40 yttrium ← zirconium → niobium Ti ↑ Zr ↓ Hf Periodic Table - Extended Periodic Table
General
Name, Symbol, Number	zirconium, Zr, 40
Chemical series	transition metals
Group, Period, Block	4, 5, d
Appearance	silvery white
Standard atomic weight	91. Yttrium (ˈɪtriəm is a Chemical element with symbol Y and Atomic number 39 Niobium (naɪˈoʊbiəm or columbium (/kəˈlʌmbiəm/ is a Chemical element that has the symbol Nb and Atomic number 41 Titanium (taɪˈteɪniəm is a Chemical element with the symbol Ti and Atomic number 22 Hafnium (ˈhæfniəm is a Chemical element that has the symbol Hf and Atomic number 72 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 In Chemistry, the term transition metal (sometimes also called a transition element) has two possible meanings It commonly refers to any element in 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 Biological occurances The group 4 elements are not known to be involved in the biological chemistry of any living systems A period 5 element is one of the Chemical elements in the fifth row (or period) of the periodic table of the elements. The d-block of the periodic table of the elements consists of those Periodic table groups that contain elements in which in the atomic ground state the highest-energy 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 224(2)  g·mol−1
Electron configuration	[Kr] 4d2 5s2
Electrons per shell	2, 8, 18, 10, 2
Physical properties
Phase	solid
Density (near r.t.)	6. In Atomic physics and Quantum chemistry, electron configuration is the arrangement of Electrons in an Atom, Molecule, or other Krypton (ˈkrɪptən or /ˈkrɪptɒn/ from kryptos "hidden" is a Chemical element with the symbol Kr and Atomic number 36 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 52  g·cm−3
Liquid density at m.p.	5. 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. 8  g·cm−3
Melting point	2128 K (1855 °C, 3371 °F)
Boiling point	4682 K (4409 °C, 7968 °F)
Heat of fusion	14  kJ·mol−1
Heat of vaporization	573  kJ·mol−1
Specific heat capacity	(25 °C) 25. 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 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 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 36  J·mol−1·K−1
Vapor pressure P(Pa) 1 10 100 1 k 10 k 100 k at T(K) 2639 2891 3197 3575 4053 4678
Atomic properties
Crystal structure	hexagonal close-packed
Oxidation states	4, 3,[1] 2, 1,[2] (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 33 (Pauling scale)
Ionization energies (more)	1st:  640. The ionization potential, ionization energy or EI of an Atom or Molecule is the Energy required to remove an Electron These tables list the Ionization energy in kJ/mol necessary to remove one mole of Electrons from one mole of neutral gaseous Atoms (first energy respectively 1  kJ·mol−1
	2nd:  1270  kJ·mol−1
	3rd:  2218  kJ·mol−1
Atomic radius	155  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 )	206  pm
Covalent radius	148  pm
Miscellaneous
Magnetic ordering	no data
Electrical resistivity	(20 °C) 421 n Ω·m
Thermal conductivity	(300 K) 22. The covalent radius, r cov is a measure of the size of Atom which forms part of a Covalent bond. 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. In Physics, thermal conductivity, k is the property of a material that indicates its ability to conduct Heat. 6  W·m−1·K−1
Thermal expansion	(25 °C) 5. 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) 3800 m/s
Young's modulus	68  GPa
Shear modulus	33  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 34
Mohs hardness	5. The Mohs scale of mineral hardness characterizes the scratch resistance of various Minerals through the ability of a harder material to scratch a softer material 0
Vickers hardness	903  MPa
Brinell hardness	650  MPa
CAS registry number	7440-67-7
Selected isotopes
Main article: Isotopes of zirconium iso NA half-life DM DE (MeV) DP 88Zr syn 83.4 d ε - 88Y γ 0. The Vickers hardness test was developed in 1924 by Smith and Sandland as an alternative method to measure the Hardness of materials The Brinell scale characterizes the indentation Hardness of materials through the scale of penetration of an indenter loaded on a material test-piece CAS registry numbers are unique numerical identifiers for Chemical compounds Polymers biological sequences mixtures and Alloys They are also referred to Naturally occurring Zirconium ( Zr) is composed of four stable isotopes and one extremely long-lived Radioisotope (96Zr which decays via 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 106 seconds and 107 seconds (approximately 11 Electron capture (sometimes called inverse beta decay) is a Decay mode for Isotopes that will occur when there are too many Protons in the Yttrium (ˈɪtriəm is a Chemical element with symbol Y and Atomic number 39 Gamma rays (denoted as &gamma) are a form of Electromagnetic radiation or light emission of frequencies produced by sub-atomic particle interactions 392D - 89Zr syn 78.4 h ε - 89Y β+ 0. Delayed nuclear radiation can occur in a Nuclear decay. It happens when an Isotope decays into a very short-lived isotope and then decays again to a relatively long-lived 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 105 seconds and 106 seconds (approximately 27 Electron capture (sometimes called inverse beta decay) is a Decay mode for Isotopes that will occur when there are too many Protons in the Yttrium (ˈɪtriəm is a Chemical element with symbol Y and Atomic number 39 Positron emission is a type of Beta decay, sometimes referred to as " beta plus " (&beta+ 902 89Y γ 0. Yttrium (ˈɪtriəm is a Chemical element with symbol Y and Atomic number 39 Gamma rays (denoted as &gamma) are a form of Electromagnetic radiation or light emission of frequencies produced by sub-atomic particle interactions 909D - 90Zr 51. Delayed nuclear radiation can occur in a Nuclear decay. It happens when an Isotope decays into a very short-lived isotope and then decays again to a relatively long-lived 45% 90Zr is stable with 50 neutrons 91Zr 11. Stable isotopes are chemical isotopes that are not Radioactive (to current knowledge This article is a discussion of neutrons in general For the specific case of a neutron found outside the nucleus see Free neutron. 22% 91Zr is stable with 51 neutrons 92Zr 17. Stable isotopes are chemical isotopes that are not Radioactive (to current knowledge This article is a discussion of neutrons in general For the specific case of a neutron found outside the nucleus see Free neutron. 15% 92Zr is stable with 52 neutrons 93Zr syn 1.53×106y β− 0. Stable isotopes are chemical isotopes that are not Radioactive (to current knowledge This article is a discussion of neutrons in general For the specific case of a neutron found outside the nucleus see Free neutron. 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 In Nuclear physics, beta decay is a type of Radioactive decay in which a Beta particle (an Electron or a Positron) is emitted 060 93Nb 94Zr 17. Niobium (naɪˈoʊbiəm or columbium (/kəˈlʌmbiəm/ is a Chemical element that has the symbol Nb and Atomic number 41 38% 1. 1 × 1017 y β−β− - 94Mo 96Zr 2. In the process of Beta decay, unstable nuclei decay by converting a Neutron in the nucleus to a Proton and emitting an Electron and an electron Molybdenum (məˈlɪbdənəm from the Greek word for the metal " Lead " is a Group 6 Chemical element with the symbol Mo 8% 2.0×1019y[3] β−β− 3. To help compare Orders of magnitude of different times this page lists times longer than 1019 Seconds (317 billion years In the process of Beta decay, unstable nuclei decay by converting a Neutron in the nucleus to a Proton and emitting an Electron and an electron 348 96Mo
References

Zirconium (pronounced /zɚˈkoʊniəm/, /ˌzɝˈkoʊniəm/) is a chemical element with the symbol Zr and atomic number 40. Molybdenum (məˈlɪbdənəm from the Greek word for the metal " Lead " is a Group 6 Chemical element with the symbol Mo 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 It is a lustrous, gray-white, strong transition metal that resembles titanium. In Chemistry, the term transition metal (sometimes also called a transition element) has two possible meanings It commonly refers to any element in Titanium (taɪˈteɪniəm is a Chemical element with the symbol Ti and Atomic number 22 Zirconium is used as an alloying agent due to its high resistance to corrosion. It is never found as a native metal, but is instead obtained mainly from the mineral zircon, which can be purified by chlorine. Zircon is a Mineral belonging to the group of nesosilicates. Its chemical name is Zirconium silicate and its corresponding chemical formula is Chlorine (ˈklɔriːn from the Greek word 'χλωρóς' ( khlôros, meaning 'pale green' is the Chemical element with Atomic number 17 and Zirconium was first isolated in an impure form in 1824 by Berzelius. Friherre Jöns Jacob Berzelius (20 August 1779 &ndash 7 August 1848 was a Swedish chemist

Zirconium has no known biological role. Zirconium forms both inorganic and organic compounds, such as zirconium dioxide and zirconocene dibromide, respectively. Inorganic chemistry is the branch of Chemistry concerned with the properties and behavior of Inorganic compounds This field covers all Chemical compounds Organic chemistry is a discipline within Chemistry which involves the scientific study of the structure properties composition reactions, and preparation Zirconia redirects here For the Sailor Moon character see Dead Moon Circus. There are five naturally-occurring isotopes, three of which are stable. Isotopes (Greek isos = "equal" tópos = "site place" are any of the different types of atoms ( Nuclides Short-term exposure to zirconium powder causes minor irritation, and inhalation of zirconium compounds can cause skin and lung granulomas. In Medicine ( Anatomical pathology) a granuloma (classical Latin plural granulomata; modern anglicized plural granulomas, also accepted

Contents 1 Characteristics 2 Applications 2.1 Refining 3 History 4 Occurrence 4.1 Geological 4.2 Biological 5 Compounds 6 Isotopes 7 Toxicity 8 See also 9 Notes 10 External links

Characteristics

Zirconium is a lustrous, grayish-white, soft, ductile, and malleable metal which is solid at room temperature, though it becomes hard and brittle at lower purities. Lustre (or luster) is a description of the way light interacts with the surface of a Crystal, rock, or Mineral. Ductility is a mechanical property used to describe the extent to which materials can be deformed plastically or "stretched" into "wires" without For malleability in Cryptography, see Malleability (cryptography. ^[4][5] In powder form, zirconium is highly flammable, but the solid form is far less prone to igniting. ^[6] Zirconium is highly resistant to corrosion by alkalis, acids, salt water, and other agents. ^[7] However, it will dissolve in hydrochloric and sulfuric acid, especially when fluorine is present. Hydrochloric acid is the Solution of Hydrogen chloride ( H[[Chlorine Cl]] in water Sulfuric (or sulphuric acid, H 2 S[[oxygen O]]4 is a strong Mineral acid. Fluorine, fluorum meaning "to flow" is the Chemical element with the symbol F and Atomic number 9 ^[8] Alloys with zinc become magnetic below 35 K. ^[6]

The melting point of zirconium is at 1855°C, and the boiling point is at 4409°C. ^[6] Zirconium has an electronegativity of 1. " Electronegativity " is the opposite of " Electropositivity," which describes an element's ability to donate electrons 33 on the Pauling scale. Of the elements within d-block, Zirconium has the fourth lowest electronegativity after yttrium, lutetium, and hafnium. The d-block of the periodic table of the elements consists of those Periodic table groups that contain elements in which in the atomic ground state the highest-energy Yttrium (ˈɪtriəm is a Chemical element with symbol Y and Atomic number 39 Lutetium (ljuːˈtiːʃiəm is a Chemical element with the symbol Lu and Atomic number 71 Hafnium (ˈhæfniəm is a Chemical element that has the symbol Hf and Atomic number 72 ^[9]

Applications

Because of Zirconium's excellent resistance to corrosion, it is often used as an alloying agent in materials that are exposed to corrosive agents, such as surgical appliances, explosive primers, vacuum tube getters and filaments. Getters are reactive materials used for removing traces of gas from vacuum systems Zirconium dioxide (ZrO₂) is used in laboratory crucibles, metallurgical furnaces, and as a refractory material. ^[6] Zircon (ZrSiO₄) is cut into gemstones for use in jewelry. Zirconium carbonate (3ZrO₂·CO₂·H₂O) was used in lotions to treat poison ivy, but this was discontinued as it caused bad skin reactions in some cases. ^[4] 90% of all zirconium produced is used in nuclear reactors because of its low neutron-capture cross-section and resistance to corrosion. ^[6][5] Zirconium alloys are used in space vehicle parts for their resistance to heat, an important quality given the extreme heat associated with atmospheric reentry. ^[10] Zirconium is also a component in some abrasives, such as grinding wheels and sandpaper. An abrasive is a material often a Mineral, that is used to shape or finish a workpiece through rubbing which leads to part of the workpiece being worn away Abrasive Paper is a form of Paper where an Abrasive material has been fixed to its surface ^[11]

Refining

Upon being collected from coastal waters, the solid mineral zircon is purified by spiral concentrators to remove excess sand and gravel and by magnetic separators to remove ilmenite and rutile. Zircon is a Mineral belonging to the group of nesosilicates. Its chemical name is Zirconium silicate and its corresponding chemical formula is Ilmenite is a weakly magnetic titanium-iron oxide Mineral which is iron-black or steel-gray Rutile is a Mineral composed primarily of Titanium dioxide, Ti[[oxygen O]]2 The byproducts can then be dumped back into the water safely, as they are all natural components of beach sand. The refined zircon is then purified into pure zirconium by chlorine or other agents, then sintered until sufficiently ductile for metalworking. Chlorine (ˈklɔriːn from the Greek word 'χλωρóς' ( khlôros, meaning 'pale green' is the Chemical element with Atomic number 17 and Sintering is a method for making objects from powder, by heating the material (below its Melting point - solid state sintering until its particles adhere ^[5] Zirconium and hafnium are both contained in zircon and they are quite difficult to separate due to their similar chemical properties. Hafnium (ˈhæfniəm is a Chemical element that has the symbol Hf and Atomic number 72 ^[10]

History

The zirconium-containing mineral zircon, or its variations (jargoon, hyacinth, jacinth, ligure), were mentioned in biblical writings. Zircon is a Mineral belonging to the group of nesosilicates. Its chemical name is Zirconium silicate and its corresponding chemical formula is A Jargoon or jargon (occasionally in old writings jargounce and jacounce) is name applied by gemologists to those Zircons which are Jacinth is a red transparent variety of Zircon used as a gemstone ^[6][10] The mineral was not known to contain a new element until 1789,^[11] when Klaproth analyzed a jargoon from the island of Ceylon in the Indian Ocean. Martin Heinrich Klaproth ( 1 December 1743 – 1 January 1817) was a German Chemist. Sri Lanka, officially the Democratic Socialist Republic of Sri Lanka ( Sinhalese:, இலங்கை known as Ceylon before 1972 is an Island He named the new element Zirkonerde (zirconia). ^[7][6] Humphry Davy attempted to isolate this new element in 1808 through electrolysis, but failed. Sir Humphry Davy 1st Baronet FRS MRIA (17 December 1778 &ndash 29 May 1829 was a British Chemist and inventor ^[4] Zirconium (from Syriac zargono,^[12] Arabic zarkûn from Persian zargûn زرگون meaning "gold like")^[10] was first isolated in an impure form in 1824 by Berzelius by heating a mixture of potassium and potassium-zirconium fluoride in a small decomposition process conducted in an iron tube. See Syriac (disambiguation for other uses Syriac (syr ܠܫܢܐ ܣܘܪܝܝܐ leššānā Suryāyā) is an Eastern Aramaic language Arabic (ar الْعَرَبيّة (informally ar عَرَبيْ) in terms of the number of speakers is the largest living member of the Semitic language Friherre Jöns Jacob Berzelius (20 August 1779 &ndash 7 August 1848 was a Swedish chemist ^[7][6]

The crystal bar process (or Iodide process), discovered by Anton Eduard van Arkel and Jan Hendrik de Boer in 1925, was the first industrial process for the commercial production of pure metallic zirconium. The crystal bar process (or iodide process) was discovered by Anton Eduard van Arkel and Jan Hendrik de Boer in 1925 Anton Eduard van Arkel, ( 's-Gravenzande Netherlands, November 19, 1893 &ndash Leiden, March 14 1976) was a The process involved thermally decomposing zirconium tetraiodide. It was superseded in 1945 by a much cheaper process developed by William Justin Kroll, in which zirconium tetrachloride is broken down by magnesium. The Kroll process is a Pyrometallurgical industrial process used to produce metallic Titanium. See also German classic philologist Wilhelm Kroll (philologist (1869-1939 Kroll: William Justin Kroll (born Guillaume Justin ^[5][13]

Occurrence

Geological

Zirconium has a concentration of about 130 mg/kg within the earth's crust and about . 026 μg/L in sea water,^[14] though it is never found in nature as a native metal. A native metal is any of a number of Metals that can be found freely in nature The principal commercial source of zirconium is the zirconium silicate mineral, zircon (ZrSiO₄),^[4] which is found primarily in Australia, Brazil, India, Russia, South Africa, and the United States, as well as in smaller deposits around the world. The silicate minerals make up the largest and most important class of rock-forming Minerals They are classified based on the structure of their silicate Ion group Zircon is a Mineral belonging to the group of nesosilicates. Its chemical name is Zirconium silicate and its corresponding chemical formula is ^[5] 80% of zircon mining occurs in Australia and South Africa. ^[4] Zircon resources exceed 60 million metric tons worldwide^[15] and annual worldwide zirconium production is approximately 900,000 metric tons. Zircon is a Mineral belonging to the group of nesosilicates. Its chemical name is Zirconium silicate and its corresponding chemical formula is ^[14]

Zircon is a by-product of the mining and processing of the titanium minerals ilmenite and rutile, as well as tin mining. Titanium (taɪˈteɪniəm is a Chemical element with the symbol Ti and Atomic number 22 Ilmenite is a weakly magnetic titanium-iron oxide Mineral which is iron-black or steel-gray Rutile is a Mineral composed primarily of Titanium dioxide, Ti[[oxygen O]]2 Tin is a Chemical element with the symbol Sn (stannum and Atomic number 50 ^[16] From 2003 to 2007, zircon prices have steadily increased from $360 to $840 per metric ton. ^[15] Zirconium also occurs in more than 140 other recognized mineral species including baddeleyite and kosnarite. Baddeleyite is a rare zirconium oxide Mineral ( Zr[[oxygen O]]2 or Zirconia) occurring in a variety of Monoclinic prismatic crystal ^[17] This metal is commercially produced mostly by the reduction of the zirconium(IV) chloride with magnesium metal in the Kroll process. The chloride Ion is formed when the element Chlorine picks up one Electron to form an Anion (negatively-charged ion Cl&minus Magnesium (mægˈniːziəm is a Chemical element with the symbol Mg, Atomic number 12 Atomic weight 24 The Kroll process is a Pyrometallurgical industrial process used to produce metallic Titanium. ^[6] Commercial-quality zirconium for most uses still has a content of 1% to 3% hafnium. ^[4]

This element is relatively-abundant in S-type stars, and it has been detected in the sun and in meteorites. In Astronomy, stellar classification is a classification of Stars based initially on photospheric temperature and its associated Spectral characteristics Lunar rock samples brought back from several Apollo program missions to the moon have a quite high zirconium oxide content relative to terrestrial rocks. ^[7]

See also zirconium minerals.

Biological

Zirconium has no known biological role, though zirconium salts are of low toxicity. The human body contains, on average, only 1 milligram of zirconium, and daily intake is approximately 50 μg per day. Zirconium content in human blood is as low as 10 parts per billion. Aquatic plants readily take up soluble zirconium, but it is rare in land plants. 70% of plants have no zirconium content at all, and those that do have as little as 5 parts per billion. ^[4]

Compounds

As a transition metal, zirconium forms various inorganic compounds, such as zirconium dioxide (ZrO₂). In Chemistry, the term transition metal (sometimes also called a transition element) has two possible meanings It commonly refers to any element in Inorganic chemistry is the branch of Chemistry concerned with the properties and behavior of Inorganic compounds This field covers all Chemical compounds Zirconia redirects here For the Sailor Moon character see Dead Moon Circus. This compound, also referred to as zirconia, has exceptional fracture toughness and chemical resistance, especially in its cubic form. In Materials science, fracture toughness is a property which describes the ability of a material containing a crack to resist Fracture, and is one of the most important Cubic zirconia (or CZ) the cubic crystalline form of Zirconium dioxide ( ZrO2) is a Mineral that is widely synthesized ^[18] These properties make zirconia useful as a thermal barrier coating,^[19] though it is also a common diamond substitute. In Mineralogy, diamond is the allotrope of carbon where the carbon atoms are arranged in ^[18] Zirconium tungstate is an unusual substance in that it shrinks in all directions when heated, whereas other elements expand when heated. Zr(WO42, or zirconium tungstate is a metal Oxide with unusual properties ^[6] ZrZn₂ is one of only two substances to exhibit superconductivity and ferromagnetism simultaneously, with the other being UGe₂. Superconductivity is a phenomenon occurring in certain Materials generally at very low Temperatures characterized by exactly zero electrical resistance Ferromagnetism is the basic mechanism by which certain materials (such as Iron) form Permanent magnets and/or exhibit strong interactions with Magnets it ^[20] Other inorganic zirconium compounds include zirconium (II) hydride, zirconium nitride, and zirconium tetrachloride (ZrCl₄), which is used in the Friedel-Crafts reaction. Zirconium(IV chloride, also known as zirconium tetrachloride, is the Inorganic compound with the formula ZrCl4 The Friedel-Crafts reactions are a set of reactions developed by Charles Friedel and James Crafts in 1877. ^[21]

Organozirconium chemistry is the study of compounds containing a carbon-zirconium bond. Organozirconium compounds are Organometallic compounds containing a Carbon to Zirconium Chemical bond. Carbon (kɑɹbən is a Chemical element with the symbol C and its Atomic number is 6 These organozirconium compounds are often employed as polymerization catalysts. The first such compound was zirconocene dibromide, prepared in 1952 by John M. Birmingham at Harvard University. ^[22] Schwartz's reagent, prepared in 1970 by P. C. Wailes and H. Weigold,^[23] is a metallocene used in organic synthesis for transformations of alkenes and alkynes. A metallocene is a compound with the general formula (C5R52M consisting of two cyclopentadienyl anions (Cp bound to a metal center in the oxidation Organic synthesis is a special branch of Chemical synthesis and is concerned with the construction of Organic compounds via Organic reactions Organic In Organic chemistry, an alkene, olefin, or olefine is an unsaturated Chemical compound containing at least one Carbon Alkynes are Hydrocarbons that have at least one Triple bond between two Carbon atoms with the formula CnH2n-2. ^[24]

Isotopes

Main article: Isotopes of zirconium

Naturally-occurring zirconium is composed of five isotopes. Naturally occurring Zirconium ( Zr) is composed of four stable isotopes and one extremely long-lived Radioisotope (96Zr which decays via ⁹⁰Zr, ⁹¹Zr, and ⁹²Zr are stable. ⁹⁴Zr has a half-life of 1. 10 × 10¹⁷ years. ⁹⁶Zr has half-life of 2. 4 × 10¹⁹ years, making it the longest-lived radioisotope of zirconium. Of these natural isotopes, ⁹⁰Zr is the most common, making up 51. 45% of all zirconium. ⁹⁶Zr is the least common, comprising only 2. 80% of zirconium. ^[25]

28 artificial isotopes of zirconium have been synthesized, ranging in atomic mass from 78 to 110. ⁹³Zr is the longest-lived artificial isotope, with a half-life of 1. 93Zr is a Radioisotope of Zirconium with a Half life of 153 million years decaying with a low-energy Beta particle to Niobium 53 × 10⁶ years. ¹¹⁰Zr, the heaviest isotope of Zirconium, is also the shortest-lived, with an estimated half-life of only 30 milliseconds. Radioactive isotopes at or above mass number 93 decay by β^-, whereas those at or below 89 decay by β⁺. In Nuclear physics, beta decay is a type of Radioactive decay in which a Beta particle (an Electron or a Positron) is emitted In Nuclear physics, beta decay is a type of Radioactive decay in which a Beta particle (an Electron or a Positron) is emitted The only exception is ⁸⁸Zr, which decays by ε. Electron capture (sometimes called inverse beta decay) is a Decay mode for Isotopes that will occur when there are too many Protons in the ^[25]

Zirconium also has six metastable isomers, ^83mZr, ^85mZr, ^89mZr, ^90m1Zr, ^90m2Zr, and ^91mZr. 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 Of these, ^90m2Zr has the shortest half-life at 131 nanoseconds. ^89mZr is the longest lived with a half-life of 4. 161 minutes. ^[25]

Toxicity

Ingestion or inhalation of ⁹³Zr, a radioactive isotope, causes a slight increase in the likelihood of developing cancer. ^[14] Short-term exposure to zirconium powder can cause irritation, but only contact with the eyes requires medical attention. ^[26] Inhalation of zirconium compounds can cause skin and lung granulomas. In Medicine ( Anatomical pathology) a granuloma (classical Latin plural granulomata; modern anglicized plural granulomas, also accepted Zirconium aerosols can cause pulmonary granulomas. lung is the essential Respiration organ in air-breathing Animals including most Tetrapods a few Fish and a few Snails The most primitive Persistent exposure to zirconium tetrachloride resulted in increased mortality in rats and guinea pigs and a decrease of blood hemoglobin and red blood cells in dogs. OSHA recommends a 5 mg/m³ time weighted average limit and a 10 mg/m³ short-term exposure limit. The Permissible Exposure Limit ( PEL or OSHA PEL) is a legal limit in the United States for exposure of an employee to a Substance ^[27]

See also

• Zirconium compounds

Notes

External links

• WebElements.com – Zirconium
• Los Alamos National Laboratory – Zirconium

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