IUPAC-NIST Solubility Database
NIST Standard Reference Database 106

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

   (1) Ammonia; NH3; [7664-41-7]  NIST Chemistry WebBook for detail
   (2) Tetraphosphoric acid; H6P4O13; [13813-62-2]  NIST Chemistry WebBook for detail
   (3) Water; H2O; [7732-18-5]  NIST Chemistry WebBook for detail

Original Measurements:
   Farr, T.D.; Willard, J.W.; Hatfield, J.D., J. Chem. Eng. Data 1972, 17, 313.


   Concentration = Composition at 273 K.

Prepared By:
   J. Eysseltová

Experimental Data:   (Notes on the Nomenclature)
(Please see footnotes following the table(s).)
Solubility values in the NH3-H6P4O13-H2O system at 273 K.
pHChemical1102 * Mass Fraction w1Chemical2100 * Mass Fraction w2Chemical3100 * Mass Fraction w3m3 [mol/kg]Chemical4100 * Mass Fraction w4m4 [mol/kg]Chemical5100 * Mass Fraction w5Solid Phase(s)(b)
2.25N8.94P2O546.00NH3 (a)10.8718.57H5P3O10 (a)54.764.71H2O (a)34.37A
2.81N9.24P2O546.06NH3 (a)11.2319.44H5P3O10 (a)54.834.78H2O (a)33.93A
3.56N9.65P2O546.67NH3 (a)11.7321.06H5P3O10 (a)55.565.03H2O (a)32.71A
3.66N9.81P2O546.67NH3 (a)11.9321.54H5P3O10 (a)55.565.06H2O (a)32.51A
4.07N10.56P2O548.32NH3 (a)12.8425.44H5P3O10 (a)57.525.74H2O (a)29.64A
4.02N10.77P2O548.64NH3 (a)13.0926.51H5P3O10 (a)57.905.91H2O (a)29.01A + B
4.25N10.72P2O547.76NH3 (a)13.0325.42H5P3O10 (a)56.865.59H2O (a)30.11B
4.74N10.83P2O545.83NH3 (a)13.1723.96H5P3O10 (a)54.565.00H2O (a)32.27B
4.83N10.95P2O545.52NH3 (a)13.3124.05H5P3O10 (a)54.194.93H2O (a)32.50B
4.85N11.03P2O545.58NH3 (a)13.4124.36H5P3O10 (a)54.264.97H2O (a)32.33C
5.47N10.70P2O543.15NH3 (a)13.0121.44H5P3O10 (a)51.374.27H2O (a)35.62C
5.76N10.37P2O538.84NH3 (a)12.6117.99H5P3O10 (a)46.243.32H2O (a)41.15C
5.76N10.38P2O538.64NH3 (a)12.6217.91H5P3O10 (a)46.003.29H2O (a)41.38C
6.28N10.31P2O536.07NH3 (a)12.5416.53H5P3O10 (a)42.942.85H2O (a)44.52C
----N11.00 (c)P2O545.50 (c)NH3 (a)13.3724.19H5P3O10 (a)54.174.94H2O (a)32.46B + C
   Table 1  a  These values were calculated by the compiler.
   Table 1  b  The solid phases are: A=(NH4)4H6P4O13; B=(NH4)5HP4O13·H2O; C=(NH4)6P4O13·2H2O.
   Table 1  c  The composition of this invariant point was estimated graphically from plots of pH vs N or P2O5.

   A stock solution was prepared by saturating conductivity water with (NH4)6P4O13·2H2O. Portions of this solution were adjusted with either anhydrous ammonia or the H-form of Amberlite IR-120 resin to a selected pH value and evaporated under vacuum at about 298 K to crystallization. The mixture was then equilibrated in a cold room for 15 days to 48 days. Phosphorus was determined gravimetrically as quinolinium molybdophosphate (1), and nitrogen was determined by distillation of ammonia with NaOH. The pH was measured, after warming to 298 K, with a conventional meter and a glass electrode.

Source and Purity of Materials:
   (NH4)6P4O13·2H2O of sufficient purity was prepared by a modification of 2 published procedures2,3. Conductivity water was used.

Estimated Errors:

   Temperature: The only information given is that the temperature was kept constant to within ± 0.5 K.

   1C. H. Perrin, J. Assoc. Offic. Agr. Chem. 41, 758 (1958).
   2G. J. Griffith, J. Inorg. Nucl. Chem. 26, 1381 (1964).
   3R. K. Osterheld and R. P. Langguth, J. Phys. Chem. 59, 76 (1955).