IUPAC-NIST Solubility Database
NIST Standard Reference Database 106

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 Solubility System: Ammonium dihydrogenphosphate with Diammonium hydrogenphosphate and Water

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Components:
   (1) Ammonium dihydrogenphosphate; NH4H2PO4; [7722-76-1]  NIST Chemistry WebBook for detail
   (2) Diammonium hydrogenphosphate; (NH4)2HPO4; [7783-28-0]  NIST Chemistry WebBook for detail
   (3) Water; H2O; [7732-18-5]  NIST Chemistry WebBook for detail

Original Measurements:
   Chomyakov, K.; Yaworovskaya, A.; Shirokikh, P., Z. Phys. Chem. A 1933, 167, 36.

Variables:

   Concentration = Composition at 23 ºC.

Prepared By:
   J. Eysseltová

Experimental Data:   (Notes on the Nomenclature)
(Please see footnotes following the table(s).)   

Solubility of ammonium phosphates in water at 23 °C.

Chemical1	102 * Mass Fraction w1	Mole Fraction1	m1 [mol/kg](a)	Chemical2	102 * Mass Fraction w2(a)
NH4H2PO4	28.3		3.43	H2O	71.7
(NH4)2HPO4	41.1		5.28	H2O	58.9

Notes:
   Table 1  ^a  These values were calculated by the compiler.

Method/Apparatus/Procedure:
   The solubility was found graphically from the plot of density vs composition.

Source and Purity of Materials:
   All materials were from de Haen or Kahlbaum and were purified twice, pulverized, and dried in vacuum before being used.

Estimated Errors:
   Solubility: No information is given.
   Temperature: No information is given.

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Last updated: February 18, 2015 (Created: August 17, 2007)