查看“︁焦磷酸钾”︁的源代码

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| CustomizedImage=  [[File:4.svg|x35px|4 ·]] [[File:K+.svg|x35px|Struktur des Kaliumions]] [[File:Diphosphat-Ion.svg|160px|Struktur von Diphosphat]]
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| Section1 = {{Chembox Identifiers
|   CASNo = 7320-34-5
|   CASNo_Ref = {{cascite}}
|   PubChem = 23740
|   SMILES = [K+].[K+].[K+].[K+].[O-]P(=O)([O-])OP(=O)([O-])[O-] }}
| Section2 = {{Chembox Properties
|   Formula = K<sub>4</sub>P<sub>2</sub>O<sub>7</sub>
|   MolarMass = 330.34
|   Appearance = 白色固体<ref name="GESTIS">{{GESTIS|Name=Kaliumdiphosphat|ZVG=5380|CAS=7320-34-5|Abruf=2017-01-10}}</ref>
|   Density = 2.61 g·cm<sup>−3</sup><ref name="GESTIS" />
|   MeltingPt =1090  °C<ref name="Dale L. Perry">{{cite book| author=Dale L. Perry | title=Handbook of Inorganic Compounds | url=https://archive.org/details/handbookofinorga0000unse | publisher=CRC Press | ISBN=978084938671-8 | date=1995 | page=[https://archive.org/details/handbookofinorga0000unse/page/315 315] }}</ref> 
|   BoilingPt = 
|   Solubility = 1870 g/L（25 °C）<ref name="GESTIS" /> 
|SolubleOther=不溶于乙醇<ref name="RömppOnline">{{RömppOnline|ID=RD-11-00254|Name=Kaliumphosphate|Datum=2015-01-17}}</ref>
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'''焦磷酸钾'''（Potassium pyrophosphate）是[[钾]]的[[焦磷酸盐]]，分子式K<sub>4</sub>P<sub>2</sub>O<sub>7</sub>。

== 制备 ==
焦磷酸钾可以由[[磷酸氢二钾]]在 350 – 400 °C 下失水而成。<ref name="Arthur D. F. Toy">{{cite book| author=Arthur D. F. Toy | title=The Chemistry of Phosphorus: Pergamon Texts in Inorganic Chemistry | publisher=Elsevier | ISBN=978148314741-3 | date=2013 | page=513 }}</ref>
:<math>\mathrm{2 \ K_2HPO_4 \longrightarrow K_4P_2O_7 + H_2O}</math>

它也可以由[[碳酸钾]]和[[五氧化二磷]]反应而成。<ref name="Govindhan Dhanaraj, Kullaiah Byrappa, Vishwanath Prasad, Michael Dudley">{{cite book| author=Govindhan Dhanaraj, Kullaiah Byrappa, Vishwanath Prasad, Michael Dudley | title=Springer Handbook of Crystal Growth | publisher=Springer Science & Business Media | ISBN=978354074761-1 | date=2010 | page=740 }}</ref>
:<math>\mathrm{2 \ K_2CO_3 + P_2O_5 \longrightarrow K_4P_2O_7 + 2 \ CO_2}</math>

==性质==
焦磷酸钾是一种白色易潮解固体，极易溶于水。<ref name="GESTIS" />它的三水合物在 180 °C 下变成单水合物，在 330 °C 下变成无水物。<ref name="Dale L. Perry" />

==用途==
[[无氰电镀]]中用于替代[[氰化钠]]作为电镀的络合剂。用于配制清洗剂、洗涤剂。也用作粘土分散剂、颜料和染料的缓冲剂和分散剂，以及漂染中的除铁离子试剂。食品工业中，用作乳化剂、螯合剂、组织改进剂等。

==参考资料==
{{reflist}}
{{钾化合物}}
{{焦磷酸盐}}
[[Category:钾化合物]]
[[Category:焦磷酸盐]]
[[Category:缺少物质图片的化学品条目]]