"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. Neptunium (nɛpˈtjuːniəm is a Chemical element with the symbol Np and Atomic number 93 Americium (ˌæməˈrɪsiəm is a Synthetic element that has the symbol Am and Atomic number 95 Samarium (səˈmɛəriəm is a Chemical element with the symbol Sm and Atomic number 62 This is a typical display of the periodic table of the elements and contains the symbol and Atomic number of each element Wikipedia talkFeatured lists for an explanation of this and other inclusion tags below -->This is a list of Chemical elements, sorted by name Wikipedia talkFeatured lists for an explanation of this and other inclusion tags below -->This is a list of chemical elements by symbol, including the A table of Chemical elements ordered by Atomic number and color coded according to type of element In Chemistry a group, also known as a family, is a vertical column in the Periodic table of the Chemical elements There are 18 groups in History of the actinoid series From the earlier known chemical properties of actinium (89 up to uranium (92 indicating a relation to the Transition metals it was generally In Chemistry a group, also known as a family, is a vertical column in the Periodic table of the Chemical elements There are 18 groups in 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 The respective highest-energy electrons in each element in a block belong to the same Atomic Occurrence Scandium yttrium and the Lanthanides (except promethium tend to occur together in the Earth's crust and are relatively abundant compared with most D-block 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 the elements consists of those elements (sometimes referred to as the inner transition elements) for which in the The atomic mass (ma is the Mass of an atom most often expressed in unified atomic mass units The atomic mass may be considered to be the total mass To help compare different orders of magnitude, the following list describes various Mass levels between 10&minus36&thinsp kg and 1053&thinspkg In Atomic physics and Quantum chemistry, electron configuration is the arrangement of Electrons in an Atom, Molecule, or other Radon (ˈreɪdɒn is the Chemical element that has the symbol Rn and Atomic number 86 The electron is a fundamental Subatomic particle that was identified and assigned the negative charge in 1897 by J An electron shell may be crudely thought of as an Orbit followed by Electrons around an Atom nucleus. 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 A solid' object is in the States of matter characterized by resistance to Deformation and changes of Volume. The density of a material is defined as its Mass per unit Volume: \rho = \frac{m}{V} Different materials usually have different Room temperature (also referred to as ambient temperature) is a common term to denote a certain Temperature within enclosed space at which humans are accustomed 816  g·cm−3
Liquid density at m.p.	16. The density of a material is defined as its Mass per unit Volume: \rho = \frac{m}{V} Different materials usually have different The melting point of a solid is the temperature range at which it changes state from solid to Liquid. 63  g·cm−3
Melting point	912. The melting point of a solid is the temperature range at which it changes state from solid to Liquid. 5 K (639. The kelvin (symbol K) is a unit increment of Temperature and is one of the seven SI base units The Kelvin scale is a thermodynamic 4 °C, 1182. The Celsius Temperature scale was previously known as the centigrade scale. 9 °F)
Boiling point	3505 K (3228 °C, 5842 °F)
Heat of fusion	2. Fahrenheit is a temperature scale named after Daniel Gabriel Fahrenheit (1686–1736 a German Physicist who proposed it in 1724 The boiling point of a liquid is the temperature at which the Vapor pressure of the liquid equals the environmental pressure surrounding the liquid The kelvin (symbol K) is a unit increment of Temperature and is one of the seven SI base units The Kelvin scale is a thermodynamic The Celsius Temperature scale was previously known as the centigrade scale. Fahrenheit is a temperature scale named after Daniel Gabriel Fahrenheit (1686–1736 a German Physicist who proposed it in 1724 The standard Enthalpy of fusion (symbol \Delta{}H_{fus} also known as the heat of fusion or specific melting heat, is the amount of 82  kJ·mol−1
Heat of vaporization	333. The joule per mole (symbol J·mol-1 is an SI derived unit of energy per amount of material The enthalpy of vaporization, (symbol \Delta{}_{v}H also known as the heat of vaporization or heat of evaporation, is the Energy required 5  kJ·mol−1
Specific heat capacity	(25 °C) 35. The joule per mole (symbol J·mol-1 is an SI derived unit of energy per amount of material Specific heat capacity, also known simply as specific heat, is the measure of the heat energy required to increase the Temperature of a unit quantity 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. Vapor pressure (also known as equilibrium vapor pressure or saturation vapor pressure) is the Pressure of a Vapor in equilibrium 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. " Electronegativity " is the opposite of " Electropositivity," which describes an element's ability to donate electrons 28 (Pauling scale)
Ionization energies	1st: 584. The ionization potential, ionization energy or EI of an Atom or Molecule is the Energy required to remove an Electron 7 kJ/mol
Atomic radius	175  pm
Miscellaneous
Magnetic ordering	no data
Electrical resistivity	(0 °C) 1. The joule per mole (symbol J·mol-1 is an SI derived unit of energy per amount of material Atomic radius, and more generally the size of an atom, is not a precisely defined Physical quantity, nor is it constant in all circumstances A picometre ( American spelling: picometer, symbol pm) is a unit of Length in the Metric system, equal to one trillionth In Physics, magnetism is one of the Phenomena by which Materials exert attractive or repulsive Forces on other Materials. Electrical resistivity (also known as specific electrical resistance) is a measure of how strongly a material opposes the flow of Electric current. 460 µΩ·m
Thermal conductivity	(300 K) 6. In Physics, thermal conductivity, k is the property of a material that indicates its ability to conduct Heat. 74  W·m−1·K−1
Thermal expansion	(25 °C) 46. When the Temperature of a substance changes the energy that is stored in the Intermolecular bonds between atoms changes 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. Sound is a vibration that travels through an elastic medium as a Wave. In Solid mechanics, Young's modulus (E is a measure of the Stiffness of an isotropic elastic material In Materials science, shear modulus or modulus of rigidity, denoted by G, or sometimes S or μ, is defined as the ratio of Shear Poisson's ratio ( ν) named after Simeon Poisson, is the ratio of the relative contraction strain, or transverse strain (normal to 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. CAS registry numbers are unique numerical identifiers for Chemical compounds Polymers biological sequences mixtures and Alloys They are also referred to Plutonium ( Pu) has no stable isotopes A standard atomic mass cannot be given Isotopes (Greek isos = "equal" tópos = "site place" are any of the different types of atoms ( Nuclides In Chemistry, natural abundance (NA refers to the abundance Isotopes of a Chemical element as naturally found on a planet Half-Life (computer-game page here It's already listed in the disambiguation page Radioactive decay is the process in which an unstable Atomic nucleus loses energy by emitting ionizing particles and Radiation. The decay energy is the Energy released by a Nuclear decay. The energy difference of the Reactants is often written as Q: where Q In Nuclear physics, a decay product, also known as a daughter product, daughter isotope or daughter nuclide, is a 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 To help compare Orders of magnitude of different times this page lists times between 109 Seconds (a gigasecond) and 1010 seconds (31 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 Alpha decay is a type of radioactive decay in which an Atomic nucleus emits an Alpha particle (two protons and two neutrons bound together into a particle 5 234U 239Pu syn 2.41×104 y SF - - α 5. Uranium (jʊˈreɪniəm is a silvery-gray Metallic Chemical element in the 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 To help compare Orders of magnitude of different times this page lists times between 32 000 Years and 320 000 years (1012 Seconds mdasha terasecond 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 Alpha decay is a type of radioactive decay in which an Atomic nucleus emits an Alpha particle (two protons and two neutrons bound together into a particle 245 235U 240Pu syn 6.5×103 y SF - - α 5. Uranium (jʊˈreɪniəm is a silvery-gray Metallic Chemical element in the 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 To help compare Orders of magnitude of different times this page lists times between 32 000 Years and 320 000 years (1012 Seconds mdasha terasecond 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 In Nuclear physics, beta decay is a type of Radioactive decay in which a Beta particle (an Electron or a Positron) is emitted 256 236U 241Pu syn 14 y β− . Uranium (jʊˈreɪniəm is a silvery-gray Metallic Chemical element in the 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 To help compare Orders of magnitude of different times this page lists times between 106 seconds and 107 seconds (approximately 11 In Nuclear physics, beta decay is a type of Radioactive decay in which a Beta particle (an Electron or a Positron) is emitted 02078 241Am SF - - 242Pu syn 3.73×105 y SF - - α 4. Americium (ˌæməˈrɪsiəm is a Synthetic element that has the symbol Am and Atomic number 95 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 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 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 984 238U 244Pu trace 8.08×107 y α 4. Uranium (jʊˈreɪniəm is a silvery-gray Metallic Chemical element in the A trace radioisotope is a Radioisotope that occurs naturally in trace amounts (i To help compare Orders of magnitude of different times this page lists times between 1015 seconds (a petasecond) and 1016 seconds (32 million years and Alpha decay is a type of radioactive decay in which an Atomic nucleus emits an Alpha particle (two protons and two neutrons bound together into a particle 666 240U SF - -
References

Plutonium (pronounced /pluːˈtoʊniəm/) is a rare radioactive, metallic and toxic chemical element. Uranium (jʊˈreɪniəm is a silvery-gray Metallic Chemical element in the 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 Recommended values for many properties of the elements together with various references are collected on these data pages Radioactive decay is the process in which an unstable Atomic nucleus loses energy by emitting ionizing particles and Radiation. The M acro E xpansion T emplate A ttribute L anguage complements TAL, providing macros which allow the reuse of code across Toxicity is the degree to which a substance is able to damage an exposed organism A chemical element is a type of Atom that is distinguished by its Atomic number; that is by the number of Protons in its nucleus. It has the symbol Pu and the atomic number 94. See also List of elements by atomic number In Chemistry and Physics, the atomic number (also known as the proton It is a fissile element used in most modern nuclear weapons. In Nuclear engineering, a fissile material is one that is capable of sustaining a Chain reaction of Nuclear fission. A nuclear weapon is an explosive device that derives its destructive force from Nuclear reactions either fission or a combination of fission and fusion. The most significant isotope of plutonium is ²³⁹Pu, with a half-life of 24,100 years. Isotopes (Greek isos = "equal" tópos = "site place" are any of the different types of atoms ( Nuclides Half-Life (computer-game page here It's already listed in the disambiguation page It can be made from natural uranium. Uranium (jʊˈreɪniəm is a silvery-gray Metallic Chemical element in the 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. In Physics a nucleon is a collective name for two Baryons the Neutron and the Proton. In Geology, a crust is the outermost solid shell of a planet or moon ^[1]

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. Allotropy (Gr allos, other and tropos, manner is a behavior exhibited by certain Chemical elements these elements can exist in two or more different 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). An alloy is a Solid solution or Homogeneous mixture of two or more elements, at least one of which is a Metal, which itself has Gallium (ˈgæliəm is a Chemical element that has the symbol Ga and Atomic number 31 ^[3] Plutonium is silvery in pure form, but has a yellow tarnish when oxidized. Redox (shorthand for reduction-oxidation reaction describes all Chemical reactions in which atoms have their Oxidation number ( Oxidation state 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. Annealing, in Metallurgy and Materials science, is a Heat treatment wherein a material is altered causing changes in its properties such as strength In general, the precise aging properties of plutonium are very complex and poorly understood, greatly complicating efforts to predict future reliability of weapons components.

The heat given off by alpha particle emission makes plutonium warm to the touch in reasonable quantities. Alpha decay is a type of radioactive decay in which an Atomic nucleus emits an Alpha particle (two protons and two neutrons bound together into a particle It displays five ionic oxidation states in aqueous solution:

• 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⁺. In Chemistry, the oxidation state is an indicator of the degree of Oxidation of an Atom in a Chemical compound. 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. In Nuclear engineering, a fissile material is one that is capable of sustaining a Chain reaction of Nuclear fission. A nuclear weapon is an explosive device that derives its destructive force from Nuclear reactions either fission or a combination of fission and fusion. 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. A critical mass is the smallest amount of Fissile material needed for a sustained Nuclear chain reaction. Nuclear weapon designs are physical chemical and engineering arrangements that cause the physics package of a nuclear weapon to detonate A neutron reflector is any material that reflects Neutrons Usually this term refers to the elastic scattering rather than to a Specular reflection. 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. The World War II Manhattan Project developed the first Nuclear weapon (atomic bomb "Fat Man" is the codename for the Atomic bomb that was detonated over Nagasaki, Japan, by the United States on August 9 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. "Fat Man" is the codename for the Atomic bomb that was detonated over Nagasaki, Japan, by the United States on August 9 (See also nuclear weapon design. Nuclear weapon designs are physical chemical and engineering arrangements that cause the physics package of a nuclear weapon to detonate )

The isotope plutonium-238 (²³⁸Pu) has a half-life of 88 years and emits a large amount of thermal energy as it decays. Plutonium 238, is a Radioactive isotope of Plutonium with a half-life of 87 Thermal energy is the sum of the sensible energy and latent energy. Being an alpha emitter, it combines high energy radiation with low penetration (thereby requiring minimal shielding). Alpha particles (named after and denoted by the first letter in the Greek alphabet, α consist of two Protons and two Neutrons bound together into a 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. A radioisotope thermoelectric generator ( RTG, RITEG) is an Electrical generator which obtains its power from Radioactive decay. Cassini–Huygens is a joint NASA / ESA / ASI Robotic spacecraft mission currently studying the planet Saturn and its New Horizons is a Robotic spacecraft mission by NASA currently underway Seismology (from Greek grc σεισμός seismos, "earthquake" and grc -λογία -logia) is the scientific study of Earthquakes

²³⁸Pu has been used successfully to power artificial heart pacemakers, to reduce the risk of repeated surgery. For other uses see Pacemaker (disambiguation A pacemaker (or artificial pacemaker, so as not to be confused with the heart's natural pacemaker 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. Lithium (ˈlɪθiəm is a Chemical element with the symbol Li and Atomic number 3 A primary cell is any kind of Electrochemical cell in which the electrochemical reaction of interest is not reversible so used in Disposable

History

Glenn Seaborg at the Geiger Counter, 301 Gilman Hall, Berkeley, California, where he discovered plutonium. Glenn Theodore Seaborg ( Glenn Teodor Sjöberg) ( April 19, 1912 &ndash February 25, 1999) won the 1951 Nobel Prize in Chemistry Gilman Hall is a building on the campus of the University of California Berkeley.

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. Neptunium (nɛpˈtjuːniəm is a Chemical element with the symbol Np and Atomic number 93 Uranium-238 (U-238 is the most common isotope of Uranium found in nature Edwin Mattison McMillan ( September 18, 1907 &ndash September 7, 1991) was an American physicist and Nobel laureate credited with being Philip Hauge Abelson ( April 27, 1913 – August 1, 2004) was an American Physicist, editor of scientific literature and The Ernest Orlando Lawrence Berkeley National Laboratory ( LBNL) is a U The University of California Berkeley (also referred to as Cal, Berkeley and UC Berkeley) is a major research university located in Berkeley Born near Zurich, Switzerland in 1901 and educated at the ETH there Bretscher gained a PhD degree in organic chemistry at Edinburgh in 1926 Norman Feather ( 16 November 1904 – 14 August 1978) FRS 1945 FRSE 1946 was a British physicist The Cavendish Laboratory is the University of Cambridge 's Department of Physics, and is part of the university's School of Physical Sciences The University of Cambridge (often Cambridge University) located in Cambridge, England, is the second-oldest university in the Tube Alloys was the code-name for the British Nuclear weapon directorate during World War II, when the very possibility of nuclear weapons was kept at such a high Coincidentally both teams proposed the same names to follow on from uranium, following the sequence of the outer planets.

First isolation

Plutonium was first produced and isolated on December 14, 1940 by Dr. Events 1287 - St Lucia's flood: The Zuider Zee sea wall in the Netherlands collapses killing over 50000 people Year 1940 ( MCMXL) was a Leap year starting on Monday (link will display the full 1940 calendar of the Gregorian calendar. Glenn T. Seaborg, Edwin M. McMillan, J. W. Kennedy, Z. Glenn Theodore Seaborg ( Glenn Teodor Sjöberg) ( April 19, 1912 &ndash February 25, 1999) won the 1951 Nobel Prize in Chemistry Edwin Mattison McMillan ( September 18, 1907 &ndash September 7, 1991) was an American physicist and Nobel laureate credited with being Joseph William Kennedy ( May 30, 1916 &ndash May 5, 1957) was an American Scientist credited with being a co-discoverer M. Tatom, and A. C. Wahl by deuteron bombardment of uranium in the 60-inch (1,500 mm) cyclotron at Berkeley. Arthur Wahl ( September 8, 1917 &ndash April 2006 was an American Chemist who as a PhD graduate student under Dr Deuterium, also called heavy hydrogen, is a Stable isotope of Hydrogen with a Natural abundance in the Oceans of Earth The discovery was kept secret due to the war. World War II, or the Second World War, (often abbreviated WWII) was a global military conflict which involved a majority of the world's nations, including 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"). Neptunium (nɛpˈtjuːniəm is a Chemical element with the symbol Np and Atomic number 93 Uranium (jʊˈreɪniəm is a silvery-gray Metallic Chemical element in the 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. A chemical 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 of the chemical elements is a tabular method of displaying the Chemical elements Although precursors to this table exist its invention is ^[9]

Chemists at the University of Chicago began to study the newly manufactured radioactive element. The University of Chicago is a Private university located principally in the Hyde Park neighborhood of Chicago. 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. The George Herbert Jones Laboratory, at 5747 S Ellis Avenue Chicago Illinois, is a facility building of the University of Chicago. 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. A National Historic Landmark (NHL is a Building, site, Structure, Object, or District, that is officially recognized by the ^[10]

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. The World War II Manhattan Project developed the first Nuclear weapon (atomic bomb The X-10 Graphite Reactor at Oak Ridge National Laboratory in Oak Ridge Tennessee, formerly known as the Clinton Pile and X-10 Pile, was the Oak Ridge is an incorporated City in Anderson and Roane Counties in East Tennessee, USA, about 25 miles northwest of Tennessee ( is a state located in the Southern United States. Oak Ridge National Laboratory ( ORNL) is a multiprogram science and technology National laboratory managed for the United States Department of Energy by 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. This article is a subarticle of Nuclear power. A nuclear reactor is a device in which Nuclear chain reactions are initiated controlled The Hanford Site is a decommissioned nuclear production complex on the Columbia River in south-central Washington operated by the United States government Richland is a city in Benton County in the southeastern part of the U Trinity was the first test of technology for a Nuclear weapon. Plutonium was also used in the "Fat Man" bomb dropped on Nagasaki, Japan in August 1945. "Fat Man" is the codename for the Atomic bomb that was detonated over Nagasaki, Japan, by the United States on August 9 ( is the Capital and the largest city of Nagasaki Prefecture in Japan. The "Little Boy" bomb dropped on Hiroshima used uranium-235, not plutonium. Little Boy was the Codename of the Atomic bomb, developed via the "Manhattan Project" which was dropped on Hiroshima, on August 6 1945 by the The Japanese city of ( is the capital of Hiroshima Prefecture, and the largest city in the Chūgoku region of western Honshū, the largest of Japan 's Uranium-235 is an isotope of uranium that differs from the element's other common isotope Uranium-238, by its ability to cause a rapidly expanding fission

Large stockpiles of "weapons-grade" plutonium were built up by both the Soviet Union and the United States during the Cold War. The Union of Soviet Socialist Republics (USSR was a constitutionally Socialist state that existed in Eurasia from 1922 to 1991 The United States of America —commonly referred to as the Cold War is the state of conflict tension and competition that existed between the United States and the Soviet Union (USSR and their respective allies from the 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. The Hanford Site is a decommissioned nuclear production complex on the Columbia River in south-central Washington operated by the United States government The Savannah River Site (SRS is a nuclear materials processing center in the United States state of South Carolina, located on land in Aiken Allendale and Barwnell ^[14] Since the end of the Cold War, these stockpiles have become a focus of nuclear proliferation concerns. Nuclear proliferation is a term now used to describe the spread of Nuclear weapons, fissile material and weapons-applicable nuclear technology and information to nations 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. The United States Department of Energy ( DOE) is a Cabinet -level department of the United States government responsible for energy policy 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 Enriched uranium is a kind of Uranium in which the percent composition of Uranium-235 has been increased through the process of Isotope separation. Mixed oxide, or MOX fuel, is a blend of oxides of Plutonium and Natural uranium, Reprocessed uranium, or Depleted uranium which behaves

Hanford Site plutonium production reactors along the Columbia River during the Manhattan Project. The Columbia River (known as The World War II Manhattan Project developed the first Nuclear weapon (atomic bomb

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. 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 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. The World War II Manhattan Project developed the first Nuclear weapon (atomic bomb 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. 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 implications ^[15]

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. The Hippocratic Oath is an oath traditionally taken by physicians pertaining to the ethical practice of medicine "^[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]

Occurrence

While almost all plutonium is manufactured synthetically, extremely tiny trace amounts are found naturally in uranium ores. Uranium (jʊˈreɪniəm is a silvery-gray Metallic Chemical element in the 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. Neutron capture is a kind of Nuclear reaction in which an Atomic nucleus collides with one or more Neutrons and they merge to form a heavier nucleus In Nuclear physics, beta decay is a type of Radioactive decay in which a Beta particle (an Electron or a Positron) is emitted Neptunium (nɛpˈtjuːniəm is a Chemical element with the symbol Np and Atomic number 93 This is also the process used to manufacture ²³⁹Pu in nuclear reactors. This article is a subarticle of Nuclear power. A nuclear reactor is a device in which Nuclear chain reactions are initiated controlled Some traces of ²⁴⁴Pu remain from the birth of the solar system from the waste of supernovae, because its half-life of 80 million years is fairly long.

A relatively high concentration of plutonium was discovered at the natural nuclear fission reactor in Oklo, Gabon in 1972. A natural nuclear fission reactor is a Uranium deposit where analysis of Isotope Ratios has shown that self-sustaining Nuclear chain reactions Oklo is a region near the town of Franceville, in the Haut-Ogooué province of the Central African state of Gabon. Gabon (gəˈbɒn or /gaˈbõ/ in French) is a country in west central Africa sharing borders with Equatorial Guinea, Cameroon, Republic Since 1945, approximately 7700 kg has been released onto Earth through nuclear explosions. EARTH was a short-lived Japanese vocal trio which released 6 singles and 1 album between 2000 and 2001 The energy released from a nuclear weapon detonated in the Troposphere can be divided into four basic categories Blast &mdash40-50% of total energy

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. In nuclear and Particle physics, the concept of a cross section is used to express the likelihood of interaction between particles A barn (symbol b) is a unit of Area. While the barn is not an SI unit it is accepted (although discouraged for use with the SI 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.

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. Plutonium-239 is an Isotope of Plutonium. Plutonium-239 is the primary Fissile isotope used for the production of Nuclear weapons although In Nuclear engineering, a fissile material is one that is capable of sustaining a Chain reaction of Nuclear fission. A nuclear weapon is an explosive device that derives its destructive force from Nuclear reactions either fission or a combination of fission and fusion. This article is a subarticle of Nuclear power. A nuclear reactor is a device in which Nuclear chain reactions are initiated controlled The other fissile materials are uranium-235 and uranium-233. Uranium-235 is an isotope of uranium that differs from the element's other common isotope Uranium-238, by its ability to cause a rapidly expanding fission Uranium-233 is a Fissile artificial isotope of Uranium, which has been used in a few Nuclear reactors and has been proposed for much wider use as a Plutonium-239 is virtually nonexistent in nature. It is made by bombarding uranium-238 with neutrons in a nuclear reactor. Uranium-238 (U-238 is the most common isotope of Uranium found in nature 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. This article is a discussion of neutrons in general For the specific case of a neutron found outside the nucleus see Free neutron.

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.

Pu-238

Main article: Plutonium-238

There are small amounts of Pu-238 in the plutonium of usual plutonium-producing reactors. Plutonium 238, is a Radioactive isotope of Plutonium with a half-life of 87 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. Neptunium (nɛpˈtjuːniəm is a Chemical element with the symbol Np and Atomic number 93 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.

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. Oxygen (from the Greek roots ὀξύς (oxys (acid literally "sharp" from the taste of acids and -γενής (-genēs (producer literally begetteris the Plutonium(IV oxide is the Chemical compound with the formula PuO2 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. Abundance Owing to their high Reactivity, the halogens are found in the environment only in compounds or as Ions Halide ions and oxoanions 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. Carbon (kɑɹbən is a Chemical element with the symbol C and its Atomic number is 6 Nitrogen (ˈnaɪtɹəʤɪn is a Chemical element that has the symbol N and Atomic number 7 and Atomic weight 14 Silicon (ˈsɪlɪkən or /ˈsɪlɪkɒn/ silicium is the Chemical element that has the symbol Si and Atomic number 14

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. See also Plutonium, Allotrope Even at ambient pressure plutonium occurs in a variety of Allotropes These allotropes differ widely in crystal structure Allotropy (Gr allos, other and tropos, manner is a behavior exhibited by certain Chemical elements these elements can exist in two or more different These allotropes differ widely in crystal structure and density; the α and δ allotropes differ in density by more than 25% at constant pressure.

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. In Thermodynamics, phase transition or phase change is the transformation of a thermodynamic system from one phase to another

In weapons applications, plutonium is often alloyed with another metal (e. An alloy is a Solid solution or Homogeneous mixture of two or more elements, at least one of which is a Metal, which itself has g. , delta phase with a small percentage of gallium) to increase phase stability and thereby enhance workability and ease of handling. Gallium (ˈgæliəm is a Chemical element that has the symbol Ga and Atomic number 31 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. For the music album by Converter see Shock Front For the 1977 horror film see Shock Waves A shock wave (also called A critical mass is the smallest amount of Fissile material needed for a sustained Nuclear chain reaction.

Isotopes

Main article: Isotopes of plutonium

Twenty-one plutonium radioisotopes have been characterized. Plutonium ( Pu) has no stable isotopes A standard atomic mass cannot be given A radionuclide is an Atom with an unstable nucleus, which is a nucleus characterized by excess energy which is available to be imparted either to a newly-created The most stable are Pu-244, with a half-life of 80. Half-Life (computer-game page here It's already listed in the disambiguation page 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. Radioactive decay is the process in which an unstable Atomic nucleus loses energy by emitting ionizing particles and Radiation. This element also has eight meta states, though none are very stable (all have half-lives less than one second). A nuclear isomer is a Metastable state of an Atomic nucleus caused by the excitation of one or more of its Nucleons A nuclear isomer occupies

The isotopes of plutonium range in atomic weight from 228. The atomic mass (ma is the Mass of an atom most often expressed in unified atomic mass units The atomic mass may be considered to be the total mass 0387 u (Pu-228) to 247. The unified atomic mass unit ( u) or Dalton ( Da) or sometimes universal mass unit, is an unit of Mass used to express 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. Radioactive decay is the process in which an unstable Atomic nucleus loses energy by emitting ionizing particles and Radiation. 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 Alpha decay is a type of radioactive decay in which an Atomic nucleus emits an Alpha particle (two protons and two neutrons bound together into a particle In Nuclear physics, beta decay is a type of Radioactive decay in which a Beta particle (an Electron or a Positron) is emitted 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. In Nuclear physics, a decay product, also known as a daughter product, daughter isotope or daughter nuclide, is a Nuclide Americium (ˌæməˈrɪsiəm is a Synthetic element that has the symbol Am and Atomic number 95

A pellet of plutonium-238, glowing due to blackbody radiation, used for radioisotope thermoelectric generators. The Electromagnetic radiation emitted by a Black body. You may also be looking for Incandescence, the radiation from a body A radioisotope thermoelectric generator ( RTG, RITEG) is an Electrical generator which obtains its power from Radioactive decay.

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. A radioisotope thermoelectric generator ( RTG, RITEG) is an Electrical generator which obtains its power from Radioactive decay. 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. A chain reaction is a sequence of Reactions where a reactive product or by-product causes additional reactions to take place 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. 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. The "Thin Man" (formally Mark 2) nuclear bomb was a proposed Plutonium gun-type nuclear bomb which the United States was 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.

Precautions

Toxicity

Glowing hot bits of plutonium in a box, which have been set alight due to plutonium's pyrophoric nature. Incandescence is the emission of Light (visible Electromagnetic radiation) from a hot body due to its temperature A pyrophoric substance will ignite spontaneously that is its Autoignition temperature is below Room temperature.

Isotopes and compounds of plutonium are toxic due to its radioactivity^[19] 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. Toxicity is the degree to which a substance is able to damage an exposed organism ^[20][21] 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. ^[22] (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. The biological half-life of a substance is the time it takes for a substance (drug radioactive nuclide or other to lose half of its pharmacologic physiologic or radiologic activity ^[23] From a purely chemical standpoint, it is about as poisonous as lead and other heavy metals. Characteristics Lead has a dull luster and is a dense, Ductile, very soft highly Plutonium has a metallic taste. ^[24]

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. Alpha particles (named after and denoted by the first letter in the Greek alphabet, α consist of two Protons and two Neutrons bound together into a 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. In Biology, the skeleton is a strong and often a rigid framework that supports the body of an animal holding it upright and giving it shape and strength (Also skeletal The liver is a vital organ in the human body and is present in Vertebrates and some other animals 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. 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. Ricin (ˈraɪ sɨn 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 Botulinum toxin is a Neurotoxin Protein produced by the Bacterium Clostridium botulinum. Tetanus is a medical condition that is characterized by a prolonged contraction of Skeletal muscle fibres Nerve agents (also being referred to as nerve gases, though these chemicals are liquid at room temperature are a class of Phosphorus -containing organic chemicals The Genus Amanita contains about 600 Species of Agarics including some of the most Toxic known mushrooms found worldwide 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. Radiation poisoning, also called " radiation sickness " or a " creeping dose " is a form of damage to organ tissue due to excessive exposure to ^[21]

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. Radium (ˈreɪdiəm is a radioactive Chemical element which has the symbol Ra and Atomic number 88 Carbon-14, 14C, or radiocarbon, is a Radioactive isotope of Carbon discovered on February 27, 1940, by Cold War is the state of conflict tension and competition that existed between the United States and the Soviet Union (USSR and their respective allies from the 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). Mixed oxide, or MOX fuel, is a blend of oxides of Plutonium and Natural uranium, Reprocessed uranium, or Depleted uranium which behaves 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. ^[25]

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. A critical mass is the smallest amount of Fissile material needed for a sustained Nuclear chain reaction. 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.

Criticality accidents have occurred in the past, some of them with lethal consequences. A criticality accident, sometimes referred to as an excursion or a power excursion, occurs when a Nuclear chain reaction accidentally occurs in Fissile 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. Los Alamos National Laboratory (LANL (previously known at various times as Site Y, Los Alamos Laboratory, and Los Alamos Scientific Laboratory) is a Events 1192 - Minamoto Yoritomo becomes Seii Tai Shōgun and the De facto ruler of Japan. Year 1945 ( MCMXLV) was a Common year starting on Monday (link will display the full calendar Harry K Daghlian Jr (1921 &ndash September 15, 1945) was a Physicist with the Manhattan Project who died from performing an accidental The Röntgen ( roentgen) equivalent in man or rem (symbol rem) 1 Sv) and died four weeks later. The sievert (symbol Sv is the SI derived unit of dose equivalent. 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. Louis Alexander Slotin (December 1 1910 – May 30 1946 was a Canadian Physicist and Chemist who took part in the Manhattan Project. The Demon core was the nickname given to a spherical subcritical mass of Plutonium that accidentally went critical on two separate instances These incidents were fictionalized in the 1989 film Fat Man and Little Boy. Fat Man and Little Boy (aka Shadow Makers in the UK is a 1989 film that reenacts the Manhattan Project, the secret Allied 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. The Union of Soviet Socialist Republics (USSR was a constitutionally Socialist state that existed in Eurasia from 1922 to 1991 For a topic outline on this subject see List of basic Japan topics. (See List of nuclear accidents. This article covers notable accidents involving nuclear devices and radioactive materials ) The 1986 Chernobyl accident caused a minor release of plutonium.

Flammability

Metallic plutonium is also a fire hazard, especially if the material is finely divided. The Chernobyl disaster was a nuclear reactor accident in the Chernobyl Nuclear Power Plant in the Soviet Union. Plutonium in the environment is an article which is part of the Actinides in the environment series 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 hydride is a Hydride of Plutonium that can form on metallic plutonium when exposed to air A pyrophoric substance will ignite spontaneously that is its Autoignition temperature is below 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. A heat sink (or heatsink) is an environment or object that absorbs and dissipates heat from another object using Thermal contact (either direct or radiant There was a major plutonium-initiated fire at the Rocky Flats Plant near Boulder, Colorado in 1969. The Rocky Flats Plant was a United States Nuclear weapons production facility near Denver Colorado that operated from 1952 to 1992 Boulder is a Home Rule Municipality that is the County seat and most populous city of Boulder County, Colorado, in the United States The State of Colorado ( or chiefly by nonresidents) is a state located in the Rocky Mountain region of the United States of America. ^[26] To avoid these problems, special precautions are necessary to store or handle plutonium in any form; generally a dry inert atmosphere is required. In English to be inert is to be in a state of doing little or nothing ^[27]

See also

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

References

External links

• "A Perspective on the Dangers of Plutonium" by Lawrence Livermore National Laboratory [no longer online, but still available from the Internet Archive ]
• 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.