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:
   Berlin, L.E.; Mantsev, B.M., Zh. Prikl. Khim. (Leningrad) 1933, 6, 385.; Vol'fkovich, S.I.; Berlin, L.E.; Mantsev, B.M., Tr. NIUIFa 1940, 228.

Variables:

   Concentration = Composition at 25 ºC

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

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

Solubility in the NH₃-P₂O₅-SO₃-H₂O system at 25 °C.

Solution number	Chemical1	Composition1 [mol/1000 mol H2O](a)	103 * Mass Fraction w1(b)	Chemical2	Composition2 [mol/1000 mol H2O](a)	103 * Mass Fraction w2(b)	Chemical3	Composition3 [mol/1000 mol H2O](a)	103 * Mass Fraction w3(b)	Solid Phase(s)(c)
1	NH3	57.4	4.23	P2O5	29.9	18.1	SO3	---	---	A
2	NH3	60.7	4.27	P2O5	36.3	21.3	SO3	---	---	A
3	NH3	171.1	10.7	P2O5	41.4	23.2	SO3	---	---	B
4	NH3	57.4	4.9	P2O5	9.55	6.66	SO3	---	---	C1
5	NH3	77.8	6.7	P2O5	3.16	2.29	SO3	---	---	C3
6	NH3	185.9	11.0	P2O5	---	---	SO3	94.5	26.4	D
7	NH3	185.8	9.10	P2O5	45.5	18.6	SO3	88.9	20.4	E
8	NH3	246.3	12.5	P2O5	81.4	34.2	SO3	---	---	A + B
9	NH3	201.5	11.3	P2O5	13.1	6.08	SO3	89.6	23.6	A + D
10	NH3	215.1	10.2	P2O5	44.4	17.6	SO3	98.6	22.0	A + E
11	NH3	166.8	10.7	P2O5	40.4	21.7	SO3	---	---	B + C3
12	NH3	230.0	12.5	P2O5	21.2	9.64	SO3	78.4	20.1	B + D
13	NH3	177.3	10.8	P2O5	6.0	3.09	SO3	72.1	20.9	C3 + D
14	NH3	216.1	13.3	P2O5	1.14	0.59	SO3	73.0	21.1	C3 + D
15 (d)	NH3	235.2	11.6	P2O5	---	---	SO3	156.2	36.2	D + F
16 (d)	NH3	542.6	11.3	P2O5	---	---	SO3	552.8	54.3	F + G
17	NH3	270.4	13.3	P2O5	55.2	22.7	SO3	51.0	12.0	A + B + D
18	NH3	231.3	12.8	P2O5	14.8	6.85	SO3	83.1	21.8	B + C3 + D
19	NH3	216.2	10.4	P2O5	39.8	16.0	SO3	101.6	22.9	D + E + F
20 (d)	NH3	242.2	11.1	P2O5	19.9	7.45	SO3	151.8	32.7	D + E + F
21	NH3	243.6	9.72	P2O5	19.9	6.62	SO3	220.8	41.5	E + F + G

Part 2. The compiler have used the data in Part 1 to calculated the following values.

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	4.21	3.50	H3PO4	25.2	3.65	H2SO4	0	0	H2O	70.6
2	NH3	4.27	3.78	H3PO4	29.4	4.53	H2SO4	0	0	H2O	66.3
3	NH3	10.88	10.85	H3PO4	30.3	5.25	H2SO4	0	0	H2O	58.8
4	NH3	4.81	3.28	H3PO4	9.21	1.09	H2SO4	0	0	H2O	86.0
5	NH3	6.70	4.36	H3PO4	3.13	0.354	H2SO4	0	0	H2O	90.2
6	NH3	11.02	11.41	H3PO4	0	0	H2SO4	32.3	5.80	H2O	56.7
7	NH3	9.108	13.33	H3PO4	25.7	6.53	H2SO4	25.1	6.38	H2O	40.1
8	NH3	12.43	18.11	H3PO4	47.3	2.0	H2SO4	0	0	H2O	40.3
9	NH3	11.26	12.85	H3PO4	8.43	1.67	H2SO4	28.8	5.71	H2O	51.5
10	NH3	10.21	15.56	H3PO4	24.3	6.42	H2SO4	27.0	7.13	H2O	38.5
11	NH3	10.69	10.55	H3PO4	29.8	5.11	H2SO4	0	0	H2O	59.5
12	NH3	12.55	14.89	H3PO4	13.3	2.75	H2SO4	24.6	5.08	H2O	49.5
13	NH3	10.92	10.83	H3PO4	4.25	0.733	H2SO4	25.6	4.40	H2O	59.2
14	NH3	13.29	13.00	H3PO4	0.807	0.137	H2SO4	25.9	4.39	H2O	60.0
15	NH3	11.61	15.49	H3PO4	0	0	H2SO4	44.39	10.29	H2O	44.00
16	NH3	12.92	67.45	H3PO4	0	0	H2SO4	75.83	68.72	H2O	11.25
17	NH3	13.34	19.18	H3PO4	31.3	7.83	H2SO4	14.5	3.62	H2O	40.8
18	NH3	12.83	14.73	H3PO4	9.45	1.88	H2SO4	26.6	5.297	H2O	51.2
19	NH3	10.38	15.42	H3PO4	22.0	5.68	H2SO4	28.10	7.24	H2O	39.5
20	NH3	11.12	17.07	H3PO4	10.5	2.80	H2SO4	40.13	10.70	H2O	38.2
21	NH3	9.726	18.81	H3PO4	9.14	3.074	H2SO4	50.77	17.05	H2O	30.6

Notes:
   Table 1  ^a  The composition unit is: mol/1000 mol H₂O.
   Table 1  ^b  This is an obvious error. The compilers believe that this should be 100 w_i.
   Table 1  ^c  The solid phases are: A=NH₄H₂PO₄; B=(NH₄)₂HPO₄; C₁=(NH₄)₃PO₄·H₂O; C₃=(NH₄)₃PO₄·3H₂O; D=(NH₄)₂SO₄; E=NH₄H₂PO₄·NH₄HSO₄; F=(NH₄)₃H(SO₄)₂; G=NH₄HSO₄.
   Table 1  ^d  These data appear in source paper (2) only.

Method/Apparatus/Procedure:
   The isothermal method was used. Equilibration required 4 days to 5 days. The composition of the solid phases was determined by the Schreinemakers method after removing the liquid from the surface

Source and Purity of Materials:
   No information is given.

Estimated Errors:

   Temperature: The temperature was kept constant within ±0.05 K. No other information is given.

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