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Encyclopedia > Strontium
38 rubidiumstrontiumyttrium
Ca

Sr

Ba
General
Name, Symbol, Number strontium, Sr, 38
Chemical series alkaline earth metals
Group, Period, Block 2, 5, s
Appearance silvery white metallic
Standard atomic weight 87.62(1) g·mol−1
Electron configuration [Kr] 5s2
Electrons per shell 2, 8, 18, 8, 2
Physical properties
Phase solid
Density (near r.t.) 2.64 g·cm−3
Liquid density at m.p. 2.375 g·cm−3
Melting point 1050 K
(777 °C, 1431 °F)
Boiling point 1655 K
(1382 °C, 2520 °F)
Heat of fusion 7.43 kJ·mol−1
Heat of vaporization 136.9 kJ·mol−1
Heat capacity (25 °C) 26.4 J·mol−1·K−1
Vapor pressure
P(Pa) 1 10 100 1 k 10 k 100 k
at T(K) 796 882 990 1139 1345 1646
Atomic properties
Crystal structure cubic face centered
Oxidation states 2
(strongly basic oxide)
Electronegativity 0.95 (scale Pauling)
Ionization energies
(more)
1st: 549.5 kJ·mol−1
2nd: 1064.2 kJ·mol−1
3rd: 4138 kJ·mol−1
Atomic radius 200 pm
Atomic radius (calc.) 219 pm
Covalent radius 192 pm
Miscellaneous
Magnetic ordering paramagnetic
Electrical resistivity (20 °C) 132 n Ω·m
Thermal conductivity (300 K) 35.4 W·m−1·K−1
Thermal expansion (25 °C) 22.5 µm·m−1·K−1
Shear modulus 6.1 GPa
Poisson ratio 0.28
Mohs hardness 1.5
CAS registry number 7440-24-6
Selected isotopes
Main article: Isotopes of strontium
iso NA half-life DM DE (MeV) DP
82Sr syn 25.36 d ε - 82Rb
83Sr syn 1.35 d ε - 83Rb
β+ 1.23 83Rb
γ 0.76, 0.36 -
84Sr 0.56% Sr is stable with 46 neutrons
85Sr syn 64.84 d ε - 85Rb
γ 0.514D -
86Sr 9.86% Sr is stable with 48 neutrons
87Sr 7.0% Sr is stable with 49 neutrons
88Sr 82.58% Sr is stable with 50 neutrons
89Sr syn 50.52 d ε 1.49 89Rb
β- 0.909D 89Y
90Sr syn 28.90 y β- 0.546 90Y
References

Strontium (IPA: /ˈstrɒntiəm/) is a chemical element in the periodic table that has the symbol Sr and the atomic number 38. An alkaline earth metal, strontium is a soft silver-white or yellowish metallic element that is highly reactive chemically. The metal turns yellow when exposed to air. It occurs naturally in the minerals celestine and strontianite. The 90Sr isotope is present in radioactive fallout and has a half-life of 28.90 years. General Name, Symbol, Number rubidium, Rb, 37 Chemical series alkali metals Group, Period, Block 1, 5, s Appearance grey white Atomic mass 85. ... General Name, Symbol, Number yttrium, Y, 39 Chemical series transition metals Group, Period, Block 3, 5, d Appearance silvery white Atomic mass 88. ... For other uses, see Calcium (disambiguation). ... For other uses, see Barium (disambiguation). ... Image File history File links File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... This is a standard display of the periodic table of the elements. ... An extended periodic table was suggested by Glenn T. Seaborg in 1969. ... This is a list of chemical elements, sorted by name and color coded according to type of element. ... A table of chemical elements ordered by atomic number and color coded according to type of element. ... A group, also known as a family, is a vertical column in the periodic table of the chemical elements. ... The alkaline earth metals are the series of elements in Group 2 (IUPAC style) of the periodic table: beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba) and radium (Ra) (not always considered due to its radioactivity and very short half-life). ... A group, also known as a family, is a vertical column in the periodic table of the chemical elements. ... In the periodic table of the elements, a period is a horizontal row of the table. ... A block of the periodic table of elements is a set of adjacent groups. ... The alkaline earth metals are the series of elements in Group 2 of the periodic table: beryllium, magnesium, calcium, strontium, barium and radium (not always considered due to its very short half-life). ... A period 5 element is one of the chemical elements in the fifth row (or period) of the periodic table of the elements. ... The s-block of the periodic table of elements consists of the first two groups: the alkali metals and alkaline earth metals, plus hydrogen. ... Color is an important part of the visual arts. ... Strontium sample. ... The atomic mass (ma) is the mass of an atom at rest, most often expressed in unified atomic mass units. ... To help compare different orders of magnitude we list here masses between 60. ... Hydrogen = 1 List of Elements in Atomic Number Order. ... Electron atomic and molecular orbitals In atomic physics and quantum chemistry, the electron configuration is the arrangement of electrons in an atom, molecule, or other physical structure (, a crystal). ... For other uses, see Krypton (disambiguation). ... For other uses, see Electron (disambiguation). ... Example of a sodium electron shell model An electron shell, also known as a main energy level, is a group of atomic orbitals with the same value of the principal quantum number n. ... In the physical sciences, a phase is a set of states of a macroscopic physical system that have relatively uniform chemical composition and physical properties (i. ... For other uses, see Solid (disambiguation). ... For other uses, see Density (disambiguation). ... For other uses, see Room temperature (disambiguation). ... For other uses, see Density (disambiguation). ... The melting point of a crystalline solid is the temperature range at which it changes state from solid to liquid. ... The melting point of a crystalline 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. ... Celsius is, or relates to, the Celsius temperature scale (previously known as the centigrade scale). ... For other uses, see Fahrenheit (disambiguation). ... Italic text This article is about the boiling point of liquids. ... The kelvin (symbol: K) is a unit increment of temperature and is one of the seven SI base units. ... Celsius is, or relates to, the Celsius temperature scale (previously known as the centigrade scale). ... For other uses, see Fahrenheit (disambiguation). ... Standard enthalpy change of fusion of period three. ... The joule per mole (symbol: J·mol-1) is an SI derived unit of energy per amount of material. ... The standard enthalpy change of vaporization, ΔvHo, also (less correctly) known as the heat of vaporization is the energy required to transform a given quantity of a substance into a gas. ... The joule per mole (symbol: J·mol-1) is an SI derived unit of energy per amount of material. ... To meet Wikipedias quality standards, this article or section may require cleanup. ... Vapor pressure is the pressure of a vapor in equilibrium with its non-vapor phases. ... Enargite crystals In mineralogy and crystallography, a crystal structure is a unique arrangement of atoms in a crystal. ... The oxidation number of an element in a molecule or complex is the charge that it would have if all the ligands (basically, atoms that donate electrons) were removed along with the electron pairs that were shared with the central atom[1]. It means that the oxidation number is the... Acids and bases: Acid-base reaction pH Self-ionization of water Buffer solutions Systematic naming Acid-base extraction Acidity function Proton affinity Acids: Strong acids Weak acids Superacids Lewis acids Mineral acids Organic acids Bases: Strong bases Weak bases Superbases Lewis bases Organic bases edit In chemistry, a base is... Electronegativity is a measure of the ability of an atom or molecule to attract electrons in the context of a chemical bond. ... The ionization energy (IE) of an atom or of a molecule is the energy required to strip it of an electron. ... These tables list the ionization energy in kJ/mol necessary to remove an electron from a neutral atom (first energy), respectively from a singly, doubly, etc. ... Kilojoule per mole are an SI derived unit of energy per amount of material, where energy is measured in units of 1000 joules, and the amount of material is measured in mole units. ... Atomic radius: Ionic radius Covalent radius Metallic radius van der Waals radius edit Atomic radius, and more generally the size of an atom, is not a precisely defined physical quantity, nor is it constant in all circumstances. ... You have big harry skanky balls ... One picometre is defined as 1x10-12 metres, in standard units. ... You have big harry skanky balls ... Atomic radius: Ionic radius Covalent radius Metallic radius van der Waals radius edit The covalent radius, rcov, is a measure of the size of atom which forms part of a covalent bond. ... You have big harry skanky balls ... For other senses of this word, see magnetism (disambiguation). ... Simple Illustration of a paramagnetic probe made up from miniature magnets. ... // Headline text POOP!! Danny Hornsby (also known as Gnome) is a measure indicating how strongly a Gnome can opposes the flow of electric current. ... In physics, thermal conductivity, k, is the intensive property of a material that indicates its ability to conduct heat. ... During heat transfer, the energy that is stored in the intermolecular bonds between atoms changes. ... In materials science, shear modulus, G, or sometimes S or μ, sometimes referred to as the modulus of rigidity, is defined as the ratio of shear stress to the shear strain:[1] where = shear stress; force acts on area ; = shear strain; length changes by amount . ... Figure 1: Rectangular specimen subject to compression, with Poissons ratio circa 0. ... This article or section does not cite any references or sources. ... CAS registry numbers are unique numerical identifiers for chemical compounds, polymers, biological sequences, mixtures and alloys. ... Strontium (Sr) Standard atomic mass: 87. ... For other uses, see Isotope (disambiguation). ... Natural abundance refers to the prevalence of different isotopes of an element as found in nature. ... Half-Life For a quantity subject to exponential decay, the half-life is the time required for the quantity to fall to half of its initial value. ... Radioactive decay is the process in which an unstable atomic nucleus loses energy by emitting radiation in the form of particles or electromagnetic waves. ... The decay energy is the energy released by a nuclear decay. ... The electronvolt (symbol eV) is a unit of energy. ... In nuclear physics, a decay product, also known as a daughter product, is a nuclide resulting from the radioactive decay of a parent or precursor nuclide. ... A Synthetic radioisotope is a radionuclide that is not found in nature: no natural process or mechanism exists which produces it, or it is so unstable that it decays away in a very short period of time. ... Look up day in Wiktionary, the free dictionary. ... Electron capture is a decay mode for isotopes that will occur when there are too many protons in the nucleus of an atom, and there isnt enough energy to emit a positron; however, it continues to be a viable decay mode for radioactive isotopes that can decay by positron... General Name, Symbol, Number rubidium, Rb, 37 Chemical series alkali metals Group, Period, Block 1, 5, s Appearance grey white Atomic mass 85. ... A Synthetic radioisotope is a radionuclide that is not found in nature: no natural process or mechanism exists which produces it, or it is so unstable that it decays away in a very short period of time. ... General Name, Symbol, Number rubidium, Rb, 37 Chemical series alkali metals Group, Period, Block 1, 5, s Appearance grey white Atomic mass 85. ... Positron emission is a type of beta decay, sometimes referred to as beta plus (β+). In beta plus decay, a proton is converted to a neutron via the weak nuclear force and a beta plus particle (a positron) and a neutrino are emitted. ... General Name, Symbol, Number rubidium, Rb, 37 Chemical series alkali metals Group, Period, Block 1, 5, s Appearance grey white Atomic mass 85. ... This article is about electromagnetic radiation. ... Stable isotopes are chemical isotopes that are not radioactive. ... This article or section does not adequately cite its references or sources. ... A Synthetic radioisotope is a radionuclide that is not found in nature: no natural process or mechanism exists which produces it, or it is so unstable that it decays away in a very short period of time. ... General Name, Symbol, Number rubidium, Rb, 37 Chemical series alkali metals Group, Period, Block 1, 5, s Appearance grey white Atomic mass 85. ... Delayed nuclear radiation can occur in a nuclear decay. ... Stable isotopes are chemical isotopes that are not radioactive. ... This article or section does not adequately cite its references or sources. ... Stable isotopes are chemical isotopes that are not radioactive. ... This article or section does not adequately cite its references or sources. ... Stable isotopes are chemical isotopes that are not radioactive. ... This article or section does not adequately cite its references or sources. ... A Synthetic radioisotope is a radionuclide that is not found in nature: no natural process or mechanism exists which produces it, or it is so unstable that it decays away in a very short period of time. ... General Name, Symbol, Number rubidium, Rb, 37 Chemical series alkali metals Group, Period, Block 1, 5, s Appearance grey white Atomic mass 85. ... In nuclear physics, beta decay (sometimes called neutron decay) is a type of radioactive decay in which a beta particle (an electron or a positron) is emitted. ... General Name, Symbol, Number yttrium, Y, 39 Chemical series transition metals Group, Period, Block 3, 5, d Appearance silvery white Atomic mass 88. ... A Synthetic radioisotope is a radionuclide that is not found in nature: no natural process or mechanism exists which produces it, or it is so unstable that it decays away in a very short period of time. ... A year (from Old English gÄ“r) is the time between two recurrences of an event related to the orbit of the Earth around the Sun. ... General Name, Symbol, Number yttrium, Y, 39 Chemical series transition metals Group, Period, Block 3, 5, d Appearance silvery white Atomic mass 88. ... Recommended values for many properties of the elements, together with various references, are collected on these data pages. ... Articles with similar titles include the NATO phonetic alphabet, which has also informally been called the “International Phonetic Alphabet”. For information on how to read IPA transcriptions of English words, see IPA chart for English. ... The periodic table of the chemical elements A chemical element, or element, is a type of atom that is defined by its atomic number; that is, by the number of protons in its nucleus. ... “The Periodic Table” redirects here. ... See also: List of elements by atomic number In chemistry and physics, the atomic number (also known as the proton number) is the number of protons found in the nucleus of an atom. ... The alkaline earth metals are the series of elements in Group 2 (IUPAC style) of the periodic table: beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba) and radium (Ra) (not always considered due to its radioactivity and very short half-life). ... Celestine or celestite[1] (SrSO4) is a mineral consisting of strontium sulfate. ... A sample of strontianite Strontianite (SrCO3) is a mineral consisting of strontium carbonate, named after the village of Strontian, Lochaber, Scotland, where it was first discovered. ... General Name, Symbol, Number Strontium, Sr, 38 Series Alkaline earth metal Group, Period, Block 2 (IIA), 5, s Density, Hardness 2630 kg/m3, 1. ... For other uses, see Isotope (disambiguation). ... Radioactive decay is the set of various processes by which unstable atomic nuclei (nuclides) emit subatomic particles. ... Fallout is the residual radiation hazard from a nuclear explosion, so named because it falls out of the atmosphere into which it is spread during the explosion. ... Half-Life For a quantity subject to exponential decay, the half-life is the time required for the quantity to fall to half of its initial value. ...

Contents

Notable characteristics

Due to its extreme reactivity to air, this element occurs naturally only in compounds with other elements, as in the minerals strontianite and celestite.


Strontium is a bright silvery metal that is softer than calcium and even more reactive in water, which strontium decomposes on contact with to produce strontium hydroxide and hydrogen gas. It burns in air to produce both strontium oxide and strontium nitride, but since it does not react with nitrogen below 380°C it will only form the oxide spontaneously at room temperature. It should be kept under kerosene to prevent oxidation; freshly exposed strontium metal rapidly turns a yellowish color with the formation of the oxide. Finely powdered strontium metal will ignite spontaneously in air. Volatile strontium salts impart a crimson color to flames, and these salts are used in pyrotechnics and in the production of flares. Natural strontium is a mixture of four stable isotopes. For other uses, see Calcium (disambiguation). ... Impact from a water drop causes an upward rebound jet surrounded by circular capillary waves. ... // Preparation Uses Used chiefly in the refining of beet sugar. ... General Name, Symbol, Number hydrogen, H, 1 Chemical series nonmetals Group, Period, Block 1, 1, s Appearance colorless Atomic mass 1. ... Strontium Oxide SrO is formed when strontium reacts with oxygen. ... Strontium Nitride Sr3N2 is produced by burning strontium metal in air or in Nitrogen. ... General Name, symbol, number nitrogen, N, 7 Chemical series nonmetals Group, period, block 15, 2, p Appearance colorless gas Standard atomic weight 14. ... Kerosene or kerosine, also called paraffin oil or paraffin in British usage (not to be confused with the waxy solid also called paraffin wax or just paraffin) is a flammable hydrocarbon liquid. ... The most fundamental reactions in chemistry are the redox processes. ... A yellow Tulip. ... For other uses, see Red (disambiguation). ... For other uses, see Fire (disambiguation). ... The word pyrotechnic (literally meaning fire technology) refers to any chemical explosive device, but especially fireworks. ... A World War I-era parachute flare dropped from aircraft for illumination. ... For other uses, see Isotope (disambiguation). ...


Applications

As a pure metal strontium is being used in strontium 90%-aluminium 10% alloys of an eutectic composition for the modification of aluminium-silicon casting alloys. The primary use for strontium compounds is in glass for color television cathode ray tubes to prevent X-ray emission. An alloy is a homogeneous mixture of two or more elements, at least one of which is a metal, and where the resulting material has metallic properties. ... A eutectic or eutectic mixture is a mixture of two or more elements which has a lower melting point than any of its constituents. ... This article is about the material. ... Color is an important part of the visual arts. ... Cathode ray tube employing electromagnetic focus and deflection Cutaway rendering of a color CRT: 1. ... In the NATO phonetic alphabet, X-ray represents the letter X. An X-ray picture (radiograph) taken by Röntgen An X-ray is a form of electromagnetic radiation with a wavelength approximately in the range of 5 pm to 10 nanometers (corresponding to frequencies in the range 30 PHz...


Other uses:

  • 89Sr is the active ingredient in Metastron, a radiopharmaceutical used for bone pain secondary to metastatic prostate cancer. The strontium acts like calcium and is preferentially incorporated into bone at sites of increased osteogenesis. This localization focuses the radiation exposure on the cancerous lesion.
  • 90Sr has been used as a power source for radioisotope thermoelectric generators (RTGs). 90Sr produces about 0.93 watts of heat per gram (it is lower for the grade of 90Sr used in RTGs, which is strontium fluoride).[1] However, 90Sr has a lifetime approximately 3 times shorter and has a lower density than 238Pu, another RTG fuel. The main advantage of 90Sr is that it is cheaper than 238Pu and is found in nuclear waste.
  • 90Sr is also used in cancer therapy. Its beta emission and long half-life is ideal for superficial radiotherapy.
  • Strontium is one of the constituents of AJ62 alloy, a durable magnesium alloy used in car and motorcycle engines by BMW.

87Sr/86Sr ratios are commonly used to determine the likely provenance areas of sediment in natural systems, especially in marine and fluvial environments. Dasch (1969) showed that surface sediments of the deep Atlantic displayed 87Sr/86Sr ratios that could be regarded as bulk averages of the 87Sr/86Sr ratios of geological terranes from adjacent landmasses. A good example of a fluvial system to which Sr isotope ratio studies have been frequently employed is the River Nile (Krom et al, 1999; Krom et al, 2002; Talbot et al. 2000). Due to the vastly differing ages of the rocks that constitute the majority of the Blue and White Nile catchment areas the changing provenance of sediment reaching the River Nile delta, and East Mediterranean Sea beyond, can be discerned through Sr isotopic studies. This information is useful as it can elicit information regarding palaeoclimate change. General Name, Symbol, Number Strontium, Sr, 38 Series Alkaline earth metal Group, Period, Block 2 (IIA), 5, s Density, Hardness 2630 kg/m3, 1. ... A radiopharmaceutical is a radioactive pharmaceutical. ... Metastasis (Greek: change of the state) is the spread of cancer from its primary site to other places in the body. ... Prostate cancer is a disease in which cancer develops in the prostate, a gland in the male reproductive system. ... For other uses, see Calcium (disambiguation). ... Osteogenesis imperfecta (OI), commonly known as brittle bone disease, is a group of genetic bone disorders. ... General Name, Symbol, Number Strontium, Sr, 38 Series Alkaline earth metal Group, Period, Block 2 (IIA), 5, s Density, Hardness 2630 kg/m3, 1. ... // A radioisotope thermoelectric generator (RTG) is a simple electrical generator which obtains its power from radioactive decay. ... Strontium fluoride, SrF2, is a compound of strontium and fluorine. ... Plutonium 238, is an isotope of plutonium with a half-life of 86. ... Political Punk band from Victorville, Ca WWW.MYSPACE.COM/NUCLEARWASTEX ... Cancer is a class of diseases or disorders characterized by uncontrolled division of cells and the ability of these to spread, either by direct growth into adjacent tissue through invasion, or by implantation into distant sites by metastasis (where cancer cells are transported through the bloodstream or lymphatic system). ... Radiation therapy (or radiotherapy) is the medical use of ionizing radiation as part of cancer treatment to control malignant cells (not to be confused with radiology, the use of radiation in medical imaging and diagnosis). ... For other uses, see BMW (disambiguation). ...


Compounds

Ferrites are ferromagnetic ceramic materials, compounds of iron, boron and barium or strontium or molybdenum. ... General Name, symbol, number zinc, Zn, 30 Chemical series transition metals Group, period, block 12, 4, d Appearance bluish pale gray Standard atomic weight 65. ... Strontium titanate is an oxide of strontium and titanium with the chemical formula SrTiO3. ... The refractive index (or index of refraction) of a medium is a measure for how much the speed of light (or other waves such as sound waves) is reduced inside the medium. ... In optics, dispersion is a phenomenon that causes the separation of a wave into spectral components with different frequencies, due to a dependence of the waves speed on its frequency. ... This article is about the gemstone. ... A selection of gemstone pebbles made by tumbling rough rock with abrasive grit, in a rotating drum. ... Due to its low cost and close visual likeness to diamond, cubic zirconia has remained the most gemologically and economically important diamond simulant since 1976. ... Flash point Not applicable Except where noted otherwise, data are given for materials in their standard state (at 25 Â°C, 100 kPa) Infobox disclaimer and references Strontium carbonate (SrCO3) is a the carbonate salt of strontium that has the appearance of a white or grey powder. ... Strontium nitrate is the chemical compound with the formula Sr(NO3)2. ... Celestite (SrSO4) is a mineral consisting of strontium sulfate. ... It has been suggested that this article or section be merged into Fireworks. ... Strontium aluminate (SRA, SrAl, SrAl2O4) is a solid odorless nonflammable pale yellow powder, heavier than water. ... Green screen A phosphor is a substance that exhibits the phenomenon of phosphorescence (sustained glowing after exposure to light or energised particles such as electrons). ... Phosphorescent powder under visible light, ultraviolet light, and total darkness. ... Strontium chloride (SrCl2) is a salt of strontium and chlorine. ... Modern toothpaste gel Toothpaste is a paste or gel dentifrice used to clean and improve the aesthetic appearance and health of teeth. ... Strontium Oxide SrO is formed when strontium reacts with oxygen. ... Unfired green ware pottery on a traditional drying rack at Conner Prairie living history museum. ... Composite body, painted, and glazed bottle. ... Strontium ranelate is a medication for osteoporosis marketed as Protelos or Protos by Servier. ...

History

The mineral strontianite is named after the Scottish village of Strontian, having been discovered in the lead mines there in 1787.[2] Adair Crawford recognized it as differing from other barium minerals in 1790. Strontium itself was discovered in 1798 by Thomas Charles Hope, and metallic strontium was first isolated by Sir Humphry Davy in 1808 using electrolysis. A mineral is a naturally occurring substance formed through geological processes that has a characteristic chemical composition, a highly ordered atomic structure and specific physical properties. ... A sample of strontianite Strontianite (SrCO3) is a mineral consisting of strontium carbonate, named after the village of Strontian, Lochaber, Scotland, where it was first discovered. ... This article is about the country. ... [1]Strontian is a village in Ardgour at the head of Loch Sunart, in the Scottish Highlands. ... Year 1787 was a common year starting on Monday (see link for calendar). ... Adair Crawford (1748-July 1795), a Scots-Irish chemist, was responsible for discovering the element strontium in 1790 along with William Cruickshank. ... For other uses, see Barium (disambiguation). ... Year 1790 (MDCCXC) was a common year starting on Friday (link will display the full calendar) of the Gregorian calendar (or a common year starting on Monday of the 11-day slower Julian calendar). ... Year 1798 (MDCCXCVIII) was a common year starting on Monday (link will display the full calendar) of the Gregorian calendar (or a common year starting on Friday of the 11-day slower Julian calendar). ... In 1795, Joseph Black selected Thomas Charles Hope (1766-1844) as his assistant and eventual successor to the professorship of Chemistry at the University of Edinburgh. ... Sir Humphry Davy, 1st Baronet, FRS (17 December 1778 – 29 May 1829) was a British chemist and physicist. ... Year 1808 (MDCCCVIII) was a leap year starting on Friday (link will display the full calendar) of the Gregorian calendar (or a leap year starting on Wednesday of the 12-day slower Julian calendar). ... This article is about the chemical process. ...


Strontium was among the radioactive materials released by the 1957 Windscale fire. Year 1957 (MCMLVII) was a common year starting on Tuesday (link displays the 1957 Gregorian calendar). ... On October 10, 1957, the graphite core of a British nuclear reactor at Windscale, Cumbria, caught fire, releasing substantial amounts of radioactive contamination into the surrounding area. ...


Occurrence

Strontium output in 2005
Strontium output in 2005

In 2005, China was the top producer of strontium with almost two-thirds world share followed by Spain and Mexico, reports the British Geological Survey. Image File history File links Size of this preview: 800 × 351 pixelsFull resolution (1425 × 625 pixel, file size: 57 KB, MIME type: image/png)This bubble map shows the global distribution of strontium output in 2005 as a percentage of the top producer (China - 700,000 tonnes). ... Image File history File links Size of this preview: 800 × 351 pixelsFull resolution (1425 × 625 pixel, file size: 57 KB, MIME type: image/png)This bubble map shows the global distribution of strontium output in 2005 as a percentage of the top producer (China - 700,000 tonnes). ... The British Geological Survey is a publicly-funded body which aims to advance geoscientific knowledge of the United Kingdom landmass and its continental shelf by means of systematic surveying, monitoring and research. ...


Strontium commonly occurs in nature, the 15th most abundant element on earth, averaging 0.034% of all igneous rock and is found chiefly as the form of the sulfate mineral celestite (SrSO4) and the carbonate strontianite (SrCO3). Of the two, celestite occurs much more frequently in sedimentary deposits of sufficient size to make development of mining facilities attractive. Strontianite would be the more useful of the two common minerals because strontium is used most often in the carbonate form, but few deposits have been discovered that are suitable for development. The metal can be prepared by electrolysis of melted strontium chloride mixed with potassium chloride: In inorganic chemistry, a sulfate (IUPAC-recommended spelling; also sulphate in British English) is a salt of sulfuric acid. ... A mineral is a naturally occurring substance formed through geological processes that has a characteristic chemical composition, a highly ordered atomic structure and specific physical properties. ... Clear grey-blue celestite crystal crust from Madagascar Celestine from the Machow Mine, Poland. ... In organic chemistry, a carbonate is a salt of carbonic acid. ... A sample of strontianite Strontianite (SrCO3) is a mineral consisting of strontium carbonate, named after the village of Strontian, Lochaber, Scotland, where it was first discovered. ... This article does not cite any references or sources. ... This article is about the chemical process. ... Strontium chloride (SrCl2) is a salt of strontium and chlorine. ... The chemical compound potassium chloride (KCl) is a metal halide composed of potassium and chlorine. ...

Sr2+ + 2 e- → Sr
2 Cl- → Cl2 (g) + 2 e-

Alternatively it is made by reducing strontium oxide with aluminium in a vacuum at a temperature at which strontium distills off. Three allotropes of the metal exist, with transition points at 235 and 540 °C. The largest commercially exploited deposits are found in England. For other uses, see Gas (disambiguation). ... An oxide is a chemical compound containing an oxygen atom and other elements. ... General Name, symbol, number aluminium, Al, 13 Chemical series poor metals Group, period, block 13, 3, p Appearance gray Standard atomic weight 26. ... Look up Vacuum in Wiktionary, the free dictionary. ... יחכיטכיגיגיוגקאטגקעיגקDistillation is a method of separating chemical substances based on differences in their volatilities in a boiling liquid mixture. ... Allotropy (Gr. ... In the field of fluid dynamics the point at which the boundary layer changes from laminar to turbulent is called the transition point. ... For other uses, see England (disambiguation). ...


See also strontium minerals.


Isotopes

Main article: Isotopes of strontium

The alkali earth metal strontium has four stable, naturally occurring isotopes: 84Sr (0.56%), 86Sr (9.86%), 87Sr (7.0%) and 88Sr (82.58%). Only 87Sr is radiogenic; it is produced by decay from the radioactive alkali metal 87Rb, which has a half-life of 4.88 × 1010 years. Thus, there are two sources of 87Sr in any material: that formed during primordial nucleo-synthesis along with 84Sr, 86Sr and 88Sr, as well as that formed by radioactive decay of 87Rb. The ratio 87Sr/86Sr is the parameter typically reported in geologic investigations; ratios in minerals and rocks have values ranging from about 0.7 to greater than 4.0. Because strontium has an atomic radius similar to that of calcium, it readily substitutes for Ca in minerals. Strontium (Sr) Standard atomic mass: 87. ... The alkaline earth metals are the series of elements in Group 2 of the periodic table: beryllium, magnesium, calcium, strontium, barium and radium (not always considered due to its very short half-life). ... For other uses, see Isotope (disambiguation). ... A radiogenic nuclide is one that is produced by a process of radioactive decay. ... Radioactive decay is the set of various processes by which unstable atomic nuclei (nuclides) emit subatomic particles. ... General Name, Symbol, Number rubidium, Rb, 37 Chemical series alkali metals Group, Period, Block 1, 5, s Appearance grey white Atomic mass 85. ... Half-Life For a quantity subject to exponential decay, the half-life is the time required for the quantity to fall to half of its initial value. ... This article includes a list of works cited but its sources remain unclear because it lacks in-text citations. ... For other uses, see Rock (disambiguation). ... Atomic radius: Ionic radius Covalent radius Metallic radius van der Waals radius edit Atomic radius, and more generally the size of an atom, is not a precisely defined physical quantity, nor is it constant in all circumstances. ... For other uses, see Calcium (disambiguation). ... A mineral is a naturally occurring substance formed through geological processes that has a characteristic chemical composition, a highly ordered atomic structure and specific physical properties. ...


Sixteen unstable isotopes are known to exist. Of greatest importance is 90Sr with a half-life of 28.78 years. It is a by-product of nuclear fission which is found in nuclear fallout and presents a health problem since it substitutes for calcium in bone, preventing expulsion from the body. This isotope is one of the best long-lived high-energy beta emitters known, and is used in SNAP (Systems for Nuclear Auxiliary Power) devices. These devices hold promise for use in spacecraft, remote weather stations, navigational buoys, etc, where a lightweight, long-lived, nuclear-electric power source is required. The 1986 Chernobyl nuclear accident contaminated a vast area with 90Sr. Half-Life For a quantity subject to exponential decay, the half-life is the time required for the quantity to fall to half of its initial value. ... An induced nuclear fission event. ... Fallout is the residual radiation hazard from a nuclear explosion, so named because it falls out of the atmosphere into which it is spread during the explosion. ... This article is about the skeletal organs. ... Beta particles are high-energy electrons emitted by certain types of radioactive nuclei such as potassium-40. ... // A radioisotope thermoelectric generator (RTG) is a simple electrical generator which obtains its power from radioactive decay. ... The Space Shuttle Discovery as seen from the International Space Station. ... The nuclear power plant at Chernobyl prior to the completion of the sarcophagus. ...


Precautions

In its pure form strontium is extremely reactive with air and spontaneously combusts. It is therefore considered to be a fire hazard. Gas stoves are often considered a fire hazard A fire hazard is any situation in which there is a greater than normal risk of harm to people or property due to fire. ...


Effect on the human body

The human body absorbs strontium as if it were calcium. Due to the elements being sufficiently similar chemically, the stable forms of strontium do not pose a significant health threat, but the radioactive 90Sr can lead to various bone disorders and diseases, including bone cancer. The strontium unit is used in measuring radioactivity from absorbed 90Sr. This article is about modern humans. ... For other uses, see Calcium (disambiguation). ... This article is about the skeletal organs. ... This article is about the medical term. ... A sarcoma is a cancer of the bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue. ... The strontium unit is a unit used to measure the amount of radioactivity from strontium-90, a chemical found in nuclear fallout, in a subjects body; as the human body mistakes the substance for calcium and incorporates it into the skeleton, its presence is very common. ...


An innovative drug made by combining strontium with ranelic acid has aided in bone growth, boosted bone density and lessened vetrebral, peripheral and hip fractures.[3] [4] Women receiving the drug showed a 12.7% increase in bone density. Women receiving a placebo had a 1.6% decrease. Half the increase in bone density (measured by x-ray densitometry) is attributed to the higher atomic weight of Sr compared with calcium, whereas the other half a true increase in bone mass. It means that strontium ranelate creates new and strong bone. Strontium ranelate (marketed under the trade names Protelos, Osseor, Protos, Bivalos, Protaxos, Ossum) is registered for treatment of osteoporosis in many countries all over the world. Strontium ranelate has been shown to strengthen bones, according presentations given the IOF World Congress on Osteoporosis, in June of 2006. It also reduced bone resorbtion. To meet Wikipedias quality standards, this article or section may require cleanup. ... This article is about the skeletal organs. ... A fractured bone in a living person is typically treated by restoring the fractured pieces of bone to their natural positions (if necessary), and maintaining those positions while the bone heals. ...


Strontium ranelate is registered as a prescription drug in Europe and many countries worldwide. It needs to be prescribed by a doctor, delivered by a pharmacist and requires a strict medical supervision. Currently, (early 2007) it is not available in Canada or the United States.


Several other salts of strontium such as strontium citrate or strontium carbonate are often presented as natural therapies and sold at a dose that is several hundred times higher than the usual strontium intake. Despite the lack of strontium deficit referenced in the medical literature and the lack of information about possible toxicity of strontium supplementation, such compounds can still be sold in the United States under the Dietary Supplements Health and Education Act of 1994.


However, their long-term safety and efficacy have never been evaluated on humans using large-scale medical trials. Such compounds should not be administered to humans before further studies are conducted.


An attempt was made in 1968 to poison Alexander Dubček with Sr-90, but it failed. Year 1968 (MCMLXVIII) was a leap year starting on Monday (link will display full calendar) of the Gregorian calendar. ... Alexander Dubček (November 27, 1921 – November 7, 1992) was a Slovak politician and briefly leader of Czechoslovakia (1968-1969), famous for his attempt to reform the Communist regime (Prague Spring). ...


See also

  • Strontium compounds

References

  1. ^ http://www.qrg.northwestern.edu/projects/vss/docs/Power/3-what-are-the-fuels-for-rtgs.html
  2. ^ Murray, W.H. (1977) The Companion Guide to the West Highlands of Scotland. London. Collins
  3. ^ Meunier PJ, Roux C, Seeman E et al. (2004). "effects of strontium ranelate on the risk of vertebral fracture in women with postmenopausal osteoporosis.". New England Journal of Medicine 350: 459-468. PMID 14749454. 
  4. ^ Reginster JY, Seeman E, De Vernejoul MC et al. (2005). "Strontium ranelate reduces the risk of nonvertebral fractures in postmenopausal women with osteoporosis: treatment of peripheral osteoporosis (TROPOS) study". J Clin Metab. 90: 2816-2822. PMID 15728210. 

Dasch, J. (1969). Strontium isotopes in weathering profiles, deep-sea sediments, and sedimentary rocks. Geochimica et Cosmochimica Acta, Vol. 33, pp. 1521-1552. Krom et al. (1999). The characterisation of Saharan Dusts and Nile particulate matter in surface sediments from the Levantine basin using Sr isotopes. Marine Geology, Vol. 155, pp. 319-330. Krom et al. (2002). Nile River sediment fluctuations over the past 7000 yr and their key role in sapropel development. Geology, Vol. 30, pp. 71-74. Talbot et al., (2000). Strontium isotope evidence for late Pleistocene reestablishment of an integrated Nile drainage network. Geology, Vol. 28, pp. 343-346. is the 217th day of the year (218th in leap years) in the Gregorian calendar. ... Year 2005 (MMV) was a common year starting on Saturday (link displays full calendar) of the Gregorian calendar. ...


  Results from FactBites:
 
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Strontium does not occur as the free element.
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Strontium metal is available commercially and there is no need to make it in the laboratory.
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Celestite and strontianite are the chief ores of strontium.
Principal uses of strontium compounds are in pyrotechnics (chiefly the nitrate) and in greases (the hydroxide).
Strontium was first recognized as distinct from barium in 1790 by A. Crawford in a sample of its carbonate from a mine near Strontian, Scotland; his finding was later confirmed by T. Hope, M. Klaproth, and others.
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