IUPAC-NIST Solubility Database
NIST Standard Reference Database 106

Glass Ball as Bullet Solubility System: Ammonium dihydrogenphosphate with Urea and Water
Components:
   (1) Ammonium dihydrogenphosphate; NH4H2PO4; [7722-76-1]  NIST Chemistry WebBook for detail
   (2) Urea; CH4N2O; [57-13-6]  NIST Chemistry WebBook for detail
   (3) Water; H2O; [7732-18-5]  NIST Chemistry WebBook for detail
Original Measurements:
   Sarbaev, A.N.; Polyakov, E.V.; Tyunina, M.F.; Polyakova, Z.A.; Ruchkova, A.Kh., Khim. Prom. (Moscow) 1972, 48, 437.

 Variables:

   Concentration = Composition and temperature in solutions with N/P2O5 ratio of 1:1.

 Prepared By:
   J. Eysseltová

 Experimental Remarks:
   The solubility polytherm for the NH4H2PO4-CO(NH2)2-H2O system in a solution having a N/P2O5 ratio = 1:1 is given in graphical form. The eutectic point is specified as 28.4 mass % of fertilizer 1:1 and 72.6 mass % H2O at –9.25 ºC. Compiler's Comment: The composition values are an obvious typographical error because the sum = 101%.

 Experimental Data:   (Notes on the Nomenclature)
  
Method/Apparatus/Procedure:
   The method has been described earlier.1

 Source and Purity of Materials:
   CO(NH2)2 was GOST 6691-67; NH4H2PO4 was GOST 3771-64. No other information is given.

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

 References:
   1Krichevskiy, I.R.; Khazanova, N.E.; Liushic, L.R. Zh. Fiz. Khim. 1957, 31, 2711.