IUPAC-NIST Solubility Database
NIST Standard Reference Database 106

Glass Ball as Bullet Solubility System: Ammonia with Phosphoric acid and Water

   (1) Ammonia; NH3; [7664-41-7]  NIST Chemistry WebBook for detail
   (2) Phosphoric acid; H3PO4; [7664-38-2]  NIST Chemistry WebBook for detail
   (3) Water; H2O; [7732-18-5]  NIST Chemistry WebBook for detail

Original Measurements:
   Mazunin, S.A.; Sosnina, O.E.; Volkov, A.A.; Danina, T.L., Termicheskiy Analiz i Fazovye Ravnovesiya, Perm, 79 (1985).; Sosnina, O.E.; Volkov, A.A., Uch. Zap. Perm. Gos. Univ., Ser. Khim. 289, 20 (1973).


   Concentration = Composition at 20 ºC and 60 ºC

Prepared By:
   L.V. Chernykh and J. Eysseltová

Experimental Data:   (Notes on the Nomenclature)
(Please see footnotes following the table(s).)
Solubility isotherms in the NH4H2PO4-(NH4)2HPO4-H2O system.
t/°CChemical1102 * Mass Fraction w1Chemical2102 * Mass Fraction w2Chemical3102 * Mass Fraction w3m3 [mol/kg]Chemical4102 * Mass Fraction w4m4 [mol/kg]Chemical5102 * Mass Fraction w5Solid Phase(s)(b)Refractive Index
20NH4H2PO40.0(NH4)2HPO440.8NH3 (a)10.510.4H3PO4 (a)30.35.2H2O (a)59.2A
20NH4H2PO46.0(NH4)2HPO439.0NH3 (a)11.011.7H3PO4 (a)34.16.3H2O (a)55.0A
20NH4H2PO49.0(NH4)2HPO438.0NH3 (a)11.112.3H3PO4 (a)35.96.9H2O (a)53.0A
20NH4H2PO412.0(NH4)2HPO437.0NH3 (a)11.313.0H3PO4 (a)37.77.5H2O (a)51.0A
20NH4H2PO416.0(NH4)2HPO436.0NH3 (a)11.614.3H3PO4 (a)40.38.6H2O (a)48.0A
20NH4H2PO426.0(NH4)2HPO432.0NH3 (a)12.116.9H3PO4 (a)45.911.2H2O (a)42.0A + B
20NH4H2PO424.0(NH4)2HPO431.5NH3 (a)11.715.4H3PO4 (a)43.810.1H2O (a)44.5"
20NH4H2PO425.0(NH4)2HPO423.0NH3 (a)9.610.9H3PO4 (a)38.47.5H2O (a)52.0"
20NH4H2PO426.0(NH4)2HPO414.0NH3 (a)7.57.3H3PO4 (a)32.55.5H2O (a)60.0"
20NH4H2PO427.0(NH4)2HPO47.0NH3 (a)5.85.2H3PO4 (a)28.24.4H2O (a)66.0"
20NH4H2PO427.3(NH4)2HPO40.0NH3 (a)4.03.3H3PO4 (a)23.33.3H2O (a)72.7"
60NH4H2PO40.0(NH4)2HPO448.8NH3 (a)12.614.4H3PO4 (a)36.27.2H2O (a)51.2A
60NH4H2PO46.5(NH4)2HPO445.7NH3 (a)12.815.7H3PO4 (a)39.48.4H2O (a)47.8A
60NH4H2PO413.1(NH4)2HPO442.7NH3 (a)13.017.2H3PO4 (a)42.89.9H2O (a)44.2A
60NH4H2PO420.4(NH4)2HPO440.5NH3 (a)13.520.2H3PO4 (a)47.412.4H2O (a)39.1A
60NH4H2PO426.7(NH4)2HPO438.3NH3 (a)13.823.2H3PO4 (a)51.214.9H2O (a)35.0A
60NH4H2PO435.1(NH4)2HPO435.0NH3 (a)14.227.9H3PO4 (a)55.919.1H2O (a)29.9A + B
60NH4H2PO435.7(NH4)2HPO431.8NH3 (a)13.524.4H3PO4 (a)54.017.0H2O (a)32.5B
60NH4H2PO436.4(NH4)2HPO425.2NH3 (a)11.918.2H3PO4 (a)49.713.2H2O (a)38.4B
60NH4H2PO439.3(NH4)2HPO417.6NH3 (a)10.414.1H3PO4 (a)46.511.0H2O (a)43.1B
60NH4H2PO440.8(NH4)2HPO411.2NH3 (a)8.910.9H3PO4 (a)43.19.2H2O (a)48.0B
   Table 1  a  These values were calculated by the compiler.
   Table 1  b  The solid phases are: A=(NH4)2HPO4; B=NH4H2PO4.

   The refractometric variation of the isothermal method was used. The compilers assume that it was the method described elsewhere.1 NH4H2PO4 and (NH4)2HPO4 were determined by potentiometric titration. The composition of the solid phase was determined by the Schreinemaker's method.

Source and Purity of Materials:
   No information is given, but the compilers assume that the materials were the same as those used in Ref. 2.

Estimated Errors:
   Solubility: The precision of the analysis of NH4H2PO4 and (NH4)2HPO4 was 0.2% and 0.6%, respectively.

   1Zhuravlev, E.F.; Sheveleva, A.D. Zh. Neorg. Khim. 1960, 5, 2630.
   2Sosnina, O.E.; Volkov, A.A. Uch. Zap. Perm. Gos. Univ., Ser. Khim. 1973, 289, 20.