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Zinc pyrophosphate

Zinc pyrophosphate[1]
Zinc pyrophosphate
Names
Other names
Dizinc diphosphate
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.028.367 Edit this at Wikidata
UNII
  • InChI=1S/H4O7P2.2Zn/c1-8(2,3)7-9(4,5)6;;/h(H2,1,2,3)(H2,4,5,6);;/q;2*+2/p-4 checkY
    Key: OMSYGYSPFZQFFP-UHFFFAOYSA-J checkY
  • InChI=1/H4O7P2.2Zn/c1-8(2,3)7-9(4,5)6;;/h(H2,1,2,3)(H2,4,5,6);;/q;2*+2/p-4
    Key: OMSYGYSPFZQFFP-XBHQNQODAA
  • [Zn+2].[Zn+2].[O-]P([O-])(=O)OP([O-])([O-])=O
Properties
Zn2P2O7
Molar mass 304.72 g/mol
Appearance White crystalline powder
Density 3.75 g/cm3
Insoluble
Solubility Soluble in dilute acids
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Zinc pyrophosphate (Zn2P2O7) is an ionic inorganic chemical compound composed of Zn2+ cations and pyrophosphate anions.

Preparation

Zinc pyrophosphate can be obtained from the thermal decomposition of zinc ammonium phosphate.[2]

2 ZnNH4PO4 → Zn2P2O7 + 2 NH3 + H2O

It can also be obtained from the reaction between sodium carbonate, zinc oxide, and ammonium dihydrogen phosphate.[3]

Na2CO3 + 2 ZnO + 2 (NH4)H2PO4 → Zn2P2O7 + 2 NaOH + 2 NH3 + 2 H2O + CO2

It is also produced when a strongly acidic solution of zinc sulfate is heated with sodium pyrophosphate.[4]

2 ZnSO4 + Na4P2O7 → Zn2P2O7 + 2 Na2SO4

Another method is precipitating zinc as a phosphate, then heating over 1123 K.[citation needed]

Properties

Zinc pyrophosphate is a white crystalline solid that is insoluble in water.[5] On heating in water, it decomposes to form Zn3(PO4)2 and ZnHPO4. It crystallizes in the monoclinic system. The α-form crystallizes at low temperatures and the β-form crystallizes at high temperatures.[2][3]

Uses

Zinc pyrophosphate is used as a pigment.[5] It is useful in gravimetric analysis of zinc.[6]

References

  1. ^ Lide, David R. (1998), Handbook of Chemistry and Physics (87 ed.), Boca Raton, Florida: CRC Press, pp. 4–96, ISBN 0-8493-0594-2
  2. ^ a b Calvo, Crispin (1965-05-01). "THE CRYSTAL STRUCTURE AND PHASE TRANSITIONS OF β-Zn 2 P 2 O 7". Canadian Journal of Chemistry. 43 (5): 1147–1153. doi:10.1139/v65-152. ISSN 0008-4042.
  3. ^ a b Jarboui, A.; Ben Rhaeim, A.; Hlel, F.; Guidara, K; Gargouri, M. (2010). "NMR study and electrical properties investigation of Zn2P2O7". Ionics. 16 (1): 67–73. doi:10.1007/s11581-009-0333-5. ISSN 0947-7047. S2CID 94790682.
  4. ^ Ochs, Rudolf (2013). Praktikum der Qualitativen Analyse Für Chemiker · Pharmazeuten und Mediziner. Berlin, Heidelberg: Springer-Verlag. p. 117. ISBN 978-3-662-28315-8. OCLC 860357745.
  5. ^ a b Perry, Dale L. (2016). Handbook of Inorganic Compounds (2nd ed.). Boca Raton, FL: CRC Press. p. 469. ISBN 978-1-4398-1462-8. OCLC 759865801.
  6. ^ Holleman, Arnold F.; Wiberg, Egon; Wiberg, Nils (1995). Lehrbuch der anorganischen Chemie (102nd ed.). Berlin: de Gruyter. p. 1493. ISBN 978-3-11-012641-9. OCLC 237142268.
Quelle: http://en.wikipedia.org/wiki/Zinc_pyrophosphate