IUPAC-NIST Solubilities Database

IUPAC-NIST Solubility Database
NIST Standard Reference Database 106

Solubility System: Ammonium dihydrogenphosphate with Ammonium chloride, Potassium dihydrogenphosphate, Potassium chloride and Water

Components:
   (1) Ammonium chloride; NH4Cl; [12125-02-9]  NIST Chemistry WebBook for detail
   (2) Ammonium dihydrogenphosphate; NH4H2PO4; [7722-76-1]  NIST Chemistry WebBook for detail
   (3) Potassium chloride; KCl; [7747-40-7]  NIST Chemistry WebBook for detail
   (4) Potassium dihydrogenphosphate; KH2PO4; [7778-77-0]  NIST Chemistry WebBook for detail
   (5) Water; H2O; [7732-18-5]  NIST Chemistry WebBook for detail

Original Measurements:
   Polosin, V.A.; Shakhparonov, M.I., Zh. Fiz. Khim. 21, 119 (1947).

Variables:

   Concentration = Composition and temperature.

Prepared By:
   J. Eysseltová

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

Part 1. Solubility isotherms in the (NH₄)₃PO₄-H₃PO₄-Ca₃(PO₄)₂-H₂O system with the ratio NH₃/H₃PO₄ = 0.5.
t/°C	Chemical₁	Composition₁^(a)	10² * Mass Fraction w₁	m₁ [mol/kg]^(b)	Chemical₂	Composition₂^(a)	10² * Mass Fraction w₂	m₂ [mol/kg]^(b)	Chemical₃	Composition₃^(a)	10² * Mass Fraction w₃	Solid Phase(s)^(c)
-10	KCl	100.0	19.10	3.171	NH4H2PO4	0.00	0.00	0.00	H2O	1744	80.90	A
-10	KCl	94.40	17.75	2.954	NH4H2PO4	5.60	1.65	0.178	H2O	1772	80.60	A
-10	KCl	84.40	19.12	3.242	NH4H2PO4	5.60d	1.78	0.196	H2O	1613	79.10	B
-10	KCl	100.0	9.80	1.46	NH4H2PO4	0.00	0.00	0.00	H2O	1668	90.20	C
0	KCl	100.0	21.65	3.707	NH4H2PO4	0.00	0.00	0.00	H2O	1496	78.35	C
0	KCl	94.40	21.32	3.728	NH4H2PO4	5.60	1.98	0.224	H2O	1404	76.70	B
0	KCl	91.20	19.00	3.260	NH4H2PO4	8.80	2.83	0.315	H2O	1552	78.17	D
0	KCl	77.60	11.76	1.900	NH4H2PO4	22.40	5.24	0.549	H2O	2266	83.00	D
0	KCl	58.00	8.20	1.33	NH4H2PO4	42.00	9.18	0.966	H2O	2415	82.62	D
0	KCl	40.00	6.10	1.02	NH4H2PO4	60.00	14.08	1.533	H2O	2170	79.82	D
0	KCl	17.00	2.39	0.402	NH4H2PO4	83.00	17.81	1.940	H2O	2371	79.80	D
0	KCl	0.00	0.00	0.00	NH4H2PO4	100.0	18.50	1.973	H2O	2813	81.50	E
10	KCl	100.0	23.50	4.120	NH4H2PO4	0.00	0.00	0.00	H2O	1348	76.50	C
10	KCl	94.40	23.33	4.200	NH4H2PO4	5.60	2.17	0.253	H2O	1246	74.50	F
10	KCl	93.00	23.10	4.175	NH4H2PO4	7.60d	2.69	0.315	H2O	1226	74.21	F
10	KCl	77.60	13.56	2.262	NH4H2PO4	22.40	6.04	0.653	H2O	1903	80.40	D
10	KCl	65.40	10.90	1.823	NH4H2PO4	34.60	8.91	0.966	H2O	1991	80.19	D
10	KCl	47.50	8.10	1.39	NH4H2PO4	52.50	13.78	1.533	H2O	1898	78.12	D
10	KCl	32.20	5.00	1.03	NH4H2PO4	67.80	18.84	2.173	H2O	1734	75.36	D
10	KCl	17.00	2.85	0.504	NH4H2PO4	83.00	21.25	2.434	H2O	1890	75.90	D
10	KCl	0.00	0.00	0.00	NH4H2PO4	100.0	22.10	2.466	H2O	2251	77.90	E
20	KCl	100.0	25.70	4.639	NH4H2PO4	0.00	0.00	0.00	H2O	1195	74.30	C
20	KCl	94.40	24.89	4.586	NH4H2PO4	5.60	2.31	0.276	H2O	1135	72.80	F
20	KCl	90.40	22.63	4.120	NH4H2PO4	9.60	3.70	0.437	H2O	1218	73.67	F
20	KCl	77.60	15.36	2.648	NH4H2PO4	22.40	6.84	0.764	H2O	1625	77.80	D
20	KCl	71.00	13.70	2.366	NH4H2PO4	29.00	8.63	0.966	H2O	1666	77.67	D
20	KCl	53.90	10.20	1.792	NH4H2PO4	46.10	13.47	1.534	H2O	1671	76.33	D
20	KCl	40.10	8.00	1.46	NH4H2PO4	59.90	18.40	2.173	H2O	1529	73.60	D
20	KCl	20.00	3.90	0.726	NH4H2PO4	90.00d	24.02	2.897	H2O	1533	72.08	D
20	KCl	17.00	3.30	0.615	NH4H2PO4	83.00	24.70	2.982	H2O	1544	72.00	D
20	KCl	0.00	0.00	0.00	NH4H2PO4	100.0	26.30	3.102	H2O	1789	73.70	E
25	KCl	100.0	26.50	4.836	NH4H2PO4	0.00	0.00	0.00	H2O	1147	73.50	G
25	KCl	94.40	25.62	4.772	NH4H2PO4	5.60	2.38	0.287	H2O	1096	72.00	F
25	KCl	91.10	25.00	4.709	NH4H2PO4	8.90	3.80	0.464	H2O	1072	71.20	F
25	KCl	89.70	22.56	4.120	NH4H2PO4	10.30	4.00	0.473	H2O	1208	73.44	D
25	KCl	77.60	16.26	2.851	NH4H2PO4	22.44d	7.24	0.823	H2O	1510	76.50	D
25	KCl	73.30	15.00	2.630	NH4H2PO4	26.70	8.50	0.966	H2O	1544	76.50	D
25	KCl	56.70	11.30	2.010	NH4H2PO4	43.30	13.30	1.533	H2O	1567	75.40	D
25	KCl	43.50	9.10	1.68	NH4H2PO4	56.50	18.18	2.173	H2O	1441	72.72	D
25	KCl	29.60	6.40	1.32	NH4H2PO4	70.40	28.40	3.787	H2O	1347	65.20	D
25	KCl	17.00	3.54	0.678	NH4H2PO4	83.00	26.46	3.286	H2O	1401	70.00	D
25	KCl	0.00	0.00	0.00	NH4H2PO4	100.0	28.40	3.448	H2O	1476	71.60	E
35	KCl	100.0	27.70	5.138	NH4H2PO4	0.00	0.00	0.00	H2O	1077	72.30	G
35	KCl	94.40	27.17	5.184	NH4H2PO4	5.60	2.53	0.313	H2O	1010	70.30	F
35	KCl	90.70	24.96	4.712	NH4H2PO4	9.30	4.00	0.489	H2O	1067	71.04	D
35	KCl	86.90	22.28	4.121	NH4H2PO4	13.10	5.20	0.623	H2O	1170	72.52	D
35	KCl	77.60	18.00	3.262	NH4H2PO4	22.40	8.00	0.940	H2O	1320	74.00	D
35	KCl	77.00	17.80	3.227	NH4H2PO4	23.00	8.22	0.966	H2O	1323	73.98	D
35	KCl	62.60	14.00	2.569	NH4H2PO4	37.40	12.90	1.534	H2O	1353	73.10	D
35	KCl	49.30	11.40	2.157	NH4H2PO4	50.20	17.72	2.173	H2O	1282	70.88	D
35	KCl	39.60	9.60	1.899	NH4H2PO4	60.40	22.60	2.898	H2O	1152	67.80	D
35	KCl	17.00	4.01	0.717	NH4H2PO4	83.00	20.99	2.433	H2O	1165	75.00	D

Part 2. Monovariant and invariant points
t/°C	Chemical₁	Composition₁^(a)	10² * Mass Fraction w₁	m₁^(b)	Chemical₂	Composition₂^(a)	10² * Mass Fraction w₂	m₂^(b)	Chemical₃	Composition₃^(a)	10² * Mass Fraction w₃	Solid Phase(s)^(c)
-10.4	KCl	100.0	19.80	3.311	NH4H2PO4	0.00	0.00	0.00	H2O	1680	80.20	A + C
22.2	KCl	100.0	26.20	4.761	NH4H2PO4	0.00	0.00	0.00	H2O	1165	73.80	B + F
-2.4	KCl	0.00	0.00	0.00	NH4H2PO4	100.0	17.30	1.819	H2O	3053	82.70	A + E
-11.2	KCl	92.40	18.40	3.114	NH4H2PO4	7.60	2.35	0.258	H2O	1645	79.25	A + B + E
12.5	KCl	91.70	22.30	4.012	NH4H2PO4	8.30	3.15	0.367	H2O	1267	74.55	B + D + F
-11.0	KCl	94.40	18.80	3.176	NH4H2PO4	5.60	1.80	0.197	H2O	1645	79.40	A + B
8.0	KCl	94.40	23.05	4.133	NH4H2PO4	5.60	2.15	0.250	H2O	1266	74.80	B + Fd
-4.9	KCl	17.00	2.15	0.353	NH4H2PO4	83.00	16.05	1.706	H2O	2698	81.80	A + D
-5.0	KCl	25.30	3.20	0.522	NH4H2PO4	74.70	14.52	1.534	H2O	2701	82.28	A + D
-5.7	KCl	52.20	6.60	1.05	NH4H2PO4	47.80	9.34	0.966	H2O	2750	84.06	A + D
-6.5	KCl	77.60	10.52	1.664	NH4H2PO4	22.40	4.68	0.480	H2O	2589	84.80	A + D
-8.6	KCl	88.50	14.90	2.434	NH4H2PO4	11.50	2.98	0.315	H2O	2020	82.12	A + D
2.7	KCl	92.50	21.80	3.875	NH4H2PO4	7.50	2.74	0.316	H2O	1324	75.46	B + D
9.8	KCl	61.30e	22.70	4.117	NH4H2PO4	8.70	3.35	0.394	H2O	1230	73.95	D + F
24.0	KCl	91.10	25.00	4.709	NH4H2PO4	8.90	3.80	0.464	H2O	1072	71.20	D + F

Notes:
   Table 1  ^a  The composition unit is: mol/100 mol of solute.
   Table 1  ^b  These values were calculated by the compiler based on the mass % values of the components.
   Table 1  ^c  The solid phases are: A=ice; B=α-(NH₄,K)Cl; C=α-KCl; D=(NH₄,K)H₂PO₄; E=NH₄H₂PO₄; F=β-(NH₄,K)Cl; G= β-KCl.
   Table 1  ^d  This is an obvious error.
   Table 2  ^a  The composition unit is: mol/100 mol of solute.
   Table 2  ^b  The molalities were calculated by the compiler and are based on the mass % values of the components.
   Table 2  ^c  The solid phases are: A=ice; B=α-(NH₄,K)Cl; C=α,KCl; D=(NH₄,K)H₂PO₄; E=NH₄H₂PO₄ F=β-(NH₄,K)Cl; G=β,KCl.
   Table 2  ^d  In this line, the expression "β-(NH₄H₂K)Cl" stands for one of the solid phases. The compiler believes that this is an error.
   Table 2  ^e  This is obviously an error. The correct value is 91.30.

Method/Apparatus/Procedure:
   A polythermic method was used. Solid carbon dioxide served as the cooling agent.

Source and Purity of Materials:
   All materials were recrystallized twice and analyzed before being used. No further details are given.

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