiger Counter, 301 Gilman Hall, Berkeley, California, where he discovered plutonium.

The production of plutonium and neptunium by bombarding uranium-238 with neutrons was predicted in 1940 by two teams working independently: Edwin M. McMillan and Philip Abelson at Berkeley Radiation Laboratory at the University of California, Berkeley; and by Egon Bretscher and Norman Feather at the Cavendish Laboratory of the University of Cambridge for the Tube Alloys project.^{[citation needed]} Coincidentally both teams proposed the same names to follow on from uranium, following the sequence of the outer planets.^{[citation needed]} Image File history File links Seaborg_Geiger_Gilman_Hall. ... Image File history File links Seaborg_Geiger_Gilman_Hall. ... Glenn Theodore Seaborg (April 19, 1912 – February 25, 1999) was an American atomic scientist. ... Gilman Hall is a building on the campus of the University of California, Berkeley. ... General Name, Symbol, Number neptunium, Np, 93 Chemical series actinides Group, Period, Block n/a, 7, f Appearance silvery metallic Standard atomic weight (237) g·mol−1 Electron configuration [Rn] 5f4 6d1 7s2 Electrons per shell 2, 8, 18, 32, 22, 9, 2 Physical properties Phase solid Density (near r. ... There are two objects with this name: Unterseeboot 238 Uranium-238, the most common isotope of uranium This is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ... Edwin Mattison McMillan (September 18, 1907-September 7, 1991) was the first scientist to produce a transuranium element. ... Philip Hauge Abelson (April 27, 1913 - August 1, 2004) was a physicist, editor of scientific literature, and science writer. ... The Berkeley Lab is perched on a hill overlooking the Berkeley central campus and San Francisco Bay. ... Sather Tower (the Campanile) looking out over the San Francisco Bay and Mount Tamalpais. ... Plaque, at old site Entrance, old site, Free School Lane The Cavendish Laboratory is the University of Cambridges Department of Physics, and is part of the universitys School of Physical Sciences. ... The University of Cambridge (often Cambridge University), located in Cambridge, England, is the second-oldest university in the English-speaking world and has a reputation as one of the most prestigious universities in the world. ... // Tube Alloys was the code-name for the British nuclear weapon programme during World War II, when the very possibility of nuclear weapons was kept at such a high level of secrecy that it had to be referred to by code even in the highest circles of government. ...

First isolation

Plutonium was first produced and isolated on December 14, 1940 by Dr. Glenn T. Seaborg, Edwin M. McMillan, J. W. Kennedy, Z. M. Tatom^{[citation needed]}, and A. C. Wahl by deuteron bombardment of uranium in the 60-inch cyclotron at Berkeley. The discovery was kept secret due to the war. It was named after Pluto, having been discovered directly after neptunium (which itself was one higher on the periodic table than uranium), by analogy to solar system planet order as Pluto was considered to be a planet at the time (though technically it should have been "plutium", Seaborg said that he did not think it sounded as good as "plutonium"). Seaborg chose the letters "Pu" as a joke, which passed without notice into the periodic table.^[8] Originally, Seaborg and others thought about naming the element "ultinium" or "extremium" because they believed at the time that they had found the last possible element on the periodic table.^[9] is the 348th day of the year (349th in leap years) in the Gregorian calendar. ... Year 1940 (MCMXL) was a leap year starting on Monday (link will display the full 1940 calendar) of the Gregorian calendar. ... Glenn Theodore Seaborg (April 19, 1912 – February 25, 1999) won the 1951 Nobel Prize in Chemistry for discoveries in the chemistry of the transuranium elements,[1] contributed to the discovery and isolation of ten elements, developed the actinide concept and was the first to propose the actinide series which led... Edwin Mattison McMillan (September 18, 1907-September 7, 1991) was the first scientist to produce a transuranium element. ... Joseph W. Kennedy (May 30, 1916 – May 5, 1957) is credited with being a co-discoverer of Plutonium along with Glenn T. Seaborg, Edwin McMillan, and Arthur Wahl. ... Arthur Wahl (September 8, 1917 – April, 2006) was an American physicist who, as a graduate student in February 1941, was the first to isolate plutonium in a laboratory. ... Deuterium (symbol 2H) is a stable isotope of hydrogen with a natural abundance of one atom in 6500 of hydrogen. ... Combatants Allied powers: China France Great Britain Soviet Union United States and others Axis powers: Germany Italy Japan and others Commanders Chiang Kai-shek Charles de Gaulle Winston Churchill Joseph Stalin Franklin Roosevelt Adolf Hitler Benito Mussolini Hideki Tōjō Casualties Military dead: 17,000,000 Civilian dead: 33,000... For other uses, see Pluto (disambiguation). ... General Name, Symbol, Number neptunium, Np, 93 Chemical series actinides Group, Period, Block n/a, 7, f Appearance silvery metallic Standard atomic weight (237) g·mol−1 Electron configuration [Rn] 5f4 6d1 7s2 Electrons per shell 2, 8, 18, 32, 22, 9, 2 Physical properties Phase solid Density (near r. ... This article is about the chemical element. ... The periodic table of the chemical elements A chemical element, or element, is a type of atom that is distinguished by its atomic number; that is, by the number of protons in its nucleus. ... The Periodic Table redirects here. ...

Chemists at the University of Chicago began to study the newly manufactured radioactive element. The George Herbert Jones Laboratory at the university was the site where, on 18 August 1942, a trace quantity of this new element was isolated and measured for the first time. This procedure enabled chemists to determine the new element's atomic weight. Room 405 of the building was named a National Historic Landmark in May 1967.^[10] For other uses, see University of Chicago (disambiguation). ... The George Herbert Jones Laboratory, at 5747 S. Ellis Avenue, Chicago, Illinois, is a facility building of the University of Chicago. ... This article or section needs additional references or sources to improve its verifiability. ...

During the Manhattan Project, plutonium was also often referred, simply, to as "49". Number 4 was for the last digit in 94 (atomic number of plutonium) and 9 for the last digit in Pu-239, the weapon-grade fissile isotope used in nuclear bombs. ^{[11] [12]}

Production

During the Manhattan Project, the first production reactor, the X-10 Graphite Reactor, was built at the Oak Ridge, Tennessee site that became Oak Ridge National Laboratory. Later, large (200MWt) reactors were set up at the Hanford Site (near Richland, Washington), for the production of plutonium, which was used in the first atomic bomb used at the "Trinity" test in July 1945. Plutonium was also used in the "Fat Man" bomb dropped on Nagasaki, Japan in August 1945. The "Little Boy" bomb dropped on Hiroshima utilized uranium-235, not plutonium. This article is about the World War II nuclear project. ... When President Roosevelt in December 1942 authorized the Manhattan Project, the Oak Ridge site in eastern Tennessee had already been obtained and plans laid for an air-cooled experimental pile, a pilot chemical separation plant, and support facilities. ... Oak Ridge is an incorporated city in Anderson and Roane Counties in East Tennessee, about 25 miles northwest of Knoxville. ... This article is about the U.S. state of Tennessee. ... A combination of federal, state and private funds is providing $300 million for the construction of 13 facilities on ORNLs new main campus. ... Core of a small nuclear reactor used for research. ... Hanford Site plutonium production reactors along the Columbia River during the Manhattan Project. ... Richland Police Station in foreground. ... The Trinity test was the first test of a nuclear weapon, conducted by the United States on July 16, 1945 at , thirty miles (48 km) southeast of Socorro on what is now White Sands Missile Range, headquartered near Alamogordo, New Mexico. ... This article is about the nuclear weapon used in World War II. For other uses, see Fat Man (disambiguation). ... Megane-bashi (Spectacles Bridge) Nagasaki   listen? (長崎市; -shi, literally long peninsula) is the capital and the largest city of Nagasaki Prefecture located at the south-western coast of Kyushu, Japan. ... Little Boy was the codename of the atomic bomb which was dropped on Hiroshima, on August 6, 1945 by the 12-man crew of the B-29 Superfortress Enola Gay, piloted by Colonel Paul Tibbets (Tibbets, age 92, died Nov. ... For other uses, see Hiroshima (disambiguation). ... Uranium-235 is an isotope of uranium that differs from the elements other common isotope, uranium-238, by its ability to cause a rapidly expanding fission chain reaction. ...

Large stockpiles of "weapons-grade" plutonium were built up by both the Soviet Union and the United States during the Cold War. The U.S. reactors at Hanford and the Savannah River Site in South Carolina produced 103,000 kg;^[13] It was estimated there are another 170,000 kg of military plutonium in Russia, with 300,000 kg accumulated worldwide. ^[14] Since the end of the Cold War, these stockpiles have become a focus of nuclear proliferation concerns. In 2002, the United States Department of Energy took possession of 34 metric tons of excess weapons-grade plutonium stockpiles from the United States Department of Defense, and as of early 2003 was considering converting several nuclear power plants in the US from enriched uranium fuel to MOX fuel as a means of disposing of plutonium stocks. For other uses, see Cold War (disambiguation). ... Hanford Site plutonium production reactors along the Columbia River during the Manhattan Project. ... The Savannah River Site is a nuclear materials processing center in the US state of South Carolina, located on land adjacent to the Savannah River near Augusta, Georgia. ... World map with nuclear weapons development status represented by color. ... The United States Department of Energy (DOE) is a Cabinet-level department of the United States government responsible for energy policy and nuclear safety. ... The United States Department of Defense (DOD or DoD) is the federal department charged with coordinating and supervising all agencies and functions of the government relating directly to national security and the military. ... These pie-graphs showing the relative proportions of uranium-238 (blue) and uranium-235 (red) at different levels of enrichment. ... Mixed oxide, or MOX fuel, is a blend of plutonium and natural uranium or depleted uranium which behaves similarly (though not identically) to the enriched uranium feed for which most nuclear reactors were designed. ...

Hanford Site plutonium production reactors along the Columbia River during the Manhattan Project.

Hanford Site, 1945, from the Smyth Report. ... Hanford Site, 1945, from the Smyth Report. ... The Columbia River (French: fleuve Columbia) is a river in the Pacific Northwest region of North America. ... This article is about the World War II nuclear project. ...

Medical experimentation

During the initial years after the discovery of plutonium, when its biological and physical properties were very poorly understood, a series of human radiation experiments were performed by the U.S. government and by private organizations acting on its behalf. During and after the end of World War II, scientists working on the Manhattan Project and other nuclear weapons research projects conducted studies of the effects of plutonium on laboratory animals and human subjects. In the case of human subjects, this involved injecting solutions containing (typically) five micrograms of plutonium into hospital patients thought to be either terminally ill, or to have a life expectancy of less than ten years either due to age or chronic disease condition. These eighteen injections were made without the informed consent of those patients and were not done with the belief that the injections would heal their conditions; rather, they were used to develop diagnostic tools for determining the uptake of plutonium in the body for use in developing safety standards for people working with plutonium during the course of developing nuclear weapons.^[15] Since the discovery of ionizing radiation, a number of human radiation experiments have been performed to understand the effects of ionizing radiation and radioactive contamination on the human body. ... This article is about the World War II nuclear project. ... Informed consent is a legal condition whereby a person can be said to have given consent based upon an appreciation and understanding of the facts and implications of an action. ...

The episode is now considered to be a serious breach of medical ethics and of the Hippocratic Oath, and has been sharply criticised as failing "both the test of our national values and the test of humanity."^[16] More sympathetic commentators have noted that while it was definitely a breach in trust and ethics, "the effects of the plutonium injections were not as damaging to the subjects as the early news stories painted, nor were they so inconsequential as many scientists, then and now, believe."^[17] For other uses, see Hippocratic Oath (disambiguation). ...

Occurrence

While almost all plutonium is manufactured synthetically, extremely tiny trace amounts are found naturally in uranium ores. These come about by a process of neutron capture by ²³⁸U nuclei, initially forming ²³⁹U; two subsequent beta decays then form ²³⁹Pu (with a ²³⁹Np intermediary), which has a half-life of 24,110 years. This is also the process used to manufacture ²³⁹Pu in nuclear reactors. Some traces of ²⁴⁴Pu remain^{[citation needed]} from the birth of the solar system from the waste of supernovae, because its half-life of 80 million years is fairly long. This article is about the chemical element. ... The process of neutron capture can proceed in two ways - as a rapid process (an r-process) or a slow process (an s-process). ... In nuclear physics, beta decay (sometimes called neutron decay) is a type of radioactive decay in which a beta particle (an electron or a positron) is emitted. ... General Name, Symbol, Number neptunium, Np, 93 Chemical series actinides Group, Period, Block n/a, 7, f Appearance silvery metallic Standard atomic weight (237) g·mol−1 Electron configuration [Rn] 5f4 6d1 7s2 Electrons per shell 2, 8, 18, 32, 22, 9, 2 Physical properties Phase solid Density (near r. ... Core of a small nuclear reactor used for research. ...

A relatively high concentration of plutonium was discovered at the natural nuclear fission reactor in Oklo, Gabon in 1972. Since 1945, approximately 7700 kg has been released onto Earth through nuclear explosions. Natural Reactors refer to a handful of Uranium deposits that have been discovered, mostly in Oklo, Gabon. ... Oklo is a place in the West African state of Gabon. ... This article is about Earth as a planet. ... A nuclear explosion (nuclear detonation) has occurred: twice using a nuclear weapon during war (during World War II, the atomic bombings of Hiroshima and Nagasaki) many times testing a nuclear weapon a series of tests of nuclear explosives for construction purposes; see Operation Plowshare Potential other applications (not yet applied...

Manufacture

Pu-240, Pu-241 and Pu-242

The activation cross section for ²³⁹Pu is 270 barns, while the fission cross section is 747 barns for thermal neutrons. The higher plutonium isotopes are created when the uranium fuel is used for a long time. It is the case that for high burnup used fuel that the concentrations of the higher plutonium isotopes will be higher than the low burnup fuel which is reprocessed to obtain bomb grade plutonium. Cross section may refer to the following In geometry, Cross section is the intersection of a 3-dimensional body with a plane. ... A barn (symbol b) is a unit of area. ...

This article does not cite its references or sources. ... Cross section may refer to the following In geometry, Cross section is the intersection of a 3-dimensional body with a plane. ... In physics, the decay mode describes a particular way a particle decays. ... Half-Life For a quantity subject to exponential decay, the half-life is the time required for the quantity to fall to half of its initial value. ... This article is about the chemical element. ... This article is about the chemical element. ... General Name, Symbol, Number neptunium, Np, 93 Chemical series actinides Group, Period, Block n/a, 7, f Appearance silvery metallic Standard atomic weight (237) g·mol−1 Electron configuration [Rn] 5f4 6d1 7s2 Electrons per shell 2, 8, 18, 32, 22, 9, 2 Physical properties Phase solid Density (near r. ...

Pu-239

Main article: Plutonium-239

Plutonium-239 is one of the three fissile materials used for the production of nuclear weapons and in some nuclear reactors as a source of energy. The other fissile materials are uranium-235 and uranium-233. Plutonium-239 is virtually nonexistent in nature. It is made by bombarding uranium-238 with neutrons in a nuclear reactor. Uranium-238 is present in quantity in most reactor fuel; hence plutonium-239 is continuously made in these reactors. Since plutonium-239 can itself be split by neutrons to release energy, plutonium-239 provides a portion of the energy generation in a nuclear reactor. General Name, Symbol, Number plutonium, Pu, 94 Chemical series actinides Group, Period, Block ?, 7, f Appearance silvery white Atomic mass (244) g/mol Electron configuration [Rn] 5f6 7s2 Electrons per shell 2, 8, 18, 32, 24, 8, 2 Physical properties Phase solid Density (near r. ... This article or section should include material from Fissile material In nuclear engineering, a fissile material is one that is capable of sustaining a chain reaction of nuclear fission. ... The mushroom cloud of the atomic bombing of Nagasaki, Japan, 1945, rose some 18 kilometers (11 mi) above the hypocenter A nuclear weapon derives its destructive force from nuclear reactions of fusion or fission. ... Core of a small nuclear reactor used for research. ... Uranium-235 is an isotope of uranium that differs from the elements other common isotope, uranium-238, by its ability to cause a rapidly expanding fission chain reaction. ... Uranium-233 is a fissile artificial isotope of uranium, which is proposed as a nuclear fuel. ... There are two objects with this name: Unterseeboot 238 Uranium-238, the most common isotope of uranium This is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ... This article or section does not adequately cite its references or sources. ...

A ring of weapons-grade electrorefined plutonium, with 99.96% purity. This 5.3 kg ring is enough plutonium for use in an efficient nuclear weapon.

Image File history File linksMetadata Download high-resolution version (1295x1231, 2174 KB) A weapons-grade ring of electrorefined plutonium, typical of the rings refined at Los Alamos and sent to Rocky Flats for fabrication. ... Image File history File linksMetadata Download high-resolution version (1295x1231, 2174 KB) A weapons-grade ring of electrorefined plutonium, typical of the rings refined at Los Alamos and sent to Rocky Flats for fabrication. ... This article does not cite its references or sources. ... Cross section may refer to the following In geometry, Cross section is the intersection of a 3-dimensional body with a plane. ... In physics, the decay mode describes a particular way a particle decays. ... Half-Life For a quantity subject to exponential decay, the half-life is the time required for the quantity to fall to half of its initial value. ... This article is about the chemical element. ... This article is about the chemical element. ... General Name, Symbol, Number neptunium, Np, 93 Chemical series actinides Group, Period, Block n/a, 7, f Appearance silvery metallic Standard atomic weight (237) g·mol−1 Electron configuration [Rn] 5f4 6d1 7s2 Electrons per shell 2, 8, 18, 32, 22, 9, 2 Physical properties Phase solid Density (near r. ...

Pu-238

Main article: Plutonium-238

There are small amounts of Pu-238 in the plutonium of usual plutonium-producing reactors. However, isotopic separation would be quite expensive compared to another method: when a U-235 atom captures a neutron, it is converted to an excited state of U-236. Some of the excited U-236 nuclei undergo fission, but some decay to the ground state of U-236 by emitting gamma radiation. Further neutron capture creates U-237 which has a half-life of 7 days and thus quickly decays to Np-237. Since nearly all neptunium is produced in this way or consists of isotopes which decay quickly, one gets nearly pure Np-237 by chemical separation of neptunium. After this chemical separation, Np-237 is again irradiated by reactor neutrons to be converted to Np-238 which decays to Pu-238 with a half-life of 2 days. Plutonium 238, is an isotope of plutonium with a half-life of 86. ... General Name, Symbol, Number neptunium, Np, 93 Chemical series actinides Group, Period, Block n/a, 7, f Appearance silvery metallic Standard atomic weight (237) g·mol−1 Electron configuration [Rn] 5f4 6d1 7s2 Electrons per shell 2, 8, 18, 32, 22, 9, 2 Physical properties Phase solid Density (near r. ...

This article does not cite its references or sources. ... Cross section may refer to the following In geometry, Cross section is the intersection of a 3-dimensional body with a plane. ... In physics, the decay mode describes a particular way a particle decays. ... Half-Life For a quantity subject to exponential decay, the half-life is the time required for the quantity to fall to half of its initial value. ... This article is about the chemical element. ... This article is about the chemical element. ... This article is about the chemical element. ... General Name, Symbol, Number neptunium, Np, 93 Chemical series actinides Group, Period, Block n/a, 7, f Appearance silvery metallic Standard atomic weight (237) g·mol−1 Electron configuration [Rn] 5f4 6d1 7s2 Electrons per shell 2, 8, 18, 32, 22, 9, 2 Physical properties Phase solid Density (near r. ... General Name, Symbol, Number neptunium, Np, 93 Chemical series actinides Group, Period, Block n/a, 7, f Appearance silvery metallic Standard atomic weight (237) g·mol−1 Electron configuration [Rn] 5f4 6d1 7s2 Electrons per shell 2, 8, 18, 32, 22, 9, 2 Physical properties Phase solid Density (near r. ...

Compounds

Image showing colors of various oxidation states of Pu in solution on the left and colors of only one Pu oxidation state (IV) on the right in solutions containing different anions.

Plutonium reacts readily with oxygen, forming PuO and PuO₂, as well as intermediate oxides. It reacts with the halogens, giving rise to compounds such as PuX₃ where X can be F, Cl, Br or I; PuF₄ and PuF₆ are also seen. The following oxyhalides are observed: PuOCl, PuOBr and PuOI. It will react with carbon to form PuC, nitrogen to form PuN and silicon to form PuSi₂. Download high resolution version (1240x511, 65 KB)Various colors of plutonium in solution. ... Download high resolution version (1240x511, 65 KB)Various colors of plutonium in solution. ... This article is about the chemical element and its most stable form, or dioxygen. ... Prepared during the reprocessing of nuclear fuel by calcination of plutonium(IV) oxalate, Pu(C2O4)2. ... This article is about the chemical series. ... Plutonium fluoride (PuF4), As for all plutonium compounds, subject to control under the Nuclear Non-Proliferation Treaty. ... For other uses, see Carbon (disambiguation). ... General Name, symbol, number nitrogen, N, 7 Chemical series nonmetals Group, period, block 15, 2, p Appearance colorless gas Standard atomic weight 14. ... Not to be confused with Silicone. ...

Plutonium like other actinides readily forms a dioxide plutonyl core (PuO₂). In the environment, this plutonyl core readily complexes with carbonate as well as other oxygen moieties (OH^-, NO₂^-, NO₃^-, and SO₄^-2) to form charged complexes which can be readily mobile with low affinities to soil.

• PuO₂(CO₃)₁^-2
• PuO₂(CO₃)₂^-4
• PuO₂(CO₃)₃^-6

PuO₂ formed from neutralizing highly acidic nitric acid solutions tends to form polymeric PuO₂ which is resistant to complexation. Plutonium also readily shifts valences between the +3, +4, +5 and +6 states. It is common for some fraction of plutonium in solution to exist in all of these states in equilibrium.

Allotropes

Main article: Allotropes of plutonium

A diagram of the allotropes of plutonium at ambient pressure

Even at ambient pressure, plutonium occurs in a variety of allotropes. These allotropes differ widely in crystal structure and density; the α and δ allotropes differ in density by more than 25% at constant pressure. Phase diagram for plutonium at ambient pressure. ... Allotropy (Gr. ...

The presence of these many allotropes makes machining plutonium very difficult, as it changes state very readily. The reasons for the complicated phase diagram are not entirely understood; recent research has focused on constructing accurate computer models of the phase transitions. This diagram shows the nomenclature for the different phase transitions. ...

In weapons applications, plutonium is often alloyed with another metal (e.g., delta phase with a small percentage of gallium) to increase phase stability and thereby enhance workability and ease of handling. Interestingly, in fission weapons, the explosive shock waves used to compress a plutonium core will also cause a transition from the usual delta phase plutonium to the denser alpha phase, significantly helping to achieve supercriticality. An alloy is a homogeneous hybrid of two or more elements, at least one of which is a metal, and where the resulting material has metallic properties. ... Not to be confused with Galium. ... Introduction The shock wave is one of several different ways in which a gas in a supersonic flow can be compressed. ... For example, one neutron would hit the nucleus, causing two neutrons to be released, which would then hit the next nucleus, causing four neutrons to be released, and so on. ...

Isotopes

Main article: Isotopes of plutonium

Twenty-one plutonium radioisotopes have been characterized. The most stable are Pu-244, with a half-life of 80.8 million years, Pu-242, with a half-life of 373,300 years, and Pu-239, with a half-life of 24,110 years. Because of its comparatively large half-life, minute amounts of Pu-244 can be found in nature^[18], All of the remaining radioactive isotopes have half-lives that are less than 7,000 years. This element also has eight meta states, though none are very stable (all have half-lives less than one second). Plutonium (Pu) Has no stable isotopes. ... A radionuclide is an atom with an unstable nucleus. ... Half-Life For a quantity subject to exponential decay, the half-life is the time required for the quantity to fall to half of its initial value. ... Radioactive decay is the set of various processes by which unstable atomic nuclei (nuclides) emit subatomic particles. ... A nuclear isomer is a metastable state of an atom caused by the excitation of a proton or neutron in its nucleus so that it requires a change in spin before it can release its extra energy. ...

The isotopes of plutonium range in atomic weight from 228.0387 u (Pu-228) to 247.074 u (Pu-247). The primary decay modes before the most stable isotope, Pu-244, are spontaneous fission and alpha emission; the primary mode after is beta emission. The primary decay products before Pu-244 are uranium and neptunium isotopes (neglecting the wide range of daughter nuclei created by fission processes), and the primary products after are americium isotopes. ... The unified atomic mass unit (u), or dalton (Da), is a small unit of mass used to express atomic and molecular masses. ... In physics, the decay mode describes a particular way a particle decays. ... Spontaneous fission (SF) is a form of radioactive decay characteristic of very heavy isotopes, and is theoretically possible for any atomic nucleus whose mass is greater than or equal to 100 amu (elements near ruthenium). ... Alpha decay is a form of radioactive decay in which an atomic nucleus ejects an alpha particle and transforms into a nucleus with mass number 4 less and atomic number 2 less. ... In nuclear physics, beta decay (sometimes called neutron decay) is a type of radioactive decay in which a beta particle (an electron or a positron) is emitted. ... In nuclear physics, a decay product, also known as a daughter product, is a nuclide resulting from the radioactive decay of a parent or precursor nuclide. ... General Name, Symbol, Number americium, Am, 95 Chemical series actinides Group, Period, Block n/a, 7, f Appearance silvery white sometimes yellow Standard atomic weight (243) g·mol−1 Electron configuration [Rn] 5f7 7s2 Electrons per shell 2, 8, 18, 32, 25, 8, 2 Physical properties Phase solid Density (near...

A pellet of plutonium-238, glowing due to blackbody radiation, used for radioisotope thermoelectric generators.

Key isotopes for applications are Pu-239, which is suitable for use in nuclear weapons and nuclear reactors, and Pu-238, which is suitable for use in radioisotope thermoelectric generators; see above for more details. The isotope Pu-240 undergoes spontaneous fission very readily, and is produced when Pu-239 is exposed to neutrons. The presence of Pu-240 in a material limits its nuclear bomb potential since it emits neutrons randomly, increasing the difficulty of initiating accurately the chain reaction at the desired instant and thus reducing the bomb's reliability and power. Plutonium consisting of more than about 90% Pu-239 is called weapons-grade plutonium; plutonium obtained from commercial reactors generally contains at least 20% Pu-240 and is called reactor-grade plutonium. Image File history File linksMetadata Download high-resolution version (3200x2560, 2212 KB) Plutonium-238 sphere under its own light. ... Image File history File linksMetadata Download high-resolution version (3200x2560, 2212 KB) Plutonium-238 sphere under its own light. ... As the temperature decreases, the peak of the black body radiation curve moves to lower intensities and longer wavelengths. ... // A radioisotope thermoelectric generator (RTG) is a simple electrical generator which obtains its power from radioactive decay. ... A radioisotope thermoelectric generator (RTG) is a simple electrical generator which obtains its power from radioactive decay. ... A chain reaction is a sequence of reactions where a reactive product or by-product causes additional reactions. ... Weapons-grade means that a substance is pure enough to be used to make a weapon or has properties that make it suitable for weapons use. ...

Pu-240, while of little importance by itself, plays a crucial role as a contaminant in plutonium used in nuclear weapons. It spontaneously fissions at a high rate, and a 1% impurity in Pu-239 will lead to unacceptably early initiation of a fission chain reaction in gun-type atomic weapons (e.g. the proposed Thin Man bomb), blowing the weapon apart before much of its material can fission. Pu-240 contamination is the reason plutonium weapons must use an implosion design. A theoretical 100% pure Pu-239 weapon could be constructed as a gun-type device, but achieving this level of purity is prohibitively difficult. Pu-240 contamination has proven a mixed blessing to weapons designers. While it created delays and headaches during the Manhattan Project because of the need to develop implosion technology, those very same difficulties are currently a barrier to nuclear proliferation. Implosion devices are also inherently more efficient and less prone toward accidental detonation than are gun-type weapons. Thin Man plutonium gun test casings at Wendover Army Air Field, as part of Project Alberta in the Manhattan Project. ...

Precautions

Toxicity

Glowing hot bits of plutonium in a box, which have been set alight due to plutonium's pyrophoric nature.

All isotopes and compounds of plutonium are toxic and radioactive. While plutonium is sometimes described in media reports as "the most toxic substance known to man", from the standpoint of actual chemical or radiological toxicity this is incorrect. When taken in by mouth, plutonium is less poisonous than if inhaled, since it is not absorbed into the body efficiently when ingested. The U.S. Department of Energy estimates the increase in lifetime cancer risk for inhaled plutonium as 3×10⁻⁸ pCi⁻¹.^[19] (this means that inhaling 1 μCi, or about 2.5 μg of reactor-grade plutonium is estimated to increase one's lifetime risk of developing cancer as a result of the exposure to 3%). When plutonium is absorbed into the body, it is excreted very slowly, with a biological half-life of 200 years.^[20] From a purely chemical standpoint, it is about as poisonous as lead and other heavy metals.^{[citation needed]} Not surprisingly, it has a metallic taste.^[21] Image File history File linksMetadata Download high-resolution version (2811x1883, 3605 KB) Plutonium pyrophoricity (spontaneously burning in contact with air, causes it to glow like an ember). ... Image File history File linksMetadata Download high-resolution version (2811x1883, 3605 KB) Plutonium pyrophoricity (spontaneously burning in contact with air, causes it to glow like an ember). ... Molten glassy material glows orange with incandescence in a vitrification experiment. ... A pyrophoric substance is a substance that ignites spontaneously, that is, its autoignition temperature is below room temperature. ... For other uses, see Toxin (disambiguation). ... // Toxic and Intoxicated redirect here – toxic has other uses, which can be found at Toxicity (disambiguation); for the state of being intoxicated by alcohol see Drunkenness. ... The biological half-life of a substance is the time required for half of that substance to be removed from an organism by either a physical or a chemical process. ... General Name, Symbol, Number lead, Pb, 82 Chemical series Post-transition metals or poor metals Group, Period, Block 14, 6, p Appearance bluish gray Standard atomic weight 207. ... For other uses, see Heavy metal (disambiguation). ...

Plutonium may be extremely dangerous when handled incorrectly. The alpha radiation it emits does not penetrate the skin, but can irradiate internal organs when plutonium is inhaled or ingested. Particularly at risk are the skeleton, where it is likely to be absorbed by the bone surface, and the liver, where it will likely collect and become concentrated. Approximately 0.008 microcuries absorbed in bone marrow is the maximum withstandable dose. Anything more is considered toxic. Extremely fine particles of plutonium (on the order of micrograms) can cause lung cancer if inhaled.^{[citation needed]} An alpha particle is deflected by a magnetic field Alpha radiation consists of helium-4 nuclei and is readily stopped by a sheet of paper. ... For other uses, see Skeleton (disambiguation). ... The liver is the largest internal organ in the human body, and is an organ present in vertebrates and some other animals. ... Lung cancer is a disease of uncontrolled cell growth in tissues of the lung. ...

Other substances including ricin, tetrodotoxin, botulinum toxin, and tetanus toxin are fatal in doses of (sometimes far) under one milligram, and others (the nerve agents, the amanita toxin) are in the range of a few milligrams. As such, plutonium is not unusual in terms of toxicity, even by inhalation. In addition, those substances are fatal in hours to days, whereas plutonium (and other cancer-causing radioactives) give an increased chance of illness decades in the future. Considerably larger amounts may cause acute radiation poisoning and death if ingested or inhaled; however, so far, no human is known to have immediately died because of inhaling or ingesting plutonium and many people have measurable amounts of plutonium in their bodies.^{[citation needed]} Castor beans Ricin (pronounced ) is a protein toxin that is extracted from the castor bean (Ricinus communis). ... Tetrodotoxin (anhydrotetrodotoxin 4-epitetrodotoxin, tetrodonic acid, TTX) is a potent neurotoxin with no known antidote, which blocks action potentials in nerves by binding to the pores of the voltage-gated, fast sodium channels in nerve cell membranes. ... Botulin toxin or botox is the toxic compound produced by the bacterium Clostridium botulinum. ... Tetanus is a medical condition that is characterized by a prolonged contraction of skeletal muscle fibers. ... This article is about the chemical. ... Species 600, see List of Amanita species Synonyms Aspidella The genus Amanita contains about 600 species of agarics including some of the most toxic known mushrooms found worldwide. ... Radiation poisoning, also called radiation sickness or a creeping dose, is a form of damage to organ tissue due to excessive exposure to ionizing radiation. ...

Disposal difficulties

In contrast to naturally occurring radioisotopes such as radium or C-14, plutonium was manufactured, concentrated, and isolated in large amounts (hundreds of metric tons) during the Cold War for weapons production. These stockpiles, whether or not in weapons form, pose a significant problem because, unlike chemical or biological agents, no chemical process can destroy them. One proposal to dispose of surplus weapons-grade plutonium is to mix it with highly radioactive isotopes (e.g., spent reactor fuel) to deter handling by potential thieves or terrorists. Another is to mix it with uranium and use it to fuel nuclear power reactors (the mixed oxide or MOX approach). This would not only fission (and thereby destroy) much of the Pu-239, but also transmute a significant fraction of the remainder into Pu-240 and heavier isotopes that would make the resulting mixture useless for nuclear weapons.^[22] For other uses, see Radium (disambiguation). ... Carbon-14 is the radioactive isotope of carbon discovered February 27, 1940, by Martin Kamen and Sam Ruben. ... For other uses, see Cold War (disambiguation). ... The Mox are a alien race that inhabit Planet X, they are divided into clans which seem to be forever at war. ...

Criticality potential

Toxicity issues aside, care must be taken to avoid the accumulation of amounts of plutonium which approach critical mass, particularly because plutonium's critical mass is only a third of that of uranium-235's. Despite not being confined by external pressure as is required for a nuclear weapon, it will nevertheless heat itself and break whatever confining environment it is in. Shape is relevant; compact shapes such as spheres are to be avoided. Plutonium in solution is more likely to form a critical mass than the solid form (due to moderation by the hydrogen in water). A weapon-scale nuclear explosion cannot occur accidentally, since it requires a greatly supercritical mass in order to explode rather than simply melt or fragment. However, a marginally critical mass will cause a lethal dose of radiation and has in fact done so in the past on several occasions. A sphere of plutonium surrounded by neutron-reflecting blocks of tungsten carbide. ...

Criticality accidents have occurred in the past, some of them with lethal consequences. Careless handling of tungsten carbide bricks around a 6.2 kg plutonium sphere resulted in a lethal dose of radiation at Los Alamos on August 21, 1945, when scientist Harry K. Daghlian, Jr. received a dose estimated to be 510 rems (5.1 Sv) and died four weeks later. Nine months later, another Los Alamos scientist, Louis Slotin, died from a similar accident involving a beryllium reflector and the same plutonium core (the so-called "demon core") that had previously claimed the life of Daghlian. These incidents were fictionalized in the 1989 film Fat Man and Little Boy. In 1958, during a process of purifying plutonium at Los Alamos, a critical mass was formed in a mixing vessel, which resulted in the death of a crane operator. Other accidents of this sort have occurred in the Soviet Union, Japan, and many other countries. (See List of nuclear accidents.) The 1986 Chernobyl accident caused a minor release of plutonium.^{[citation needed]} A criticality accident (also sometimes referred to as an excursion or power excursion) occurs when a nuclear chain reaction is accidentally allowed to occur in fissile material, such as enriched uranium or plutonium. ... Los Alamos National Laboratory, aerial view from 1995. ... is the 233rd day of the year (234th in leap years) in the Gregorian calendar. ... Year 1945 (MCMXLV) was a common year starting on Monday (link will display the full calendar). ... Harry K. Daghlian, Jr. ... The Röntgen equivalent man or rem (symbol rem) is an obsolete unit of radiation dose. ... The sievert (symbol: Sv) is the SI derived unit of dose equivalent. ... A sketch used by doctors to determine the amount of radiation to which each person in the room had been exposed during the excursion. ... The Demon core was the nickname given to a 6. ... Fat Man and Little Boy (aka Shadow Makers in the UK) is a 1989 film that reenacts the Manhattan Project, the secret Allied endeavor to develop the first nuclear weapons during World War II. It is named after the nuclear weapons known as Fat Man and Little Boy, and also... Pathways from airborne radioactive contamination to man This article covers notable accidents involving nuclear material. ... The nuclear power plant at Chernobyl prior to the completion of the sarcophagus. ... To meet Wikipedias quality standards, this article may require cleanup. ...

Flammability

Metallic plutonium is also a fire hazard, especially if the material is finely divided. It reacts chemically with oxygen and water, which may result in an accumulation of plutonium hydride, a pyrophoric substance; that is, a material that will ignite in air at room temperature. Plutonium expands considerably in size as it oxidizes and thus may break its container. The radioactivity of the burning material is an additional hazard. Magnesium-oxide sand is the most effective material for extinguishing a plutonium fire. It cools the burning material, acting as a heat sink, and also blocks off oxygen. There was a major plutonium-initiated fire at the Rocky Flats Plant near Boulder, Colorado in 1969.^[23] To avoid these problems, special precautions are necessary to store or handle plutonium in any form; generally a dry inert atmosphere is required.^[24] Plutonium hydride is a hydride of plutonium that can form on metallic plutonium when exposed to air. ... A pyrophoric substance is a substance that ignites spontaneously, that is, its autoignition temperature is below room temperature. ... This article is about the substance or device. ... The Rocky Flats Plant was a weapons production facility of the Atomic Energy Commission (AEC) that operated from 1952 to 1988. ... Boulder is a Home Rule Municipality that is the county seat and most populous city of Boulder County, Colorado, in the United States. ... Official language(s) English Demonym Coloradan Capital Denver Largest city Denver Largest metro area Denver-Aurora Metro Area Area  Ranked 8th in the US  - Total 104,185 sq mi (269,837 km²)  - Width 280 miles (451 km)  - Length 380 miles (612 km)  - % water 0. ... In English, to be inert is to be in a state of doing little or nothing. ...

See also

• Nuclear engineering
• Nuclear fuel cycle
• Nuclear physics
• Nuclear reactor
• Plutonium in the environment

Nuclear engineering is the practical application of the breakdown of atomic nuclei and/or other sub-atomic physics, based on the principles of nuclear physics. ... The nuclear fuel cycle, also called nuclear fuel chain, is the progression of nuclear fuel through a series of differing stages. ... This box:      Nuclear physics is the branch of physics concerned with the nucleus of the atom. ... Core of a small nuclear reactor used for research. ... To meet Wikipedias quality standards, this article may require cleanup. ...

References

Glenn Theodore Seaborg (April 19, 1912 – February 25, 1999) won the 1951 Nobel Prize in Chemistry for discoveries in the chemistry of the transuranium elements,[1] contributed to the discovery and isolation of ten elements, developed the actinide concept and was the first to propose the actinide series which led... Siegfried S. Hecker while director of Los Alamos National Laboratory. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 157th day of the year (158th in leap years) in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 46th day of the year in the Gregorian calendar. ... This article is about the nuclear weapon used in World War II. For other uses, see Fat Man (disambiguation). ... Harry K. Daghlian, Jr. ... A sketch used by doctors to determine the amount of radiation to which each person in the room had been exposed during the excursion. ... For the band, see 1997 (band). ... is the 163rd day of the year (164th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 167th day of the year (168th in leap years) in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 157th day of the year (158th in leap years) in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 157th day of the year (158th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 167th day of the year (168th in leap years) in the Gregorian calendar. ...

External links

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Plutonium

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• "A Perspective on the Dangers of Plutonium" by Lawrence Livermore National Laboratory
• Collection of articles on plutonium at the Canadian Coalition for Nuclear Responsibility
• The Myth of Plutonium Toxicity
• Criticality Accidents Report Issued
• Nuclear Weapons: Disposal Options for Surplus Weapons-Usable Plutonium
• Unraveling the Phase Diagram of Plutonium **Dead Link**
• Physical, Nuclear, and Chemical, Properties of Plutonium from IEER
• Los Alamos National Laboratory — Plutonium
• It's Elemental — Plutonium
• DOE Plutonium fact sheet (PDF)
• End of the Plutonium Age, D. Samuels, Discover Magazine, vol. 26, no. 11 (November, 2005).
• WebElements.com — Plutonium
• EnvironmentalChemistry.com — Plutonium (JavaScript required)
• Federation of American Scientists — Plutonium production
• nuclearweaponarchive.org — Plutonium Manufacture and Fabrication
• Ambient pressure phase diagram of plutonium — A unified theory for α-Pu and δ-Pu, P. Söderlind, Europhys. Lett., 55 (4), p. 525 (2001).
• Nuclear Files.org Information regarding world plutonium inventories
• "Challenges in Plutonium Science" — Special issue of Los Alamos Science from 2000 dedicated to scientific work on plutonium.
• NLM Hazardous Substances Databank – Plutonium, Radioactive
• Plutonium: A History of the World's Most Dangerous Element
• Annotated bibliography on plutonium from the Alsos Digital Library.