84 bismuth ← polonium → astatine Te ↑ Po ↓ Uuh Periodic Table - Extended Periodic Table
General
Name, Symbol, Number	polonium, Po, 84
Chemical series	metalloids
Group, Period, Block	16, 6, p
Appearance	silvery
Standard atomic weight	(209)  g·mol−1
Electron configuration	[Xe] 6s2 4f14 5d10 6p4
Electrons per shell	2, 8, 18, 32, 18, 6
Physical properties
Phase	solid
Density (near r.t.)	(alpha) 9. Bismuth (ˈbɪzməθ is a Chemical element that has the symbol Bi and Atomic number 83 Astatine (ˈæstətiːn is a Radioactive Chemical element with the symbol At and Atomic number 85 Tellurium (tɪˈlʊəriəm/ /tɛl- is a Chemical element that has the symbol Te and Atomic number 52 Ununhexium (ˌjuːnənˈhɛksiəm or /ˌʌnənˈhɛksiəm/ is the temporary name of a synthetic Superheavy element in the Periodic table that has the temporary 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 Metalloid is a term used in Chemistry when classifying the Chemical elements On the basis of their general physical and chemical properties nearly every 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 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 See also Gold chalcogenides Periodic table A period 6 element is one of the Chemical elements in the sixth row (or period) of the periodic table of the elements, including the Lanthanides See also Electron configuration 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 Xenon (ˈzɛnɒn or) is a Chemical element represented by the symbol Xe. 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 196  g·cm−3
Density (near r.t.)	(beta) 9. 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 398  g·cm−3
Melting point	527 K (254 °C, 489 °F)
Boiling point	1235 K (962 °C, 1764 °F)
Heat of fusion	ca. The melting point of a solid is the temperature range at which it changes state from solid to 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 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 13  kJ·mol−1
Heat of vaporization	102. 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 91  kJ·mol−1
Specific heat capacity	(25 °C) 26. 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 4  J·mol−1·K−1
Vapor pressure P(Pa) 1 10 100 1 k 10 k 100 k at T(K)       (846) 1003 1236
Atomic properties
Crystal structure	cubic
Oxidation states	4, 2 (amphoteric oxide)
Electronegativity	2. 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 0 (Pauling scale)
Ionization energies	1st: 812. The ionization potential, ionization energy or EI of an Atom or Molecule is the Energy required to remove an Electron 1 kJ/mol
Atomic radius	190  pm
Atomic radius (calc. 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 )	135  pm
Miscellaneous
Magnetic ordering	nonmagnetic
Electrical resistivity	(0 °C) (α) 0. 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. 40 µΩ·m
Thermal conductivity	(300 K)  ? 20  W·m−1·K−1
Thermal expansion	(25 °C) 23. In Physics, thermal conductivity, k is the property of a material that indicates its ability to conduct Heat. When the Temperature of a substance changes the energy that is stored in the Intermolecular bonds between atoms changes 5  µm·m−1·K−1
CAS registry number	7440-08-6
Selected isotopes
Main article: Isotopes of polonium iso NA half-life DM DE (MeV) DP 208Po syn 2. CAS registry numbers are unique numerical identifiers for Chemical compounds Polymers biological sequences mixtures and Alloys They are also referred to Polonium ( Po) has 33 known isotopes, all of which are radioactive. 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 898 y α 5. A year (from Old English gēr) is the time between two recurrences of an event related to the Orbit of the Earth around the Sun 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 215 204Pb ε, β+ 1. Characteristics Lead has a dull luster and is a dense, Ductile, very soft highly Electron capture (sometimes called inverse beta decay) is a Decay mode for Isotopes that will occur when there are too many Protons in the Positron emission is a type of Beta decay, sometimes referred to as " beta plus " (&beta+ 401 208Bi 209Po syn 103 y α 4. Bismuth (ˈbɪzməθ is a Chemical element that has the symbol Bi and Atomic number 83 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 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 979 205Pb ε, β+ 1. Characteristics Lead has a dull luster and is a dense, Ductile, very soft highly Electron capture (sometimes called inverse beta decay) is a Decay mode for Isotopes that will occur when there are too many Protons in the Positron emission is a type of Beta decay, sometimes referred to as " beta plus " (&beta+ 893 209Bi 210Po syn 138. Bismuth (ˈbɪzməθ is a Chemical element that has the symbol Bi and Atomic number 83 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 376 d α 5. A day (symbol d is a unit of Time equivalent to 24 Hours and the duration of a single Rotation of planet Earth with respect to the 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 407 206Pb
References

Polonium (pronounced /pəˈloʊniəm/) is a chemical element that has the symbol Po and atomic number 84. Characteristics Lead has a dull luster and is a dense, Ductile, very soft highly Recommended values for many properties of the elements together with various references are collected on these data pages 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. See also List of elements by atomic number In Chemistry and Physics, the atomic number (also known as the proton A rare and highly radioactive metalloid,^[1] polonium is chemically similar to tellurium and bismuth, and it occurs in uranium ores. Radioactive decay is the process in which an unstable Atomic nucleus loses energy by emitting ionizing particles and Radiation. Metalloid is a term used in Chemistry when classifying the Chemical elements On the basis of their general physical and chemical properties nearly every element Tellurium (tɪˈlʊəriəm/ /tɛl- is a Chemical element that has the symbol Te and Atomic number 52 Bismuth (ˈbɪzməθ is a Chemical element that has the symbol Bi and Atomic number 83 Uranium (jʊˈreɪniəm is a silvery-gray Metallic Chemical element in the An ore is a volume of rock containing components or Minerals in a mode of occurrence that renders it valuable for mining Polonium has been studied for possible use in heating spacecraft. A spacecraft is a Vehicle or machine designed for Spaceflight. It is unstable; all isotopes of polonium are radioactive. Polonium ( Po) has 33 known isotopes, all of which are radioactive.

Notable characteristics

Polonium is a radioactive element that exists in two metallic allotropes. The M acro E xpansion T emplate A ttribute L anguage complements TAL, providing macros which allow the reuse of code across Allotropy (Gr allos, other and tropos, manner is a behavior exhibited by certain Chemical elements these elements can exist in two or more different ^[2]

Isotopes

Main article: Isotopes of polonium

Polonium has 25 known isotopes, all of which are radioactive. Polonium ( Po) has 33 known isotopes, all of which are radioactive. Polonium ( Po) has 33 known isotopes, all of which are radioactive. Radioactive decay is the process in which an unstable Atomic nucleus loses energy by emitting ionizing particles and Radiation. They have atomic masses that range from 194u to 218u. 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 ²¹⁰Po (half-life 138. 376 days) is the most widely available. ²⁰⁹Po (half-life 103 years) and ²⁰⁸Po (half-life 2. 9 years) can be made through the alpha, proton, or deuteron bombardment of lead or bismuth in a cyclotron. Characteristics Lead has a dull luster and is a dense, Ductile, very soft highly Bismuth (ˈbɪzməθ is a Chemical element that has the symbol Bi and Atomic number 83 A cyclotron is a type of Particle accelerator. Cyclotrons accelerate Charged particles using a high- Frequency, alternating Voltage (potential

²¹⁰Po

²¹⁰Po is an alpha emitter that has a half-life of 138. 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 376 days; it decays directly to its daughter isotope ²⁰⁶Pb. In Nuclear physics, a decay product, also known as a daughter product, daughter isotope or daughter nuclide, is a Nuclide Characteristics Lead has a dull luster and is a dense, Ductile, very soft highly A milligram of ²¹⁰Po emits about as many alpha particles per second as 4. 5 grams of ²²⁶Ra. Radium (ˈreɪdiəm is a radioactive Chemical element which has the symbol Ra and Atomic number 88 A few curies (1 curie equals 37 gigabecquerels) of ²¹⁰Po emit a blue glow which is caused by excitation of surrounding air. A CURIE (short for Compact URI) is an abbreviated URI expressed in CURIE syntax and may be found in both XML and non-XML grammars The becquerel (symbol Bq) is the SI derived unit of radioactivity. Excitation is an elevation in energy level above an arbitrary baseline energy state A single gram of ²¹⁰Po generates 140 watts of power. ^[3] Because it emits many alpha particles, which are stopped within a very short distance in dense media and release their energy, ²¹⁰Po has been used as a lightweight heat source to power thermoelectric cells in artificial satellites; for instance, ²¹⁰Po heat source was also used in each of the Lunokhod rovers deployed on the surface of the Moon, to keep their internal components warm during the lunar nights. 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 A radioisotope thermoelectric generator ( RTG, RITEG) is an Electrical generator which obtains its power from Radioactive decay. This article is about artificial satellites For natural satellites also known as moons see Natural satellite. Lunokhod ( Russian Луноход "Moonwalker") 1 and 2 were a pair of by the Soviet robotic lunar rovers landed on the ^[4] Some anti-static brushes contain up to 500 microcuries of ²¹⁰Po as a source of charged particles for neutralizing static electricity in materials like photographic film. ^{[5] 210}Po was also used as a murder weapon in the Alexander Litvinenko poisoning

The majority of the time ²¹⁰Po decays by emission of an alpha particle only, not by emission of an alpha particle and a gamma ray. Alexander Litvinenko was a former officer of Russian Federal Security Service, who escaped prosecution in Russia and received a Political asylum in 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 Gamma rays (denoted as &gamma) are a form of Electromagnetic radiation or light emission of frequencies produced by sub-atomic particle interactions About one in 100,000 alpha emissions causes an excitation in the nucleus which then results in the emission of a gamma ray. ^[6] This low gamma ray production rate (and the short range of alpha particles) makes it difficult to find and identify this isotope. Rather than gamma ray spectroscopy, alpha spectroscopy is the best method of measuring this isotope.

Solid state form

The alpha form of solid polonium has a simple cubic crystal structure with an edge length of 3. The cubic crystal system (or isometric) is a Crystal system where the Unit cell is in the shape of a Cube. 352 Å.

The beta form of polonium is rhombohedral; it has been reported in the chemical literature, along with the alpha form, several times. In Crystallography, the rhombohedral (or trigonal) Crystal system is one of the seven lattice point groups named after the two-dimensional A picture of it is present on the web. ^[7]

Two papers report X-ray diffraction experiments on polonium metal. Diffraction is normally taken to refer to various phenomena which occur when a wave encounters an obstacle ^[8][9] The first report of the crystal structure of polonium was done using electron diffraction. Electron diffraction is a technique used to study matter by firing Electrons at a sample and observing the resulting Interference pattern ^[10]

Chemistry

The chemistry of polonium is similar to that of tellurium and bismuth. Tellurium (tɪˈlʊəriəm/ /tɛl- is a Chemical element that has the symbol Te and Atomic number 52 Bismuth (ˈbɪzməθ is a Chemical element that has the symbol Bi and Atomic number 83 Polonium dissolves readily in dilute acids, but is only slightly soluble in alkalis. In Computer science, ACID ( Atomicity Consistency Isolation Durability) is a set of properties that guarantee that Database transactions are Solubility is the characteristic Physical property referring to the ability of a given substance the Solute, to dissolve in a Solvent. In Chemistry, an alkali (from Arabic: Al-Qaly القلي القالي) is a basic, ionic salt of an Alkali metal The hydrogen compound PoH₂ is liquid at room temperature (M.P. -36. The melting point of a solid is the temperature range at which it changes state from solid to Liquid. 1°C to B.P. 35. The boiling point of a liquid is the temperature at which the Vapor pressure of the liquid equals the environmental pressure surrounding the liquid 3°C). Halides of the structure PoX₂, PoX₄ and PoX₆ are known. A halide is a Binary compound, of which one part is a Halogen Atom and the other part is an element or radical that is less The two oxides PoO₂ and PoO₃ are the products of oxidation of polonium. ^[11]

²¹⁰Po (in common with ²³⁸Pu) has the ability to become airborne with ease: if a sample is heated in air to 328 K (55°C, 131°F), 50% of it is vaporized in 45 hours, even though the melting point of polonium is 527 K (254°C, 489°F) and its boiling point is 1235 K (962°C, 1763°F). Plutonium 238, is a Radioactive isotope of Plutonium with a half-life of 87 Volatility in the context of Chemistry, Physics and Thermodynamics is a measure of the tendency of a substance to Vaporize. ^[12] More than one hypothesis exists for how polonium does this; one suggestion is that small clusters of polonium atoms are spalled off by the alpha decay. In general spallation is a process in which fragments of material ( Spall) are ejected from a body due to impact or stress

It has been reported that some microbes can methylate polonium by the action of methylcobalamin. A microorganism (also spelled micro organism or micro-organism and also called a microbe) is an Organism that is Microscopic (usually Methylation is a term used in the chemical sciences to denote the attachment or substitution of a methyl group on various substrates. Methylcobalamin is a cobalamin (MeB12 used in Peripheral neuropathy, Diabetic neuropathy etc ^[13][14]This is similar to the way in which mercury, selenium and tellurium are methylated in living things to create organometallic compounds. Mercury (ˈmɜrkjʊri also called quicksilver or hydrargyrum, is a Chemical element with the symbol Hg ( Latinized hydrargyrum Selenium (səˈliniəm is a Chemical element with the Atomic number 34 represented by the chemical symbol Se, an atomic mass of 78 Tellurium (tɪˈlʊəriəm/ /tɛl- is a Chemical element that has the symbol Te and Atomic number 52 Organometallic chemistry is the study of Chemical compounds containing bonds between Carbon and a Metal. As a result when considering the biochemistry of polonium one should consider the possibility that the polonium will follow the same biochemical pathways as selenium and tellurium.

The alpha form of solid polonium.

Compounds

History

Also tentatively called "Radium F", polonium was discovered by Marie Skłodowska-Curie and her husband Pierre Curie in 1898^[15] and was later named after Marie Curie's native land of Poland (Latin: Polonia), and not for the Hamlet character, Polonius. Pierre Curie (15 May 1859 &ndash 19 April 1906 was a French physicist, a pioneer in Crystallography, Magnetism, Piezoelectricity Poland (Polska officially the Republic of Poland Latin ( lingua Latīna, laˈtiːna is an Italic language, historically spoken in Latium and Ancient Rome. Hamlet is a Tragedy by William Shakespeare, believed to have been written between 1599 and 1601 Polonius is a character from William Shakespeare 's Hamlet. The character is best known for uttering the immortal words "To thine own self be true" ^[16][17] Poland at the time was under Russian, Prussian, and Austrian partition, and did not exist as an independent country. The Partitions of Poland or Partitions of the Polish Lithuanian Commonwealth took place in the second half of the 18th century and ended the existence of the It was Curie's hope that naming the element after her native land would publicize its lack of independence. Polonium may be the first element named to highlight a political controversy. ^[18]

This element was the first one discovered by the Curies while they were investigating the cause of pitchblende radioactivity. Radioactive decay is the process in which an unstable Atomic nucleus loses energy by emitting ionizing particles and Radiation. The pitchblende, after removal of the radioactive elements uranium and thorium, was more radioactive than both the uranium and thorium put together. Uranium (jʊˈreɪniəm is a silvery-gray Metallic Chemical element in the Thorium (ˈθɔːriəm is a Chemical element with the symbol Th and Atomic number 90 This spurred the Curies on to find additional radioactive elements. The Curies first separated out polonium from the pitchblende, and then within a few years, also isolated radium. Radium (ˈreɪdiəm is a radioactive Chemical element which has the symbol Ra and Atomic number 88

Detection

Intensity against photon energy for three isotopes.

Gamma counting

By means of radiometric methods such as gamma spectroscopy (or a method using a chemical separation followed by an activity measurement with a non-energy-dispersive counter), it is possible to measure the concentrations of radioisotopes and to distinguish one from another. Gamma spectroscopy involves the Spectroscopy of Radionuclides. Radioactive decay is the process in which an unstable Atomic nucleus loses energy by emitting ionizing particles and Radiation. 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 In practice, background noise would be present and depending on the detector, the line width would be larger which would make it harder to identify and measure the isotope. Isotopes (Greek isos = "equal" tópos = "site place" are any of the different types of atoms ( Nuclides In biological/medical work it is common to use the natural ⁴⁰K present in all tissues/body fluids as a check of the equipment and as an internal standard. Potassium (pəˈtæsiəm is a Chemical element. It has the symbol K (kalium from qalīy Atomic number 19 and Atomic mass 39

Intensity against alpha energy for four isotopes, note that the line width is narrow and the fine details can be seen.

Intensity against alpha energy for four isotopes, note that the line width is wide and some of the fine details can not be seen. This is for liquid scintillation counting where random effects cause a variation in the number of visible photons generated per alpha decay.

Alpha counting

The best way to test for (and measure) many alpha emitters is to use alpha-particle spectroscopy as it is common to place a drop of the test solution on a metal disk which is then dried out to give a uniform coating on the disk. One method for testing for (and measuring many Alpha emitters is to use alpha-particle spectroscopy. This is then used as the test sample. If the thickness of the layer formed on the disk is too thick then the lines of the spectrum are broadened, this is because some of the energy of the alpha particles is lost during their movement through the layer of active material. 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 An alternative method is to use internal liquid scintillation where the sample is mixed with a scintillation cocktail. When the light emitted is then counted, some machines will record the amount of light energy per radioactive decay event. Due to the imperfections of the liquid scintillation method (such as a failure for all the photons to be detected, cloudy or coloured samples can be difficult to count) and the fact that random quenching can reduce the number of photons generated per radioactive decay it is possible to get a broadening of the alpha spectra obtained through liquid scintillation. It is likely that these liquid scintillation spectra will be subject to a Gaussian broadening rather than the distortion exhibited when the layer of active material on a disk is too thick. Gaussian broadening refers to broadening effects in Spectral lines these can be produced by Doppler broadening and Natural broadening.

A third energy dispersive method for counting alpha particles is to use a semiconductor detector.

From left to right the peaks are due to ²⁰⁹Po, ²¹⁰Po, ²³⁹Pu and ²⁴¹Am. The fact that isotopes such as ²³⁹Pu and ²⁴¹Am have more than one alpha line indicates that the nucleus has the ability to be in different discrete energy levels (like a molecule can). Americium (ˌæməˈrɪsiəm is a Synthetic element that has the symbol Am and Atomic number 95 The nucleus of an Atom is the very dense region consisting of Nucleons ( Protons and Neutrons, at the center of an atom A quantum mechanical system or particle that is bound, confined spacially can only take on certain discrete values of energy as opposed to classical particles which

Occurrence and production

Polonium is a very rare element in nature because of the short half-life of all its isotopes. Half-Life (computer-game page here It's already listed in the disambiguation page It is found in uranium ores at about 100 micrograms per metric ton (1 part in 10¹⁰), which is approximately 0. Uranium (jʊˈreɪniəm is a silvery-gray Metallic Chemical element in the In the Metric system, a microgram is 1/1000000 of a Gram (1 × 10-6 or 1/1000 of a milligram is one of the smallest units of weight/mass commonly used This article is about the tonne or metric ton For other tons see Ton. 2% of the abundance of radium. The amounts in the Earth's crust are not harmful. Polonium has been found in tobacco smoke from tobacco leaves grown with phosphate fertilizers. Tobacco Smoking is the inhalation of smoke from burned dried or cured leaves of the Tobacco plant most often in the form of a Cigarette. ^[19][20]

Neutron capture

Synthesis by (n,γ) reaction

In 1934 an experiment showed that when natural ²⁰⁹Bi is bombarded with neutrons, ²¹⁰Bi is created, which then decays to ²¹⁰Po via β decay. Year 1934 ( MCMXXXIV) was a Common year starting on Monday (link will display full 1934 calendar of the Gregorian calendar. Bismuth (ˈbɪzməθ is a Chemical element that has the symbol Bi and Atomic number 83 This article is a discussion of neutrons in general For the specific case of a neutron found outside the nucleus see Free neutron. The final purification is done pyrochemically followed by liquid-liquid extraction techniques. ^[21][22] Polonium may now be made in milligram amounts in this procedure which uses high neutron fluxes found 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 Only about 100 grams are produced each year, practically all of it in Russia, making polonium exceedingly rare. ^{[23] [24]}

Proton capture

Synthesis by (p, n) and (p,2n) reactions

It has been found that the longer-lived isotopes of polonium can be formed by proton bombardment of bismuth using a cyclotron. The proton ( Greek πρῶτον / proton "first" is a Subatomic particle with an Electric charge of one positive A cyclotron is a type of Particle accelerator. Cyclotrons accelerate Charged particles using a high- Frequency, alternating Voltage (potential Other more neutron rich isotopes can be formed by the irradiation of platinum with carbon nuclei. Carbon (kɑɹbən is a Chemical element with the symbol C and its Atomic number is 6 ^[25]

Applications

When it is mixed or alloyed with beryllium, polonium can be a neutron source: beryllium releases a neutron upon absorption of an alpha particle that is supplied by ²¹⁰Po. 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 Beryllium (bəˈrɪliəm is a Chemical element with the symbol Be and Atomic number 4 Neutron source is a general term referring to a variety devices that emit Neutrons, irrespective of the mechanism used to produce the neutrons This article is a discussion of neutrons in general For the specific case of a neutron found outside the nucleus see Free neutron. 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 It has been used in this capacity as a neutron trigger or initiator for nuclear weapons. A nuclear weapon is an explosive device that derives its destructive force from Nuclear reactions either fission or a combination of fission and fusion. Other uses include the following.

• Devices that eliminate static charges in textile mills and other places. A textile is a flexible material comprised of a network of natural or artificial Fibres often referred to as thread or Yarn. ^[26] However, beta particle sources are more commonly used and are less dangerous. In Nuclear physics, beta decay is a type of Radioactive decay in which a Beta particle (an Electron or a Positron) is emitted A non-radioactive alternative is to use a high-voltage DC power supply to ionise air positively or negatively as required. ^[27]
• ²¹⁰Po can be used as an atomic heat source to power radioisotope thermoelectric generators via thermoelectric materials. A radioisotope thermoelectric generator ( RTG, RITEG) is an Electrical generator which obtains its power from Radioactive decay. Thermoelectricity ( Thermo - Electricity) refers to a class of phenomena in which a Temperature difference creates an Electric potential or an electric
• Because of its very high toxicity, polonium can be used as a poison (see, for example, Alexander Litvinenko poisoning). Alexander Litvinenko was a former officer of Russian Federal Security Service, who escaped prosecution in Russia and received a Political asylum in
• Polonium is also used to get rid of dust on film.

Toxicity

Overview

By mass, polonium-210 is around 250,000 times more toxic than hydrogen cyanide (the actual LD₅₀ for ²¹⁰Po is about 1 microgram for an 80 kg person (see below) compared to about 250 milligram for hydrogen cyanide^[28]). Hydrogen cyanide is a Chemical compound with Chemical formula HCN In Toxicology, the median lethal dose, LD50 (abbreviation for “Lethal Dose 50%” or LCt50 (Lethal Concentration & Time of a In the Metric system, a microgram is 1/1000000 of a Gram (1 × 10-6 or 1/1000 of a milligram is one of the smallest units of weight/mass commonly used For other uses of the words gram or gramme see Gram (disambiguation. The main hazard is its intense radioactivity (as an alpha emitter), which makes it very difficult to handle safely: one gram of Po will self-heat to a temperature of around 500 °C. Even in microgram amounts, handling ²¹⁰Po is extremely dangerous, requiring specialized equipment and strict handling procedures. In the Metric system, a microgram is 1/1000000 of a Gram (1 × 10-6 or 1/1000 of a milligram is one of the smallest units of weight/mass commonly used Alpha particles emitted by polonium will damage organic tissue easily if polonium is ingested, inhaled, or absorbed (though they do not penetrate the epidermis and hence are not hazardous if the polonium is outside the body). Epidermis is the outermost layer of the Skin. It forms the waterproof protective wrap over the body's surface and is made up of stratified squamous Epithelium with

Acute effects

The median lethal dose (LD₅₀) for acute radiation exposure is generally about 4. In Toxicology, the median lethal dose, LD50 (abbreviation for “Lethal Dose 50%” or LCt50 (Lethal Concentration & Time of a 5 Sv. The sievert (symbol Sv is the SI derived unit of dose equivalent. ^[29] The committed effective dose equivalent ²¹⁰Po is 0. The committed effective dose equivalent or CEDE is an estimate of the radiation dose to a person resulting from inhalation or ingestion of a given amount of radioactive substance 51 µSv/Bq if ingested, and 2. The becquerel (symbol Bq) is the SI derived unit of radioactivity. 5 µSv/Bq if inhaled. ^[30] Since ²¹⁰Po has an activity of 166 TBq (4486. 5 Ci) per gram^[30] (1 gram produces 166×10¹² decays per second), a fatal 4. 5 Sv (J/kg) dose can be caused by ingesting 8. The sievert (symbol Sv is the SI derived unit of dose equivalent. 8 MBq (238 microcuries), about 50 nanograms (ng), or inhaling 1. A CURIE (short for Compact URI) is an abbreviated URI expressed in CURIE syntax and may be found in both XML and non-XML grammars 8 MBq (48 microcuries), about 10 ng. A CURIE (short for Compact URI) is an abbreviated URI expressed in CURIE syntax and may be found in both XML and non-XML grammars One gram of ²¹⁰Po could thus in theory poison 20 million people of whom 10 million would die. The actual toxicity of ²¹⁰Po is lower than these estimates, because radiation exposure that is spread out over several weeks (the biological half-life of polonium in humans is 30 to 50 days^[31]) is somewhat less damaging than an instantaneous dose. 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 It has been estimated that a median lethal dose of ²¹⁰Po is 0. In Toxicology, the median lethal dose, LD50 (abbreviation for “Lethal Dose 50%” or LCt50 (Lethal Concentration & Time of a 015 GBq (0. 4 millicuries), or 0. 089 micrograms, still an extremely small amount. ^[32][33]

Long term (chronic) effects

In addition to the acute effects, radiation exposure (both internal and external) carries a long-term risk of death from cancer of 5–10% per Sv. ^[29] The general population is exposed to small amounts of polonium as a radon daughter in indoor air; the isotopes ²¹⁴Po and ²¹⁸Po are thought to cause the majority^[34] of the estimated 15,000-22,000 lung cancer deaths in the US every year that have been attributed to indoor radon. Radon (ˈreɪdɒn is the Chemical element that has the symbol Rn and Atomic number 86 ^[35] Tobacco smoking causes additional exposure to Po. Tobacco Smoking is the inhalation of smoke from burned dried or cured leaves of the Tobacco plant most often in the form of a Cigarette. ^[36]

Regulatory exposure limits

The maximum allowable body burden for ingested ²¹⁰Po is only 1,100 Bq (0. 03 microcurie), which is equivalent to a particle massing only 6. 8 picograms. The maximum permissible workplace concentration of airborne ²¹⁰Po is about 10 Bq/m³ (3 × 10^-10 µCi/cm³). ^[37] The target organs for polonium in humans are the spleen and liver. The spleen is an organ found in all Vertebrate animals In humans the spleen is located in the abdomen of the body where it functions in the destruction of redundant Red The liver is a vital organ in the human body and is present in Vertebrates and some other animals ^[38] As the spleen (150 g) and the liver (1. 3 to 3 kg) are much smaller than the rest of the body, if the polonium is concentrated in these vital organs, it is a greater threat to life than the dose which would be suffered (on average) by the whole body if it were spread evenly throughout the body, in the same way as caesium or tritium (as T₂O). Caesium or cesium (ˈsiːziəm is the Chemical element with the symbol Cs and Atomic number 55 Tritium (ˈtɹɪtiəm symbol or, also known as Hydrogen-3) is a radioactive Isotope of Hydrogen.

²¹⁰Po is widely used in industry, and readily available with little regulation or restriction. In the US, a tracking system run by the Nuclear Regulatory Commission will be implemented in 2007 to register purchases of more than 16 curies of polonium 210 (enough to make up 5,000 lethal doses). The IAEA "is said to be considering tighter regulations. . . There is talk that it might tighten the polonium reporting requirement by a factor of 10, to 1. 6 curies. "^[39]

Famous poisoning cases

Notably, the murder of Alexander Litvinenko, a Russian dissident, in 2006 was announced as due to ²¹⁰Po poisoning ^[40][41] (see Alexander Litvinenko poisoning). Alexander Valterovich Litvinenko (Алекса́ндр Ва́льтерович Литвине́нко ( 30 August 1962 – 23 November 2006 Alexander Litvinenko was a former officer of Russian Federal Security Service, who escaped prosecution in Russia and received a Political asylum in According to Nick Priest, a radiation expert speaking on Sky News on December 2, Litvinenko was probably the first person ever to die of the acute α-radiation effects of ²¹⁰Po. Sky News is a rolling TV news channel providing 24 hour news coverage including the latest breaking news Events 1409 - The University of Leipzig opens 1755 - The second Eddystone Lighthouse is destroyed by fire In Medicine, an acute disease is a disease with either or both of a rapid onset a short course (as opposed to a chronic course ^[42] The Polonium Restaurant in Sheffield (England) experienced increases business as a result of internet searches on the collocation polonium restaurant. Sheffield ( is a city and Metropolitan borough in South Yorkshire, England England is a Country which is part of the United Kingdom. Its inhabitants account for more than 83% of the total UK population whilst its mainland Within the area of Corpus linguistics, collocation is defined as a sequence of words or terms which co-occur more often than would be expected by chance ^{[43] [44]}

It has also been suggested that Irène Joliot-Curie was the first person ever to die from the radiation effects of polonium (due to a single intake) in 1956. Irène Joliot-Curie ( 12 September 1897 &ndash 17 March 1956) was a French scientist the Daughter of Marie Skłodowska-Curie ^[45] She was accidentally exposed to polonium in 1946 when a sealed capsule of the element exploded on her laboratory bench. A decade later, on 17 March 1956, she died in Paris from leukemia which may or may not have been caused by that exposure. Events 45 BC - In his last victory Julius Caesar defeats the Pompeian forces of Titus Labienus and Pompey the Younger Year 1956 ( MCMLVI) was a Leap year starting on Sunday (link will display full calendar of the Gregorian calendar. Leukemia or leukaemia (Greek leukos λευκός, "white" aima αίμα, "blood" is a Cancer of the Blood

According to the book The Bomb in the Basement, several death cases in Israel during 1957-1969 were caused by ²¹⁰Po. For a topic outline on this subject see List of basic Israel topics. ^[46] A leak was discovered at a Weizmann Institute laboratory in 1957. The Weizmann Institute of Science (מכון ויצמן למדע known as Machon Weizmann is a university and research institute in Rehovot, Israel. Traces of ²¹⁰Po were found on the hands of Prof. Dror Sadeh, a physicist who researched radioactive materials. Medical tests indicated no harm, but the tests did not include bone marrow. Sadeh died from cancer. Cancer (medical term Malignant Neoplasm) is a class of Diseases in which a group of cells display uncontrolled One of his students died of leukemia, and two colleagues died after a few years, both from cancer. The issue was investigated secretly, and there was never any formal admission that a connection between the leak and the deaths had existed.

Treatment

It has been suggested that chelation agents such as British Anti-Lewisite (dimercaprol) can be used to decontaminate humans. Chelation therapy is the administration of chelating agents to remove Heavy metals from the body Dimercaprol ( INN) or British anti-Lewisite (abbreviated BAL) is a compound developed by British biochemists at Oxford University during ^[47][48] In one experiment, rats were given a fatal dose of 1. 45 MBq/kg (8. 7 ng/kg) of ²¹⁰Po; all untreated rats were dead after 44 days, but 90% of the rats treated with the chelation agent HOEtTTC remained alive after 5 months. ^[49]

Commercial products containing polonium

No credible nuclear authority has asserted that a commercial product was a likely source for the poisoning of Litvinenko. In Marketing, a product is anything that can be offered to a Market that might satisfy a want or need However, as Prof. Peter D. Zimmerman says, "Polonium 210 is surprisingly common. . . . Polonium sources with about 10 percent of a lethal dose are readily available — even in a product sold on Amazon. com. " [3]

Potentially lethal amounts of polonium are present in anti-static brushes sold to photographers. ^[50] Many of the devices are available by mail order. Mail order is a term which describes the Buying of goods or services by Mail delivery General Electric markets a static eliminator module with 500 microcuries (20 MBq), roughly 2. Electrostatics is the branch of Science that deals with the Phenomena arising from what seems to be stationary Electric charges Since Classical 5 times the lethal dose of ²¹⁰Po if 100%-ingested, for US $71;^[51] Staticmaster sells replacement units with the same amount (500 mCi) of ²¹⁰Po for $36. ^[52] In USA, the devices with no more than 500 mCi of (sealed) ²¹⁰Po per unit can be bought in any amount under a "general license" [4] which means that a buyer needn't be registered by any authorities: the general license "is effective without the filing of an application with the Commission or the issuance of a licensing document to a particular person. "

If these sources were used to collect the amount of polonium likely used in the poisoning—and one could devise a method of separating the polonium from its protective casing—it would take 10-100 modules for price of US $360 to $7,100. That such a thing could be done is extremely difficult according to the manufacturers and would be highly dangerous to anyone attempting to do so without some special equipment like a glovebox. A glovebox (or glove box) is a sealed container that is designed to allow one to manipulate objects while being in a different atmosphere from the object

Sometimes sources of polonium used in industry are stolen or lost. According to the National Regulatory Commission, there were registered at least 8 cases of loss of control of potentially lethal polonium sources in the USA during 2006. [5]. Tiny amounts of such radioisotopes are sometimes used in the laboratory and for teaching purposes — typically of the order of 4–40 kBq (0. 1–1. 0 μCi), in the form of sealed sources, with the Po deposited on a substrate or in a resin or polymer matrix—are often exempt from licensing by NRC and similar authorities as they are not considered hazardous. Small amounts of ²¹⁰Po are available to the public in the United States by mail order from a company called United Nuclear as 'needle sources' for laboratory experimentation. It would require about 15,000 ²¹⁰Po of these sources at a total cost of about $1 million to obtain a toxic quantity of Polonium. They typically sell between 4 and 8 sources per year. ^[53][54]

According to some estimates,^[55] the cost of the quantity of pure Polonium-210 used to kill Litvinenko would be around £20 million (US $39 million). ^[56] However, this estimation is based on retail prices of commercially available demonstration radiation sources with very small activities and cannot be considered as reasonable.

See also

• Polonium - Radon Decay Chain [6]
• Polonium halo

References

External links

References and External links verified 2006-11-25 unless noted. Year 2006 ( MMVI) was a Common year starting on Sunday of the Gregorian calendar. Events 1034 - Máel Coluim mac Cináeda, King of Scots dies Donnchad, the

• WebElements.com – Polonium
• History of Polonium
• Los Alamos National Laboratory – Polonium
• NLM Hazardous Substances Databank – Polonium, Radioactive
• The Human Plutonium Injection Experiments (Polonium experiments - pg20)
• Build a pocket-sized ion chamber, useful for detecting Polonium