IUPAC-NIST Solubilities Database

IUPAC-NIST Solubility Database
NIST Standard Reference Database 106

Solubility System: Ammonia with Phosphoric acid and Water

Components:
   (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:
   Flatt, R.; Brunisholz, G.; Blumer, O., Helv. Chim. Acta 1955, 38, 753.

Variables:

   Concentration = Composition at 25 ºC.

Prepared By:
   J. Eysseltová

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

Composition of saturated solutions of the NH₄⁺-H⁺-PO₄^3–-H₂O system at 25 °C.
Chemical₁	Mass Fraction w₁	Chemical₂	Mass Fraction w₂	Chemical₃	10² * Mass Fraction w₃	m₃ [mol/kg]	Chemical₄	10² * Mass Fraction w₄	m₄ [mol/kg]	Chemical₅	10² * Mass Fraction w₅^(b)	Mole Fractio₅n	Solid Phase(s)^(c)
NH4+	12.8	H+	87.2	NH3 (b)	5.40	23.3	H3PO4 (b)	81.0	60.65	H2O	13.6	30.5	A + B
NH4+	12.8	H+	87.2	NH3 (b)	5.41	23.4	H3PO4 (b)	81.1	61.05	H2O	13.5	30.3	A + B
NH4+	12.8	H+	87.2	NH3 (b)	5.41	23.6	H3PO4 (b)	81.1	61.46	H2O	13.5	30.1	B
NH4+	12.8	H+	87.2	NH3 (b)	5.44	24.6	H3PO4 (b)	81.6	64.01	H2O	13.0	28.9	B
NH4+	12.7	H+	87.3	NH3 (b)	5.41	24.8	H3PO4 (b)	81.8	65.13	H2O	12.8	28.4	B
NH4+	12.7	H+	87.3	NH3 (b)	5.45	26.3	H3PO4 (b)	82.3	69.02	H2O	12.3	26.8	B + C
NH4+	11.4	H+	88.6	NH3 (b)	4.99	26.7	H3PO4 (b)	84.0	78.05	H2O	11.0	23.7	C
NH4+	10.3	H+	89.7	NH3 (b)	4.60	27.8	H3PO4 (b)	85.7	89.80	H2O	9.7	20.6	C
NH4+	10.1	H+	89.9	NH3 (b)	4.53	28.3	H3PO4 (b)	86.1	93.42	H2O	9.4	19.8	C
NH4+	9.2	H+	90.8	NH3 (b)	4.3	40.5	H3PO4 (b)	89.5	146.8	H2O	6.2	12.6	C
NH4+	8.9	H+	91.1	NH3 (b)	4.3	72.6	H3PO4 (b)	92.3	272.0	H2O	3.5	6.8	C
NH4+	9.2	H+	90.8	NH3 (b)	4.5	170	H3PO4 (b)	93.9	616.6	H2O	1.6	3.0	C
NH4+	9.2	H+	90.8	NH3 (b)	4.5	182	H3PO4 (b)	94.0	660.6	H2O	1.5	2.8	C
NH4+	9.3	H+	90.7	NH3 (b)	4.6	198	H3PO4 (b)	94.1	711.5	H2O	1.3	2.6	C
NH4+	9.1	H+	90.9	NH3 (b)	4.5	210	H3PO4 (b)	94.3	770.7	H2O	1.2	2.4	C
NH4+	4.0	H+	96.0	NH3 (b)	2.0	76.5	H3PO4 (b)	96.4	637.9	H2O	1.5	2.9	C
NH4+	4.0	H+	96.0	NH3 (b)	2.0	67.3	H3PO4 (b)	96.2	560.5	H2O	1.8	3.3	C
NH4+	1.2	H+	98.8	NH3 (b)	0.60	8.9	H3PO4 (b)	95.4	246.6	H2O	4.0	7.5	C
NH4+	0.0	H+	100.0	NH3 (b)	0.0	0.0	H3PO4 (b)	95.6	220.2	H2O	4.4	8.4	C

Notes:
   Table 1  ^a  The composition unit is mol/100 mol solute.
   Table 1  ^b  These values were calculated by the compiler.
   Table 1  ^c  The solid phases are A=NH₄H₂PO₄; B=(NH₄)₃H₉(PO₄)₄; C=NH₄H₅(PO₄)₂; D=H₃PO₄.

Method/Apparatus/Procedure:
   No information is given.

Source and Purity of Materials:
   No information is given.

Estimated Errors:

   Temperature: No information is given. The compiler estimates the reproducibility to be about 0.1 %.