IUPAC-NIST Solubilities Database

IUPAC-NIST Solubility Database
NIST Standard Reference Database 106

Solubility System: Ammonium dihydrogenphosphate with Diammonium hydrogenphosphate, Urea, Ammonium nitrate, Potassium chloride, and Water

Components:
   (1) Ammonium dihydrogenphosphate; NH4H2PO4; [7722-76-1]  NIST Chemistry WebBook for detail
   (2) Ammonium nitrate; NH4NO3; [6484-52-2]  NIST Chemistry WebBook for detail
   (3) Diammonium hydrogenphosphate; (NH4)2HPO4; [7783-28-0]  NIST Chemistry WebBook for detail
   (4) Potassium chloride; KCl; [7747-40-7]  NIST Chemistry WebBook for detail
   (5) Urea; CH4N2O; [57-13-6]  NIST Chemistry WebBook for detail
   (6) Water; H2O; [7732-18-5]  NIST Chemistry WebBook for detail

Original Measurements:
   Slack, A.V.; Hatfield, J.D.; Shaffer, H.B.; Driskell, J.C., J. Agr. Food Chem. 1959, 7, 404.

Variables:

   Concentration = Composition at 271.5 K with the mol ratio CO(NH₂)₂/NH₄NO₃ = 1.065.

Prepared By:
   J. Eysseltová

Experimental Remarks:

   Remarks: Solubility (expressed as N + P₂O₅ + K₂O) in the NH₄H₂PO₄-(NH₄)₂HPO₄-CO(NH₂)₂-NH₄NO₃-KCl-H₂O system at 271.5 K with the mol ratio CO(NH₂)₂/NH₄NO₃ = 1.065.

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

Mol ratio NH₃H₃PO₄
Chemical₁	Mole Fraction₁	Comment(s)
Nutrient ratio (1-3-0) (a)	1.5	Amount N + P<2>O<5> + K<2>O of in the system = 33.7 (b)
Nutrient ratio (1-3-0) (a)	1.6	32.9 (c)
Nutrient ratio (1-3-0) (a)	1.7	33.9 (c)
Nutrient ratio (1-2-0) (a)	1.5	31.3 (b)
Nutrient ratio (1-2-0) (a)	1.6	30.5 (c)
Nutrient ratio (1-2-0) (a)	1.7	30.5 (c)
Nutrient ratio (1-1-0) (a)	1.5	28.0 (b)
Nutrient ratio (1-1-0) (a)	1.6	27.5 (c)
Nutrient ratio (1-1-0) (a)	1.7	36.9 (c)
Nutrient ratio (2-1-0) (a)	1.5	26.9 (b)
Nutrient ratio (2-1-0) (a)	1.6	25.7 (c)
Nutrient ratio (2-1-0) (a)	1.7	23.7 (c)
Nutrient ratio (1-3-1) (a)	1.5	32.1 (b)
Nutrient ratio (1-3-1) (a)	1.6	34.1 (c)
Nutrient ratio (1-3-1) (a)	1.7	31.9 (c)
Nutrient ratio (1-2-1) (a) (d)	1.5	29.1
Nutrient ratio (1-2-1) (a) (d)	1.6	29.5
Nutrient ratio (1-2-1) (a) (d)	1.7	30.1
Nutrient ratio (1-1-1) (a) (d)	1.5	20.5
Nutrient ratio (1-1-1) (a) (d)	1.6	20.7
Nutrient ratio (1-1-1) (a) (d)	1.7	21.3
Nutrient ratio (2-1-2) (a) (d)	1.5	16.7
Nutrient ratio (2-1-2) (a) (d)	1.6	16.5
Nutrient ratio (2-1-2) (a) (d)	1.7	16.5
Nutrient ratio (1-3-3) (a) (e)	1.5	24.5
Nutrient ratio (1-3-3) (a) (e)	1.6	24.6
Nutrient ratio (1-3-3) (a) (e)	1.7	24.3
Nutrient ratio (1-2-3) (a) (e)	1.5	22.7
Nutrient ratio (1-2-3) (a) (e)	1.6	22.3
Nutrient ratio (1-2-3) (a) (e)	1.7	22.3
Nutrient ratio (1-1-3) (a) (e)	1.5	19.9
Nutrient ratio (1-1-3) (a) (e)	1.6	19.7
Nutrient ratio (1-1-3) (a) (e)	1.7	19.9
Nutrient ratio (2-1-6) (a) (e)	1.5	18.1
Nutrient ratio (2-1-6) (a) (e)	1.6	18.3
Nutrient ratio (2-1-6) (a) (e)	1.7	18.3

Notes:
   Table 1  ^a  The nutrient ratio is the weight ratio N:P₂O₅·K₂O.
   Table 1  ^b  NH₄H₂PO₄ is the solid phase in equilibrium with the above solution.
   Table 1  ^c  (NH₄)₂HPO₄ is the solid phase in equilibrium with the above solution.
   Table 1  ^d  KNO₃ is the solid phase in equilibrium with the above solution.
   Table 1  ^e  KCl is the solid phase in equilibrium with the above solution.

Method/Apparatus/Procedure:
   A series of solutions of each ratio, differing by small increments of water content, were cooled to –1.5 °C, and each solution (about 50 ml) was seeded with about 50 mg of crystals. The mixtures were agitated mildly for about 3 days. The disappearance or growth of crystals in the samples in this period permitted determination of the solubility.

Source and Purity of Materials:
   All the salts used were reagent grade. The water was deionized.

Estimated Errors:

   Temperature: The temperature was kept constant to within –1.5 ±0.7 °C. The solubility was determined within 0.1 to 0.2 % of the plant nutrient.