Components:
(1) Ammonia,
NH3; [7664-41-7]
NIST WebBook
(2) Nitric acid,
HNO3; [7697-37-2]
NIST WebBook
(3) Phosphoric acid,
H3PO4; [7664-38-2]
NIST WebBook
(4) Calcium oxide,
CaO; [1305-78-8]
NIST WebBook
(5) Water,
H2O; [7732-18-5]
NIST WebBook
Original Measurements
Flatt, R.; Brunisholz, G.; Lauber, E.; Helv. Chim. Acta 1953, 36, 1971.
Variables:
Ambient temperature: Composition at 0 °C, 25 °C and 50 °C.
Prepared by:
Method/Apparatus/Procedure:
The eutonic solution existing in equilibrium with 3 salts--Ca(H2PO4)2·H2O, NH4H2PO4 and Ca9 (NH4)4H32(PO4)18·10H2O--was prepared and saturated with NH4NO3. The system was stirred in a thermostat and examined petrographically. When all the desired phases were present, the stirring was interrupted and the system was equilibrated for at least 3 weeks. The satd soln was analyzed for Ca2+, NH4+, H+, NO3– and PO43–. The analytical methods are not described.
Source and Purity of Materials:
- No information is given.
Estimated Errors:
Ambient temperature: The only information given is that the temperature 273 K was kept constant within ±0.1 K.
Experimental Values:
Part 1. The authors' data
Composition of saturated solutions coexisting with Ca(H2PO4)2·H2O, NH4H2PO4 and Ca9(NH4)4H32(PO4)18·10H2O
| T (°C) | 100x5 (solutes) | 100x4 (solutes) | 100x1 (solutes) | 100xH+ (solutes) | 100x2 (solutes) | 100x3 (solutes) | Phase (s)b |
|---|---|---|---|---|---|---|---|
| 0.0 | 196.5 | 8.45 | 10.93 | 80.62 | 0.0 | 100.0 | A + B + C |
| 0.0 | 239.1 | 15.18 | 16.53 | 68.29 | 14.73 | 85.27 | A + B + C |
| 0.0 | 264.6 | 22.56 | 24.1 | 53.34 | 33.46 | 66.54 | A + B + C |
| 0.0 | 265.2 | 29.9 | 35.01 | 35.09 | 56.35 | 43.65 | A + B + C |
| 0.0 | 244.2 | 32.94 | 42.09 | 24.97 | 69.14 | 30.86 | A + B + C |
| 0.0 | 223.8 | 34.33 | 48.05 | 17.62 | 78.3 | 21.7 | A + B + C + D |
| 25.0 | 137.8 | 5.64 | 13.83 | 80.53 | 0.0 | 100.0 | A + B + C |
| 25.0 | 140.8 | 6.37 | 14.88 | 78.75 | 2.22 | 97.78 | A + B + C |
| 25.0 | 148.4 | 7.45 | 16.76 | 75.79 | 6.09 | 93.91 | A + B + C |
| 25.0 | 150.6 | 8.6 | 18.47 | 72.93 | 9.6 | 90.4 | A + B + C |
| 25.0 | 158.6 | 9.98 | 21.12 | 68.9 | 14.57 | 85.43 | A + B + C |
| 25.0 | 162.5 | 11.18 | 23.35 | 65.47 | 19.35 | 80.65 | A + B + C |
| 25.0 | 175.4 | 14.86 | 31.6 | 53.54 | 34.39 | 65.61 | A + B + C |
| 25.0 | 176.3 | 16.8 | 36.18 | 47.02 | 42.96 | 57.04 | A + B + C |
| 25.0 | 173.8 | 17.56 | 38.81 | 43.63 | 46.9 | 53.1 | A + B + C |
| 25.0 | 169.6 | 19.82 | 45.58 | 34.6 | 57.92 | 42.08 | A + B + C |
| 25.0 | 158.8 | 20.59 | 50.39 | 29.02 | 64.0 | 36.0 | A + B + C |
| 25.0 | 147.5 | 21.15 | 54.06 | 24.79 | 70.57 | 29.43 | A + B + C |
| 25.0 | 143.3 | 21.55 | 56.54 | 21.91 | 73.78 | 26.22 | A + B + C + D |
| 50.0 | 92.6 | 4.08 | 16.15 | 79.77 | 0.0 | 100.0 | A + B + C |
| 50.0 | 97.6 | 7.2 | 25.08 | 67.72 | 16.19 | 83.81 | A + B + C |
| 50.0 | 105.1 | 9.54 | 37.14 | 53.32 | 34.93 | 65.07 | A + B + C |
| 50.0 | 96.9 | 12.79 | 53.45 | 33.76 | 59.05 | 40.95 | A + B + C |
(a) The water content is expressed as mol/100 mol solute. (b) The solid phases are: A = Ca(H2PO4)2·H2O; B = NH4H2PO4; C = Ca9(NH4)4H32(PO4)18·10H2O; D = NH4NO3
Part 2. The compiler has used the data in Part 1 to calculate the following concentration values. Values expressed as 100wi.
| 100w1 | 100w2 | 100w3 | w4 | 100w5 | 100w6 |
|---|---|---|---|---|---|
| 2.36 | 2.59 | 1.12 | 0.0 | 44.61 | 49.31 |
| 3.53 | 3.27 | 7.9 x 10-1 | 10.78 | 31.67 | 49.96 |
| 4.56 | 4.14 | 5.4 x 10-1 | 21.26 | 21.47 | 48.03 |
| 5.47 | 5.44 | 3.2 x 10-1 | 32.42 | 12.75 | 43.59 |
| 5.92 | 6.43 | 2.2 x 10-1 | 39.11 | 8.86 | 39.45 |
| 6.15 | 7.32 | 1.6 x 10-1 | 44.13 | 6.21 | 36.03 |
| 1.85 | 3.86 | 1.32 | 0.0 | 52.38 | 40.6 |
| 2.04 | 4.05 | 1.26 | 2.23 | 49.96 | 40.47 |
| 2.27 | 4.34 | 1.15 | 5.84 | 45.74 | 40.65 |
| 2.55 | 4.65 | 1.08 | 8.94 | 42.74 | 40.05 |
| 2.8 | 5.04 | 9.7 x 10-1 | 12.87 | 38.31 | 40.01 |
| 3.02 | 5.36 | 8.8 x 10-1 | 16.45 | 34.82 | 39.46 |
| 3.58 | 6.47 | 6.4 x 10-1 | 26.07 | 25.25 | 37.98 |
| 3.87 | 7.08 | 5.4 x 10-1 | 31.1 | 20.97 | 36.45 |
| 3.98 | 7.48 | 4.9 x 10-1 | 33.44 | 19.22 | 35.39 |
| 4.29 | 8.38 | 3.7 x 10-1 | 39.43 | 14.55 | 32.98 |
| 4.42 | 9.18 | 3.1 x 10-1 | 43.17 | 12.33 | 30.59 |
| 4.5 | 9.78 | 2.6 x 10-1 | 47.24 | 10.0 | 28.2 |
| 4.55 | 10.15 | 2.3 x 10-1 | 49.02 | 8.85 | 27.2 |
| 1.54 | 5.19 | 1.5 | 0.0 | 60.34 | 31.43 |
| 2.37 | 7.0 | 1.11 | 16.73 | 43.98 | 28.81 |
| 2.71 | 8.97 | 7.6 x 10-1 | 31.21 | 29.53 | 26.83 |
| 3.21 | 11.41 | 4.2 x 10-1 | 46.66 | 16.43 | 21.87 |
The following values are expressed as m1/ mol kg-1.
| m1 (mol/kg) | m2 (mol/kg) | m3 (mol/kg) | m4 (mol/kg) | m5 (mol/kg) |
|---|---|---|---|---|
| 1.19 | 3.09 | 22.79 | 0.0 | 9.42 |
| 1.76 | 3.84 | 15.87 | 3.42 | 6.6 |
| 2.37 | 5.06 | 11.2 | 7.03 | 4.66 |
| 3.13 | 7.33 | 7.35 | 11.8 | 3.05 |
| 3.75 | 9.58 | 5.68 | 15.73 | 2.34 |
| 4.26 | 11.93 | 4.37 | 19.44 | 1.8 |
| 1.14 | 5.38 | 32.47 | 0.0 | 13.44 |
| 1.26 | 5.87 | 31.07 | 8.8 x 10-1 | 12.86 |
| 1.39 | 6.27 | 28.37 | 2.28 | 11.72 |
| 1.59 | 6.81 | 26.9 | 3.54 | 11.12 |
| 1.75 | 7.4 | 24.13 | 5.1 | 9.98 |
| 1.91 | 7.98 | 22.38 | 6.62 | 9.19 |
| 2.35 | 10.01 | 16.96 | 10.89 | 6.93 |
| 2.65 | 11.4 | 14.82 | 13.54 | 5.99 |
| 2.81 | 12.41 | 13.95 | 14.99 | 5.66 |
| 3.25 | 14.93 | 11.33 | 18.97 | 4.59 |
| 3.6 | 17.63 | 10.15 | 22.39 | 4.2 |
| 3.98 | 20.36 | 9.34 | 26.58 | 3.69 |
| 4.18 | 21.92 | 8.49 | 28.6 | 3.39 |
| 1.22 | 9.69 | 47.86 | 0.0 | 20.0 |
| 2.05 | 14.28 | 38.55 | 9.22 | 15.9 |
| 2.52 | 19.63 | 28.18 | 18.46 | 11.47 |
| 3.67 | 30.64 | 19.36 | 33.86 | 7.83 |
