IUPAC-NIST Solubility Database
NIST Standard Reference Database 106

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 Solubility System: Ammonia with Phosphoric acid, Hydrogen chloride and Water

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Components:
   (1) Ammonia; NH3; [7664-41-7]  NIST Chemistry WebBook for detail
   (2) Hydrogen chloride; HCl; [7647-01-0]  NIST Chemistry WebBook for detail
   (3) Phosphoric acid; H3PO4; [7664-38-2]  NIST Chemistry WebBook for detail
   (4) Water; H2O; [7732-18-5]  NIST Chemistry WebBook for detail

Original Measurements:
   Volkov, A.A.; Sosnina, O.E., Izv. Vuzov. Khim. Khim. Tekhnol. 1974, 17, 1725.

Variables:

   Concentration = Composition at 20 ºC

Prepared By:
   J. Eysseltová

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

Solubility in the NH₄⁺, H⁺ || PO₄^3–, Cl^– -H₂O system at 20 °C.

Solution number	Chemical1	102 * Mass Fraction w1	Chemical2	102 * Mass Fraction w2	Chemical3	102 * Mass Fraction w3	Chemical4	102 * Mass Fraction w4	Solid Phase(s)(a)
1	NH4Cl	----	H3PO4	22.8	(NH4)3PO4	77.2	H2O	60.5	A + B
2	NH4Cl	----	H3PO4	38.6	(NH4)3PO4	61.4	H2O	41.6	B + C
3	NH4Cl	----	H3PO4	81.4	(NH4)3PO4	18.6	H2O	13.3	C + D
4	NH4Cl	----	H3PO4	85.3	(NH4)3PO4	14.7	H2O	11.5	D + E
5b	NH4Cl	5.0	H3PO4	87.7	(NH4)3PO4	----	H2O	11.5	F
6	NH4Cl	10.5	H3PO4	89.5	(NH4)3PO4	----	H2O	11.5	"
7	NH4Cl	3.8	H3PO4	79.4	(NH4)3PO4	16.8	H2O	----	C + D + F
8	NH4Cl	25.3	H3PO4	62.5	(NH4)3PO4	12.2	H2O	46.0	C + F
9	NH4Cl	45.5	H3PO4	45.5	(NH4)3PO4	9.0	H2O	59.5	"
10	NH4Cl	46.4	H3PO4	45.1	(NH4)3PO4	8.5	H2O	59.0	"
11	NH4Cl	65.1	H3PO4	27.9	(NH4)3PO4	7.0	H2O	67.5	"
12	NH4Cl	84.8	H3PO4	8.6	(NH4)3PO4	6.6	H2O	70.5	"
13	NH4Cl	48.3	H3PO4	20.7	(NH4)3PO4	31.0	H2O	58.5	"
14	NH4Cl	15.1	H3PO4	31.5	(NH4)3PO4	53.4	H2O	46.0	B + C
15	NH4Cl	27.1	H3PO4	27.2	(NH4)3PO4	45.7	H2O	50.0	B + C + F
16	NH4Cl	44.1	H3PO4	18.9	(NH4)3PO4	37.0	H2O	61.0	B + F
17	NH4Cl	64.1	H3PO4	8.8	(NH4)3PO4	27.1	H2O	65.0	"
18	NH4Cl	77.8	H3PO4	----	(NH4)3PO4	22.2	H2O	68.5	A + F
19	NH4Cl	65.6	H3PO4	3.5	(NH4)3PO4	30.9	H2O	65.2	A + B + F
20	NH4Cl	32.9	H3PO4	14.1	(NH4)3PO4	53.0	H2O	66.0	A + B
21	NH4Cl	18.8	H3PO4	18.7	(NH4)3PO4	62.5	H2O	63.0	"

Solution number	Chemical1	102 * Mass Fraction w1	m1 [mol/kg]	Chemical2	102 * Mass Fraction w2	m2 [mol/kg]	Chemical3	102 * Mass Fraction w3	m3 [mol/kg]	Chemical4	102 * Mass Fraction w4
1	NH3	10.4	10.1	H3PO4	29.0	4.90	HCl	0	0	H2O	60.5
2	NH3	12.3	17.3	H3PO4	46.1	11.3	HCl	0	0	H2O	41.6
3	NH3	5.53	24.4	H3PO4	81.2	62.3	HCl	0	0	H2O	13.3
4	NH3	4.46	22.8	H3PO4	84.0	74.6	HCl	0	0	H2O	11.5
5	NH3	1.41	7.76	H3PO4	77.6	74.3	HCl	10.3	26.5	H2O	10.7
6	NH3	2.96	15.1	H3PO4	79.2	70.3	HCl	6.33	15.1	H2O	11.5
7	NH3	6.97	xxx (a)	H3PO4	90.4	xxx (a)	HCl	2.59	XXX (a)	H2O	0
8	NH3	6.61	8.43	H3PO4	38.1	8.44	HCl	9.31	5.55	H2O	46.0
9	NH3	7.11	7.02	H3PO4	20.8	3.57	HCl	12.6	5.79	H2O	59
10	NH3	7.25	7.22	H3PO4	20.8	3.59	HCl	13.0	6.03	H2O	59.0
11	NH3	7.51	6.54	H3PO4	10.6	1.60	HCl	14.4	5.86	H2O	67.5
12	NH3	8.63	7.19	H3PO4	3.82	0.552	HCl	17.1	6.63	H2O	70.5
13	NH3	10.8	10.8	H3PO4	17.0	2.97	HCl	13.7	6.40	H2O	58.5
14	NH3	12.5	15.9	H3PO4	36.0	7.98	HCl	5.56	3.31	H2O	46.0
15	NH3	12.1	14.3	H3PO4	28.6	5.84	HCl	9.24	5.07	H2O	50.0
16	NH3	10.4	10.0	H3PO4	16.9	2.82	HCl	11.7	5.27	H2O	61.0
17	NH3	10.4	9.39	H3PO4	9.31	1.46	HCl	15.3	6.45	H2O	65.0
18	NH3	10.2	8.74	H3PO4	4.60	0.685	HCl	16.7	6.69	H2O	68.5
19	NH3	11.0	9.86	H3PO4	8.29	1.30	HCl	15.6	6.54	H2O	65.2
20	NH3	9.73	8.66	H3PO4	16.6	2.57	HCl	7.63	3.17	H2O	66.0
21	NH3	10.1	9.45	H3PO4	22.1	3.58	HCl	4.74	2.06	H2O	63.0

Notes:
   Table 1  ^a  The solid phases are A=(NH₄)₃PO₄·3H₂O; B=(NH₄)₂HPO₄; C=NH₄H₂PO₄; D=3NH₄H₂PO₄·H₃PO₄; E=NH₄H₂PO₄·H₃PO₄; F=NH₄Cl.
   Table 1  ^b  In this solution, 0.073 w (presumably of solute-compiler) HCl was present.
   Table 2  ^a  The molalities could not be calculated because the respective liquid phase was anhydrous.

Method/Apparatus/Procedure:
   The isothermal method of sections (1, 2) was used with the aid of refractive index measurements. Seven sections were studied.

Source and Purity of Materials:
   Chemically pure H₃PO₄, recrystallized ammonium phosphates, and reagent grade NH₄Cl were used. (NH₄)₃PO₄ was synthesized according to the method of Schottlander (no details given). Its solubility was 12.8 %.

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

References:
   ¹Merclin, R.V. Izv. biolog. n.-i. in-ta pri Permsk. un-te. 1937, 11, 1.
   ²Zhuravlev, E.F.; Sheveleva, A.D. Zh. Neorg. Khim. 1960, 5, 2360.

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Last updated: February 18, 2015 (Created: August 17, 2007)