The phosphate or orthophosphate ion [PO 4]3− is derived from phosphoric acid by the removal of three protonsH+ . Removal of one proton gives the dihydrogen phosphate ion [H 2PO 4]− while removal of two protons gives the hydrogen phosphate ion [HPO 4]2− . These names are also used for salts of those anions, such as ammonium dihydrogen phosphate and trisodium phosphate.
In organic chemistry, phosphate or orthophosphate is an organophosphate, an ester of orthophosphoric acid of the form PO 4RR′R″ where one or more hydrogen atoms are replaced by organic groups. An example is trimethyl phosphate, (CH 3) 3PO 4. The term also refers to the trivalent functional group OP(O-) 3 in such esters. Phosphates may contain sulfur in place of one or more oxygen atoms (thiophosphates and organothiophosphates).
The phosphate ion has a molar mass of 94.97 g/mol, and consists of a central phosphorus atom surrounded by four oxygen atoms in a tetrahedral arrangement. It is the conjugate base of the hydrogen phosphate ion H(PO 4)2− , which in turn is the conjugate base of the dihydrogen phosphate ion H 2(PO 4)− , which in turn is the conjugate base of orthophosphoric acid, H 3PO 4.
Many phosphates are soluble in water at standard temperature and pressure. The sodium, potassium, rubidium, caesium, and ammonium phosphates are all water-soluble. Most other phosphates are only slightly soluble or are insoluble in water. As a rule, the hydrogen and dihydrogen phosphates are slightly more soluble than the corresponding phosphates.
The pKa values are the pH values where the concentration of each species is equal to that of its conjugate bases. At pH 1 or lower, the phosphoric acid is practically undissociated. Around pH 4.7 (mid-way between the first two pKa values) the dihydrogen phosphate ion, [H 2PO 4]− , is practically the only species present. Around pH 9.8 (mid-way between the second and third pKa values) the monohydrogen phosphate ion, [HPO 4]2− , is the only species present. At pH 13 or higher, the acid is completely dissociated as the phosphate ion, (PO 4)3− .
This means that salts of the mono- and di-phosphate ions can be selectively crystallised from aqueous solution by setting the pH value to either 4.7 or 9.8.
In effect, H 3PO 4, H 2(PO 4)− and H(PO 4)2− behave as separate weak acids because the successive pKa differ by more than 4.
Phosphate can form many polymeric ions such as pyrophosphate, (P 2O 7)4− , and triphosphate, (P 3O 10)5− . The various metaphosphate ions (which are usually long linear polymers) have an empirical formula of (PO 3)− and are found in many compounds.
Biochemistry of phosphates
In biological systems, phosphorus can be found as free phosphate anions in solution (inorganic phosphate) or bound to organic molecules as various organophosphates.
Inorganic phosphate is generally denoted Pi and at physiological (homeostatic) pH primarily consists of a mixture of [HPO 4]2− and [H 2PO 4]− ions. At a neutral pH, as in the cytosol (pH = 7.0), the concentrations of the orthophoshoric acid and its three anions have the ratios
Thus, only [H 2PO 4]− and [HPO 4]2− ions are present in significant amounts in the cytosol (62% [H 2PO 4]− , 38% [HPO 4]2− ). In extracellular fluid (pH = 7.4), this proportion is inverted (61% [HPO 4]2− , 39% [H 2PO 4]− ).
Inorganic phosphate can also be present as pyrophosphate anions [P 2O 7]4− , which give orthophosphate by hydrolysis:
An important occurrence of phosphates in biological systems is as the structural material of bone and teeth. These structures are made of crystalline calcium phosphate in the form of hydroxyapatite. The hard dense enamel of mammalian teeth may contain fluoroapatite, a hydroxy calcium phosphate where some of the hydroxyl groups have been replaced by fluoride ions.
Medical and biological research uses
Phosphates are medicinal salts of phosphorus. Some phosphates, which help cure many urinary tract infections, are used to make urine more acidic. To avoid the development of calcium stones in the urinary tract, some phosphates are used.[5] For patients who are unable to get enough phosphorus in their daily diet, phosphates are used as dietary supplements, usually because of certain disorders or diseases.[5] Injectable phosphates can only be handled by qualified health care providers.[5]
Plant metabolism
Plants take up phosphorus through several pathways: the arbuscular mycorrhizal pathway and the direct uptake pathway.
Hyperphosphatemia, or a high blood level of phosphates, is associated with elevated mortality in the general population. The most common cause of hyperphosphatemia in people, dogs, and cats is kidney failure. In cases of hyperphosphatemia, limiting consumption of phosphate-rich foods, such as some meats and dairy items and foods with a high phosphate-to-protein ratio, such as soft drinks, fast food, processed foods, condiments, and other products containing phosphate-salt additives is advised.[6]
Phosphates are the naturally occurring form of the element phosphorus, found in many phosphate minerals. In mineralogy and geology, phosphate refers to a rock or ore containing phosphate ions. Inorganic phosphates are mined to obtain phosphorus for use in agriculture and industry.[2]
The largest global producer and exporter of phosphates is Morocco. Within North America, the largest deposits lie in the Bone Valley region of central Florida, the Soda Springs region of southeastern Idaho, and the coast of North Carolina. Smaller deposits are located in Montana, Tennessee, Georgia, and South Carolina. The small island nation of Nauru and its neighbor Banaba Island, which used to have massive phosphate deposits of the best quality, have been mined excessively. Rock phosphate can also be found in Egypt, Israel, Palestine, Western Sahara, Navassa Island, Tunisia, Togo, and Jordan, countries that have large phosphate-mining industries.
In 2007, at the current rate of consumption, the supply of phosphorus was estimated to run out in 345 years.[8] However, some scientists thought that a "peak phosphorus" would occur in 30 years and Dana Cordell from Institute for Sustainable Futures said that at "current rates, reserves will be depleted in the next 50 to 100 years".[9] Reserves refer to the amount assumed recoverable at current market prices. In 2012 the USGS estimated world reserves at 71 billion tons, while 0.19 billion tons were mined globally in 2011.[10] Phosphorus comprises 0.1% by mass of the average rock[11] (while, for perspective, its typical concentration in vegetation is 0.03% to 0.2%),[12] and consequently there are quadrillions of tons of phosphorus in Earth's 3×1019-ton crust,[13] albeit at predominantly lower concentration than the deposits counted as reserves, which are inventoried and cheaper to extract. If it is assumed that the phosphate minerals in phosphate rock are mainly hydroxyapatite and fluoroapatite, phosphate minerals contain roughly 18.5% phosphorus by weight. If phosphate rock contains around 20% of these minerals, the average phosphate rock has roughly 3.7% phosphorus by weight.
Some phosphate rock deposits, such as Mulberry in Florida,[14] are notable for their inclusion of significant quantities of radioactive uranium isotopes. This is a concern because radioactivity can be released into surface waters[15] from application of the resulting phosphate fertilizer.
In December 2012, Cominco Resources announced an updated JORC compliant resource of their Hinda project in Congo-Brazzaville of 531 million tons, making it the largest measured and indicated phosphate deposit in the world.[16]
Around 2018, Norway discovered phosphate deposits almost equal to those in the rest of Earth combined.[17][18]
In July 2022 China announced quotas on phosphate exportation.[19]
The largest importers in millions of metric tons of phosphate are Brazil 3.2, India 2.9 and the USA 1.6.[20]
Mining
Phosphate imports/exports in 1937
The three principal phosphate producer countries (China, Morocco and the United States) account for about 70% of world production.
Production and global reserves of natural phosphate by country in 2019 (USGS, 2021)[21]
Sea surface phosphate from the World Ocean AtlasRelationship of phosphate to nitrate uptake for photosynthesis in various regions of the ocean. Note that nitrate is more often limiting than phosphate. See the Redfield ratio.
In ecological terms, because of its important role in biological systems, phosphate is a highly sought after resource. Once used, it is often a limiting nutrient in environments, and its availability may govern the rate of growth of organisms. This is generally true of freshwater environments, whereas nitrogen is more often the limiting nutrient in marine (seawater) environments. Addition of high levels of phosphate to environments and to micro-environments in which it is typically rare can have significant ecological consequences. For example, blooms in the populations of some organisms at the expense of others, and the collapse of populations deprived of resources such as oxygen (see eutrophication) can occur. In the context of pollution, phosphates are one component of total dissolved solids, a major indicator of water quality, but not all phosphorus is in a molecular form that algae can break down and consume.[22]
Calcium hydroxyapatite and calcite precipitates can be found around bacteria in alluvial topsoil.[23] As clay minerals promote biomineralization, the presence of bacteria and clay minerals resulted in calcium hydroxyapatite and calcite precipitates.[23]
Phosphate deposits can contain significant amounts of naturally occurring heavy metals. Mining operations processing phosphate rock can leave tailings piles containing elevated levels of cadmium, lead, nickel, copper, chromium, and uranium. Unless carefully managed, these waste products can leach heavy metals into groundwater or nearby estuaries. Uptake of these substances by plants and marine life can lead to concentration of toxic heavy metals in food products.[24]
^ ab"Phosphate Primer". Florida Industrial and Phosphate Research Institute. Florida Polytechnic University. Archived from the original on 29 August 2017. Retrieved 30 March 2018.
^Kipton J. Powell, Paul L. Brown, Robert H. Byrne, Tamás Gajda, Glenn Hefter, Staffan Sjöberg, Hans Wanner (2005): "Chemical speciation of environmentally significant heavy metals with inorganic ligands. Part 1: The Hg2+ , Cl−, OH−, CO2− 3, SO2− 4, and PO3− 4 aqueous systems". Pure and Applied Chemistry, volume 77, issue 4, pages 739–800. doi:10.1351/pac200577040739
^Hochanadel, Dave (December 10, 2010). "Limited amount of total phosphorus actually feeds algae, study finds". Lake Scientist. Retrieved June 10, 2012. [B]ioavailable phosphorus – phosphorus that can be utilized by plants and bacteria – is only a fraction of the total, according to Michael Brett, a UW engineering professor ...
^Gnandi, K.; Tchangbedjil, G.; Killil, K.; Babal, G.; Abbel, E. (March 2006). "The Impact of Phosphate Mine Tailings on the Bioaccumulation of Heavy Metals in Marine Fish and Crustaceans from the Coastal Zone of Togo". Mine Water and the Environment. 25 (1): 56–62. doi:10.1007/s10230-006-0108-4. S2CID129497587.
External links
Wikimedia Commons has media related to Phosphates.
US Minerals Databrowser provides data graphics covering consumption, production, imports, exports and price for phosphate and 86 other minerals
أورسولا كوربيرو Úrsula Corberó أورسولا كوربيرو أثناء مشاركتها في حفل جوائز جويا عام 2018 معلومات شخصية اسم الولادة أورسولا كوربيرو ديلغادو الميلاد 11 أغسطس 1989 (العمر 34 سنة)برشلونة، إسبانيا الجنسية إسبانيا الطول 1.63 متر[1] الحياة العملية المهنة ممثلة، وممثلة أفلام، و…
2013 American filmSnake & MongooseTheatrical release posterDirected byWayne HollowayWritten by Alan Paradise Wayne Holloway Produced by Robin Broidy Stephen Nemeth Starring Jesse Williams Richard Blake Ashley Hinshaw Kim Shaw Tim Blake Nelson Fred Dryer Noah Wyle CinematographyJohn BaileyEdited by Richard Halsey Nicholas Wayman-Harris Music byGary BarloughProductioncompanies Entertainment Universe Rhino Films Distributed byRocky Mountain PicturesRelease date September 6, 2013 …
Cassaignes Blason Administration Pays France Région Occitanie Département Aude Arrondissement Limoux Intercommunalité Communauté de communes du Limouxin Maire Mandat Serge Ferrié 2020-2026 Code postal 11190 Code commune 11073 Démographie Gentilé Cassaignols Populationmunicipale 59 hab. (2020 ) Densité 16 hab./km2 Géographie Coordonnées 42° 56′ 48″ nord, 2° 18′ 00″ est Altitude Min. 252 mMax. 486 m Superficie 3,74 km2 Unit…
Este artículo trata sobre el salmo 94 según la numeración hebrea. Para el salmo número 94 según la numeración griega y latina, véase Salmo 95. Salmo 94 «Salmo 94» Salmo de David La Biblia de arte, que comprende el Antiguo y el Nuevo Testamento, con numerosas ilustraciones (1896)Catálogo SalmoTonalidad SalmoDetallesDedicatoria SalmoEstilo SalmoMovimientos Salmo[editar datos en Wikidata] El salmo 94 es, según la numeración hebrea, el nonagésimo cuarto salmo del Libro de…
Nigerian footballer This article is an orphan, as no other articles link to it. Please introduce links to this page from related articles; try the Find link tool for suggestions. (September 2018) Lucky OmeruoPersonal informationFull name Lucky OmeruoDate of birth (1995-09-15) 15 September 1995 (age 28)Place of birth Abuja, NigeriaHeight 1.81 m (5 ft 11 in)Position(s) ForwardTeam informationCurrent team City PiratesYouth career2009–2011 Heart FoundationSenior career*Years Te…
Defunct railway station Capital BeltwayCapital Beltway in 1979 as an Amtrak Metroliner arrives. Note the green Penn Central signage.General informationCoordinates38°57′19″N 76°51′57″W / 38.9554°N 76.8659°W / 38.9554; -76.8659Line(s)Northeast CorridorPlatforms2 side platformsHistoryOpenedMarch 16, 1970 (1970-03-16)ClosedOctober 30, 1983 (1983-10-30)Former services Preceding station Amtrak Following station Washington, D.C.Terminus …
Estonia na Letnich Igrzyskach Olimpijskich 1920 Kod MKOl EST Letnie Igrzyska Olimpijskie 1920Antwerpia Chorąży Harald Tammer Liczba zawodników 14 w 3 dyscyplinach MedalePozycja: 14. Złoto1 Srebro2 Brąz0 Razem3 Debiutującą Estonię na Letnich Igrzyskach Olimpijskich 1920 reprezentowało 14 sportowców, sami mężczyźni. Brali udział w 19 konkurencjach w 3 dyscyplinach. Zdobyli 3 medale, 1 w lekkoatletyce i 2 w podnoszeniu ciężarów. Medale Medal Zawodnik Dyscyplina Konkurencja Dat…
Potentilla tanacetifolia Klasifikasi ilmiah Kerajaan: Plantae (tanpa takson): Angiospermae (tanpa takson): Eudicots (tanpa takson): Rosids Ordo: Rosales Famili: Rosaceae Genus: Potentilla Spesies: Potentilla tanacetifolia Nama binomial Potentilla tanacetifoliaWilld. ex Schltdl. Potentilla tanacetifolia adalah spesies tumbuhan yang tergolong ke dalam famili Rosaceae. Spesies ini juga merupakan bagian dari ordo Rosales. Spesies Potentilla tanacetifolia sendiri merupakan bagian dari genus Potentill…
Artikel ini sebatang kara, artinya tidak ada artikel lain yang memiliki pranala balik ke halaman ini.Bantulah menambah pranala ke artikel ini dari artikel yang berhubungan atau coba peralatan pencari pranala.Tag ini diberikan pada November 2022. Hynd Bouhia adalah kelahiran Maroko dan peraih gelar Ph.D dari Harvard. Ia turut membantu bursa negaranya sekaligus sebagai penasihat Perdana Menteri bidang ekonomi pada tahun 2004. Bouhia pernah berada di garda terdepan dalam mengamankan investasi asing…
1998 United States Senate election in Arkansas ← 1992 November 3, 1998 2004 → Nominee Blanche Lincoln Fay Boozman Party Democratic Republican Popular vote 385,878 295,870 Percentage 55.07% 42.23% County resultsLincoln: 40–50% 50–60% 60–70% 70–80% 80–90%Boozman: 40–50% …
International non-governmental group HRW redirects here. For other uses, see HRW (disambiguation). Not to be confused with Bahrain Human Rights Watch Society or Human Rights Campaign. Human Rights WatchFounded1978; 45 years ago (1978) (as Helsinki Watch)TypeNon-profit, NGOFocusHuman rights, activismHeadquartersNew York City, U.S.Area served WorldwideProductNonprofit human rights advocacyKey peopleTirana Hassan(Executive Director)James F. Hoge Jr.(Chairman)Revenue $85.6 million …
Bronislovas PaukštysBorn(1897-02-15)15 February 1897Kurynė [lt], Suwałki Governorate, Congress PolandDied17 December 1966(1966-12-17) (aged 69)Kaunas, Lithuanian SSRNationalityLithuanianOccupationCatholic priestKnown forRescue of Jews during World War IIAwardsRighteous Among the Nations (1977) Life Saving Cross [lt] (1999) Bronislovas Bronius Paukštys (1897–1966) was a Lithuanian Roman Catholic priest who rescued around 120 Jewish children and 25 Jewish …
Universal banking group located in the Philippines Union Bank of the PhilippinesFormerlyUnion Savings and Mortgage BankTypePublicTraded asPSE: UBPIndustryFinance and InsuranceFoundedAugust 16, 1968; 55 years ago (1968-08-16) in Manila, PhilippinesHeadquartersUnionBank Plaza, Ortigas Center, Pasig, PhilippinesArea servedPhilippinesKey people Erramon I. Aboitiz (Chairman) Justo A. Ortiz (Vice Chairman) Edwin R. Bautista (President and CEO) ProductsDigital bankingConsumer ban…
Djamari ChaniagoKepala Staf Umum Tentara Nasional IndonesiaMasa jabatan8 Maret 2000 – 16 Maret 2004PendahuluSuaidi MarasabessyPenggantiWartoyoWakil Kepala Staf TNI Angkatan DaratMasa jabatan9 November 1999 – 1 Maret 2000PendahuluJohny LumintangPenggantiEndriartono SutartoPanglima Komando Cadangan Strategis Angkatan DaratMasa jabatan23 Mei 1998 – 24 November 1999PendahuluJohny LumintangPenggantiDjaja Suparman Informasi pribadiLahir8 April 1949 (umur 74)Padang…
لوحة فوياجر الذهبية مطلية بالذهب. الطلي بالذهب هو شكل خاص من أشكال الطلي الكهربائي يتم فيه وضع ترسيب طبقة رقيقة من الذهب على سطح سبيكة أو فلز آخر مثل النحاس أو الفضة (في حال طلي الفضة بالذهب نحصل على الفضة المذهبة). يمكن أجراء عملية الطلي بالذهب بوسائل أخرى غير الطلي الكهربائي…
دكتورة ليلى الصباغ أكاديمية، وكاتبة. معلومات شخصية تاريخ الميلاد 1924 الوفاة 1 فبراير 2013 (89 سنة)دمشق الجنسية سورية الديانة الإسلام عضوة في مجمع اللغة العربية بدمشق الحياة العملية التعلّم دكتوراه المهنة مديرة التجهيز الأولى للبنات,أستاذ جامعي اللغات العربية سبب الشهرة …
2019 Thai television series Theory of LoveThaiTheory of Love – ทฤษฎีจีบเธอ GenreRomantic comedyDramaCreated byGMMTVBased onTheory of Love (ทฤษฎีจีบเธอ)by JittiRainDirected byNuttapong MongkolsawasStarringAtthaphan PhunsawatJumpol AdulkittipornEnding themeพระเอกจำลอง (Fake Protagonist) by GetsunovaCountry of originThailandOriginal languageThaiNo. of episodes12ProductionRunning time48–62 minutesProduction companyGMMTVOriginal re…
1978 novel by Judy Blume Wifey First editionAuthorJudy BlumeCountryUnited StatesLanguageEnglishPublisherPutnamPublication date1978Media typePrintPages288 ppISBN0-399-12241-9OCLC3843199Dewey Decimal813/.5/4LC ClassPZ4.B65748 Wi 1978 PS3552.L843 Wifey is a 1978 American novel written by Judy Blume. Plot The story follows the life of bored 1970s New Jersey housewife, Sandy Pressman, who decides to reinvigorate her life by having an extramarital affair with an old high school boyfriend. Th…