Monopotassium phosphate can exist in several polymorphs. At room temperature it forms paraelectric crystals with tetragonal symmetry. Upon cooling to −150 °C (−238 °F) it transforms to a ferroelectric phase of orthorhombic symmetry, and the transition temperature shifts up to −50 °C (−58 °F) when hydrogen is replaced by deuterium.[8] Heating to 190 °C (374 °F) changes its structure to monoclinic.[9] When heated further, MKP decomposes, by loss of water, to potassium metaphosphate, KPO 3, at 400 °C (752 °F).
Fertilizer-grade MKP powder contains the equivalent of 52% P 2O 5 and 34% K 2O, and is labeled NPK0-52-34. MKP powder is often used as a nutrient source in the greenhouse trade and in hydroponics.
Also, to be noted is KD*P, potassium dideuterium phosphate, with slightly different properties. Highly deuterated KDP is used in nonlinear frequency conversion of laser light instead of protonated (regular) KDP due to the fact that the replacement of protons with deuterons in the crystal shifts the third overtone of the strong OH molecular stretch to longer wavelengths, moving it mostly out of the range of the fundamental line at approximately 1064 nm of neodymium-based lasers. Regular KDP has absorbances at this wavelength of approximately 4.7–6.3% per cm of thickness while highly deuterated KDP has absorbances of typically less than 0.8% per cm.
^ ab"Commission Regulation (EU) No 231/2012 of 9 March 2012 laying down specifications for food additives listed in Annexes II and III to Regulation (EC) No 1333/2008 of the European Parliament and of the Council Text with EEA relevance". EUR-Lex. E 340 (i) MONOPOTASSIUM PHOSPHATE. Retrieved 19 January 2023.{{cite web}}: CS1 maint: location (link)
^Mathews, Christopher K., K. E. Van Holde, Ean R. Appling, and Spencer J. Anthony-Cahill. Biochemistry. Redwood City, CA: Benjamin/Cummings Pub., 1990. Print.
^ abOno, Yasuhiro; Hikita, Tomoyuki; Ikeda, Takuro (1987). "Phase Transitions in Mixed Crystal System K1−x(NH4)xH2PO4". Journal of the Physical Society of Japan. 56 (2): 577. Bibcode:1987JPSJ...56..577O. doi:10.1143/JPSJ.56.577.
^ abcd"Potassium Dihydrogen Phosphate". American Elements. Retrieved October 30, 2018.
^Klaus Schrödter; Gerhard Bettermann; Thomas Staffel; Friedrich Wahl; Thomas Klein; Thomas Hofmann (2012). "Phosphoric Acid and Phosphates". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a19_465.pub3.
^ abFukami, T. (1990). "Refinement of the Crystal Structure of KH2PO4 in the Ferroelectric Phase". Physica Status Solidi A. 117 (2): K93–K96. Bibcode:1990PSSAR.117...93F. doi:10.1002/pssa.2211170234.
^ abItoh, Kazuyuki; Matsubayashi, Tetsuo; Nakamura, Eiji; Motegi, Hiroshi (1975). "X-Ray Study of High-Temperature Phase Transitions in KH2PO4". Journal of the Physical Society of Japan. 39 (3): 843. Bibcode:1975JPSJ...39..843I. doi:10.1143/JPSJ.39.843.
^Gaasbeek, André; Meinders, A. Edo (October 2005). "Hypophosphatemia: an update on its etiology and treatment". The American Journal of Medicine. 118 (10): 1094–1101. doi:10.1016/j.amjmed.2005.02.014. ISSN 0002-9343. PMID 16194637.
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EPA: Potassium dihydrogen phosphate Fact Sheet
November 08, 2023
monopotassium, phosphate, also, potassium, dihydrogenphosphate, monobasic, potassium, phosphate, inorganic, compound, with, formula, kh2po4, together, with, dipotassium, phosphate, k2hpo4, often, used, fertilizer, food, additive, buffering, agent, salt, often,. Monopotassium phosphate MKP also potassium dihydrogenphosphate KDP or monobasic potassium phosphate is the inorganic compound with the formula KH2PO4 Together with dipotassium phosphate K2HPO4 H2O x it is often used as a fertilizer food additive and buffering agent The salt often cocrystallizes with the dipotassium salt as well as with phosphoric acid 7 Monopotassium phosphate Two unit cells of MKP viewed close to the b axisNamesIUPAC names Potassium dihydrogen phosphate 1 Other names Potassium phosphate monobasic Phosphoric acid monopotassium salt Potassium biphosphateIdentifiersCAS Number 7778 77 0 Y3D model JSmol Interactive imageChEMBL ChEMBL1200925 NChemSpider 22914 NECHA InfoCard 100 029 012EC Number 231 913 4E number E340 i antioxidants PubChem CID 516951RTECS number TC6615500UNII 4J9FJ0HL51 YCompTox Dashboard EPA DTXSID0035667InChI InChI 1S 3K H3O4P c 1 5 2 3 4 h H3 1 2 3 4 q3 1 p 3 YKey LWIHDJKSTIGBAC UHFFFAOYSA K YInChI 1 3K H3O4P c 1 5 2 3 4 h H3 1 2 3 4 q3 1 p 3Key LWIHDJKSTIGBAC DFZHHIFOAXSMILES K OP O O OPropertiesChemical formula KH2 PO4Molar mass 136 086 g molAppearance Colourless crystals or white granular or crystalline powder 2 Odor Odorless 2 Density 2 338 g cm3Melting point 252 6 C 486 7 F 525 8 K 4 Boiling point 400 C 752 F 673 K decomposesSolubility in water 22 6 g 100 mL 20 C 83 5 g 100 mL 90 C Solubility Slightly soluble in ethanolAcidity pKa 6 86 3 Basicity pKb 11 9Refractive index nD 1 4864StructureCrystal structure Tetragonal 5 Space group I4 2dLattice constant a 0 744 nm b 0 744 nm c 0 697 nmHazardsGHS labelling Pictograms 6 Signal word Warning 6 Hazard statements H315 H319 6 Precautionary statements P264 P280 P305 P351 P338 P321 P332 P313 P337 P313 6 NFPA 704 fire diamond 100Flash point Non flammableLethal dose or concentration LD LC LD50 median dose 3200 mg kg rat oral Safety data sheet SDS External MSDSRelated compoundsOther cations Monosodium phosphateMonoammonium phosphateRelated compounds Dipotassium phosphateTripotassium phosphateExcept where otherwise noted data are given for materials in their standard state at 25 C 77 F 100 kPa N verify what is Y N Infobox references Single crystals are paraelectric at room temperature At temperatures below 150 C 238 F they become ferroelectric Contents 1 Structure 2 Manufacturing 3 Applications 4 Gallery 5 References 6 External linksStructure editMonopotassium phosphate can exist in several polymorphs At room temperature it forms paraelectric crystals with tetragonal symmetry Upon cooling to 150 C 238 F it transforms to a ferroelectric phase of orthorhombic symmetry and the transition temperature shifts up to 50 C 58 F when hydrogen is replaced by deuterium 8 Heating to 190 C 374 F changes its structure to monoclinic 9 When heated further MKP decomposes by loss of water to potassium metaphosphate KPO3 at 400 C 752 F Symmetry Spacegroup Pearsonsymbol a nm b nm c nm Z Density g cm3 T C F K Orthorhombic 8 Fdd2 43 oF48 1 0467 1 0533 0 6926 8 2 37 lt 150 C 238 F 123 KTetragonal 5 I4 2d 122 tI24 0 744 0 744 0 697 4 2 34 150 to 190 C 238 to 374 F 123 to 463 KMonoclinic 9 P21 c 14 mP48 0 733 1 449 0 747 8 190 to 400 C 374 to 752 F 463 to 673 KManufacturing editMonopotassium phosphate is produced by the action of phosphoric acid on potassium carbonate Applications editFertilizer grade MKP powder contains the equivalent of 52 P2 O5 and 34 K2 O and is labeled NPK 0 52 34 MKP powder is often used as a nutrient source in the greenhouse trade and in hydroponics As a crystal MKP is noted for its non linear optical properties It is used in optical modulators and for non linear optics such as second harmonic generation SHG Also to be noted is KD P potassium dideuterium phosphate with slightly different properties Highly deuterated KDP is used in nonlinear frequency conversion of laser light instead of protonated regular KDP due to the fact that the replacement of protons with deuterons in the crystal shifts the third overtone of the strong OH molecular stretch to longer wavelengths moving it mostly out of the range of the fundamental line at approximately 1064 nm of neodymium based lasers Regular KDP has absorbances at this wavelength of approximately 4 7 6 3 per cm of thickness while highly deuterated KDP has absorbances of typically less than 0 8 per cm Monopotassium phosphate is also used as an ingredient in sports drinks such as Gatorade and Powerade In medicine monopotassium phosphate is used for phosphate substitution in hypophosphatemia 10 Gallery edit nbsp A large KDP crystal used in the form of slices at the National Ignition Facility nbsp Alternate angle coveredReferences edit Potassium dihydrogen phosphate a b Commission Regulation EU No 231 2012 of 9 March 2012 laying down specifications for food additives listed in Annexes II and III to Regulation EC No 1333 2008 of the European Parliament and of the Council Text with EEA relevance EUR Lex E 340 i MONOPOTASSIUM PHOSPHATE Retrieved 19 January 2023 a href Template Cite web html title Template Cite web cite web a CS1 maint location link Mathews Christopher K K E Van Holde Ean R Appling and Spencer J Anthony Cahill Biochemistry Redwood City CA Benjamin Cummings Pub 1990 Print King Harold S J Am Chem Soc 1927 49 6 1511 1512 https doi org 10 1021 ja01405a018 a b Ono Yasuhiro Hikita Tomoyuki Ikeda Takuro 1987 Phase Transitions in Mixed Crystal System K1 x NH4 xH2PO4 Journal of the Physical Society of Japan 56 2 577 Bibcode 1987JPSJ 56 577O doi 10 1143 JPSJ 56 577 a b c d Potassium Dihydrogen Phosphate American Elements Retrieved October 30 2018 Klaus Schrodter Gerhard Bettermann Thomas Staffel Friedrich Wahl Thomas Klein Thomas Hofmann 2012 Phosphoric Acid and Phosphates Ullmann s Encyclopedia of Industrial Chemistry Weinheim Wiley VCH doi 10 1002 14356007 a19 465 pub3 a b Fukami T 1990 Refinement of the Crystal Structure of KH2PO4 in the Ferroelectric Phase Physica Status Solidi A 117 2 K93 K96 Bibcode 1990PSSAR 117 93F doi 10 1002 pssa 2211170234 a b Itoh Kazuyuki Matsubayashi Tetsuo Nakamura Eiji Motegi Hiroshi 1975 X Ray Study of High Temperature Phase Transitions in KH2PO4 Journal of the Physical Society of Japan 39 3 843 Bibcode 1975JPSJ 39 843I doi 10 1143 JPSJ 39 843 Gaasbeek Andre Meinders A Edo October 2005 Hypophosphatemia an update on its etiology and treatment The American Journal of Medicine 118 10 1094 1101 doi 10 1016 j amjmed 2005 02 014 ISSN 0002 9343 PMID 16194637 External links edit nbsp Wikimedia Commons has media related to Monopotassium phosphate International Chemical Safety Card 1608 EPA Potassium dihydrogen phosphate Fact Sheet Potassium Phosphate a Hydroculture Salt Retrieved from https en wikipedia org w index php title Monopotassium phosphate amp oldid 1172598101, wikipedia, wiki, book, books, library,
