IUPAC-NIST Solubility Database
NIST Standard Reference Database 106

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 Solubility System: Ammonia with Phosphoric acid, Sulfuric acid and Water

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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) Sulfuric acid; H2SO4; [7664-93-9]  NIST Chemistry WebBook for detail
   (4) Water; H2O; [7732-18-5]  NIST Chemistry WebBook for detail

Original Measurements:
   Mishchenko, Yu.S.; Chepelevetskiy, M.L., Tr. NIUIFa 1965, 208, 30.

Variables:

   Concentration = Composition at 50 ºC

Prepared By:
   L.V. Chernykh and J. Eysseltová

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

Composition of saturated solutions in the (NH₄)₂HPO₄-(NH₄)₂SO₄-H₃PO₄-H₂O system at 50 °C.

Solution number	Chemical1	Composition1	102 * Mass Fraction w1	Chemical2	102 * Mass Fraction w2	Chemical3	102 * Mass Fraction w3	Chemical4	102 * Mass Fraction w4	Chemical5	102 * Mass Fraction w5	Chemical6	102 * Mass Fraction w6	Solid Phase(s)A + B + C
1	NH3		10.74	P2O5	20.7	SO3	20.3	(NH4)2HPO4	7.2	(NH4)2SO4	33.4	H3PO4	27.6	A + B + C
2	NH3		10.71	P2O5	20.0	SO3	21.0	(NH4)2HPO4	7.0	(NH4)2SO4	34.6	H3PO4	22.4	A + B
3	NH3		10.70	P2O5	16.5	SO3	21.7	(NH4)2HPO4	5.9	(NH4)2SO4	35.8	H3PO4	18.5	"
4	NH3		10.8	P2O5	14.2	SO3	22.4	(NH4)2HPO4	5.1	(NH4)2SO4	36.9	H3PO4	15.9	"
5	NH3		11.65	P2O5	12.8	SO3	22.6	(NH4)2HPO4	8.4	(NH4)2SO4	37.4	H3PO4	11.7	"
6	NH3		11.35	P2O5	11.01	SO3	22.8	(NH4)2HPO4	6.5	(NH4)2SO4	37.7	H3PO4	10.4	"
7	NH3		11.6	P2O5	10.6	SO3	23.0	(NH4)2HPO4	7.4	(NH4)2SO4	38.0	H3PO4	8.7	"
8	NH3		12.16	P2O5	9.27	SO3	24.0	(NH4)2HPO4	7.7	(NH4)2SO4	39.6	H3PO4	7.0	"
9	NH3		11.82	P2O5	9.05	SO3	22.9	(NH4)2HPO4	8.1	(NH4)2SO4	37.8	H3PO4	6.0	"
10	NH3		12.35	P2O5	9.53	SO3	21.4	(NH4)2HPO4	9.9	(NH4)2SO4	35.4	H3PO4	5.7	"
11	NH3		30.05	P2O5	14.5	SO3	20.25	(NH4)2HPO4	17.3	(NH4)2SO4	33.4	H3PO4	7.2	"
12	NH3		12.75	P2O5	23.05	SO3	13.95	(NH4)2HPO4	23.0	(NH4)2SO4	25.5	H3PO4	12.1	"
13	NH3		13.6	P2O5	29.3	SO3	10.8	(NH4)2HPO4	34.9	(NH4)2SO4	17.8	H3PO4	14.5	"
14	NH3		14.39	P2O5	31.75	SO3	9.16	(NH4)2HPO4	40.7	(NH4)2SO4	15.1	H3PO4	13.6	A + B + D
15	NH3		13.85	P2O5	11.35	SO3	20.89	(NH4)2HPO4	21.1	(NH4)2SO4	34.4	H3PO4	0.0	A + D
16	NH3		13.46	P2O5	12.34	SO3	20.45	(NH4)2HPO4	19.3	(NH4)2SO4	33.8	H3PO4	2.6	A + B + D (b)
17	NH3		13.65	P2O5	16.20	SO3	17.20	(NH4)2HPO4	24.7	(NH4)2SO4	28.3	H3PO4	8.9	"
18	NH3		14.02	P2O5	26.1	SO3	13.25	(NH4)2HPO4	33.7	(NH4)2SO4	21.9	H3PO4	11.0	"
19	NH3		14.00	P2O5	28.7	SO3	11.74	(NH4)2HPO4	34.9	(NH4)2SO4	19.4	H3PO4	13.6	"
20	NH3		14.08	P2O5	29.7	SO3	10.15	(NH4)2HPO4	37.9	(NH4)2SO4	16.7	H3PO4	12.8	"
21	NH3		14.39	P2O5	31.75	SO3	9.16	(NH4)2HPO4	40.7	(NH4)2SO4	15.1	H3PO4	13.6	"
22	NH3		13.5	P2O5	38.5	SO3	----	(NH4)2HPO4	54.0	(NH4)2SO4	0.0	H3PO4	13.1	B + D
23	NH3		14.01	P2O5	37.7	SO3	2.27	(NH4)2HPO4	50.6	(NH4)2SO4	3.8	H3PO4	14.5	"
24	NH3		14.34	P2O5	34.0	SO3	6.49	(NH4)2HPO4	45.0	(NH4)2SO4	10.7	H3PO4	13.5	"
25	NH3		14.42	P2O5	32.2	SO3	7.34	(NH4)2HPO4	44.0	(NH4)2SO4	12.1	H3PO4	11.8	"
26	NH3		14.19	P2O5	31.6	SO3	8.79	(NH4)2HPO4	40.7	(NH4)2SO4	14.5	H3PO4	13.5	"
27	NH3		14.39	P2O5	31.75	SO3	9.16	(NH4)2HPO4	40.7	(NH4)2SO4	15.1	H3PO4	13.6	A + B + D
28	NH3		10.74	P2O5	20.7	SO3	20.3	(NH4)2HPO4	7.2	(NH4)2SO4	33.4	H3PO4	27.6	A + B + C
29	NH3		9.93	P2O5	24.6	SO3	18.8	(NH4)2HPO4	7.5	(NH4)2SO4	31.0	H3PO4	28.5	B + C
30	NH3		9.12	P2O5	25.9	SO3	16.5	(NH4)2HPO4	8.2	(NH4)2SO4	27.2	H3PO4	29.7	"
31	NH3		7.32	P2O5	31.0	SO3	10.7	(NH4)2HPO4	10.8	(NH4)2SO4	17.6	H3PO4	34.8	"
32	NH3		11.73	P2O5	----	SO3	41.7	(NH4)2HPO4	0.0	(NH4)2SO4	45.6	H2SO4	17.3	A + E
33	NH3		11.6	P2O5	2.36	SO3	40.5	(NH4)2HPO4	4.4	(NH4)2SO4	41.0	H2SO4	19.2	"
34	NH3		11.45	P2O5	3.44	SO3	40.3	(NH4)2HPO4	6.4	(NH4)2SO4	38.0	H2SO4	21.2	"
35	NH3		11.3	P2O5	6.15	SO3	38.2	(NH4)2HPO4	11.4	(NH4)2SO4	32.6	H2SO4	22.5	"
36	NH3		11.3	P2O5	10.0	SO3	35.9	(NH4)2HPO4	18.6	(NH4)2SO4	26.0	H2SO4	24.6	"
37	NH3		11.3	P2O5	10.6	SO3	35.6	(NH4)2HPO4	19.6	(NH4)2SO4	24.2	H2SO4	25.4	A + C + E
38	NH3		12.23	P2O5	----	SO3	57.6	(NH4)2HPO4	0.0	(NH4)2SO4	49.5	H2SO4	33.8	E + F
39	NH3		12.57	P2O5	1.83	SO3	57.6	(NH4)2HPO4	3.3	(NH4)2SO4	45.6	H2SO4	35.4	"
40	NH3		12.1	P2O5	4.43	SO3	55.95	(NH4)2HPO4	8.3	(NH4)2SO4	38.8	H2SO4	39.3	"
41	NH3		11.8	P2O5	6.24	SO3	54.45	(NH4)2HPO4	11.6	(NH4)2SO4	34.2	H2SO4	41.2	C + E + F
42	NH3		11.3	P2O5	10.6	SO3	35.6	(NH4)2HPO4	19.6	(NH4)2SO4	24.2	H2SO4	25.4	A + C + E
43	NH3		10.59	P2O5	10.11	SO3	36.2	(NH4)2HPO4	18.8	(NH4)2SO4	22.3	H2SO4	27.8	C + E
44	NH3		10.1	P2O5	7.65	SO3	41.8	(NH4)2HPO4	14.2	(NH4)2SO4	24.9	H2SO4	33.5	"
45	NH3		11.8	P2O5	6.24	SO3	54.15	(NH4)2HPO4	11.6	(NH4)2SO4	34.2	H2SO4	41.2	C + E + F

Composition of  saturated solutions in the (NH₄)₂HPO₄-(NH₄)₂SO₄-H₃PO₄-H₂SO₄-H₂O system at 50 °C.

Solution number	Chemical1	102 * Mass Fraction w1	Chemical2	102 * Mass Fraction w2	Chemical3	102 * Mass Fraction w3	Solid Phase(s)(a)
46	NH3	10.74	P2O5	20.7	SO3	20.3	A + B + C
47	NH3	11.01	P2O5	17.81	SO3	25.43	A + B
48	NH3	10.9	P2O5	13.1	SO3	32.1	"
49	NH3	11.0	P2O5	11.9	SO3	33.7	"
50	NH3	11.3	P2O5	10.6	SO3	35.6	A + B + G

Part 2. The compilers have calculated the following values from the authors' data for the NH₃, P₂O₅ and SO₃ contents.

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	10.74	17.61	H3PO4	28.6	8.14	H2SO4	24.9	7.08	H2O	35.8
2	NH3	10.71	17.49	H3PO4	27.6	7.84	H2SO4	25.7	7.30	H2O	36.0
3	NH3	10.70	15.73	H3PO4	22.8	5.82	H2SO4	26.6	6.79	H2O	39.9
4	NH3	10.8	15.0	H3PO4	19.6	4.75	H2SO4	27.4	6.64	H2O	42.2
5	NH3	11.65	15.91	H3PO4	17.7	4.19	H2SO4	27.7	6.57	H2O	43.0
6	NH3	11.35	14.64	H3PO4	15.2	3.41	H2SO4	27.9	6.26	H2O	45.5
7	NH3	11.6	14.9	H3PO4	14.6	3.28	H2SO4	28.2	6.30	H2O	45.6
8	NH3	12.16	15.64	H3PO4	12.8	2.86	H2SO4	29.4	6.57	H2O	45.6
9	NH3	11.82	14.57	H3PO4	12.5	2.68	H2SO4	28.1	6.00	H2O	47.6
10	NH3	12.35	15.02	H3PO4	13.2	2.78	H2SO4	26.2	5.54	H2O	48.3
11	NH3	30.05	70.23	H3PO4	20.0	8.13	H2SO4	24.8	10.1	H2O	25.1
12	NH3	12.75	19.53	H3PO4	31.8	8.47	H2SO4	17.1	4.54	H2O	38.3
13	NH3	13.6	24.4	H3PO4	40.5	12.6	H2SO4	13.2	4.12	H2O	32.7
14	NH3	14.39	27.66	H3PO4	43.8	14.6	H2SO4	11.2	3.74	H2O	30.6
15	NH3	13.85	18.12	H3PO4	15.7	3.56	H2SO4	25.6	5.81	H2O	44.9
16	NH3	13.46	17.78	H3PO4	17.0	3.91	H2SO4	25.0	5.75	H2O	44.5
17	NH3	13.65	18.68	H3PO4	22.4	5.32	H2SO4	21.1	5.01	H2O	42.9
18	NH3	14.02	24.42	H3PO4	26.0	10.9	H2SO4	16.2	4.91	H2O	33.7
19	NH3	14.00	25.70	H3PO4	39.6	12.6	H2SO4	14.4	4.58	H2O	32.0
20	NH3	14.08	25.46	H3PO4	41.0	12.9	H2SO4	12.4	3.90	H2O	32.5
21	NH3	14.39	27.66	H3PO4	43.8	14.6	H2SO4	11.2	3.74	H2O	30.6
22	NH3	13.5	23.8	H3PO4	53.2	16.3	H2SO4	0.0	0.0	H2O	33.3
23	NH3	14.01	26.4	H3PO4	52.1	17.0	H2SO4	2.78	0.910	H2O	31.1
24	NH3	14.34	27.37	H3PO4	46.9	15.6	H2SO4	7.95	2.63	H2O	30.8
25	NH3	14.42	26.35	H3PO4	44.5	14.1	H2SO4	8.99	2.85	H2O	32.1
26	NH3	14.19	26.53	H3PO4	43.6	14.2	H2SO4	10.8	3.49	H2O	31.4
27	NH3	14.39	27.66	H3PO4	43.8	14.6	H2SO4	11.2	3.74	H2O	30.6
28	NH3	10.74	17.61	H3PO4	28.6	8.14	H2SO4	24.9	7.08	H2O	35.8
29	NH3	9.93	17.6	H3PO4	34.0	10.5	H2SO4	23.0	7.10	H2O	33.1
30	NH3	9.12	15.3	H3PO4	35.8	10.5	H2SO4	20.2	5.90	H2O	34.9
31	NH3	7.32	11.7	H3PO4	42.8	11.9	H2SO4	13.1	3.63	H2O	36.8
32	NH3	11.73	18.52	H3PO4	0.0	0.0	H2SO4	51.1	14.0	H2O	37.2
33	NH3	11.6	19.2	H3PO4	3.26	0.936	H2SO4	49.6	14.2	H2O	35.5
34	NH3	11.45	19.52	H3PO4	4.75	1.41	H2SO4	49.4	14.6	H2O	34.4
35	NH3	11.3	19.9	H3PO4	8.49	2.59	H2SO4	46.8	14.3	H2O	33.4
36	NH3	11.3	21.5	H3PO4	13.8	4.56	H2SO4	44.0	14.5	H2O	30.9
37	NH3	11.3	21.8	H3PO4	14.6	4.90	H2SO4	43.6	14.6	H2O	30.5
38	NH3	12.23	41.72	H3PO4	0.0	0.0	H2SO4	70.6	41.8	H2O	17.2
39	NH3	12.57	51.45	H3PO4	2.53	1.80	H2SO4	70.6	50.1	H2O	14.3
40	NH3	12.1	53.6	H3PO4	6.12	4.71	H2SO4	68.5	52.7	H2O	13.2
41	NH3	11.8	53.8	H3PO4	8.62	6.82	H2SO4	66.7	52.8	H2O	12.9
42	NH3	11.3	21.8	H3PO4	14.6	4.90	H2SO4	43.6	14.6	H2O	30.5
43	NH3	10.59	19.99	H3PO4	14.0	4.58	H2SO4	44.3	14.5	H2O	31.1
44	NH3	10.1	21.1	H3PO4	10.6	3.83	H2SO4	51.2	18.6	H2O	28.1
45	NH3	11.8	52.3	H3PO4	8.62	6.63	H2SO4	66.3	51.0	H2O	13.3
46	NH3	10.74	17.61	H3PO4	28.6	8.14	H2SO4	24.9	7.08	H2O	35.8
47	NH3	11.01	19.44	H3PO4	24.6	7.55	H2SO4	31.1	9.55	H2O	33.2
48	NH3	10.9	20.2	H3PO4	18.1	5.82	H2SO4	39.3	12.6	H2O	31.7
49	NH3	11.0	20.6	H3PO4	16.4	5.36	H2SO4	41.3	13.5	H2O	31.3
50	NH3	11.3	21.8	H3PO4	14.6	4.90	H2SO4	43.6	14.6	H2O	30.5

Notes:
   Table 1  ^a  The solid phases are: A=(NH₄)₂SO₄; B=NH₄H₂PO₄; C=[NH₄H₂PO₄·NH₄HSO₄ (i.e. (NH₄)₂H₃(PO₄)(SO₄)-compilers]: D=(NH₄)₂HPO₄.
   Table 1  ^b  This is an obvious error. The compilers believe that the solid phase is A+D.
   Table 3  ^a  The solid phases are: A=(NH₄)₂SO₄; B=NH₄H₂PO₄; C=NH₄H₂PO₄·NH₄HSO₄. (i.e. (NH₄)₂H₃PO₄SO₄-compilers)]: D=(NH₄)₂HPO₄; E=(NH₄)H₃(SO₄)₂; F= NH₄HSO₄; G=(NH₄)₃H(SO₄)₂.

Method/Apparatus/Procedure:
   Nothing is stated. The compilers assume that some sort of the invariant points method was used.

Source and Purity of Materials:
   No information is given.

Estimated Errors:
   Solubility: nothing specified.
   Temperature: nothing specfied.

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