Compilation - Ammonia with Nitric acid, Phosphoric acid, Calcium oxide and Water (IUPAC SDS Volume 66)
SDS Volume (2970)
Volume 66. Ammonium Phosphates, p None
Original Measurements
Flatt, R.; Brunisholz, G.; Lauber, E.; Helv. Chim. Acta 1953, 36, 1971.
Variables:
Room Temp: 0, 25 and 50 °C
Prepared by:
Method/Apparatus/Procedure:
The eutonic solution existing in equilibrium with three salts - $\ce{Ca(H2PO4)2.H2O}$, $\ce{NH4H2PO4}$ and $\ce{Ca9(NH4)4H32(PO4)18.10H2O}$ - was prepared and saturated with $\ce{NH4NO3}$. 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 three weeks. The saturated solution was analyzed for $\ce{Ca^{2+}}$, $\ce{NH4^{+}}$, $\ce{H^{+}}$, $\ce{NO3^{-}}$ and $\ce{PO4^{3-}}$. 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.
Components:
- Ammonia, $\ce{ NH3 }$; [7664-41-7] NIST WebBook
- Nitric acid, $\ce{ HNO3 }$; [7697-37-2] NIST WebBook
- Phosphoric acid, $\ce{ H3PO4 }$; [7664-38-2] NIST WebBook
- Calcium oxide, $\ce{ CaO }$; [1305-78-8] NIST WebBook
- Water, $\ce{ H2O }$; [7732-18-5] NIST WebBook
Experimental Data
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 | 0.00 | 9.42 |
| 1.76 | 3.84 | 15.87 | 3.42 | 6.60 |
| 2.37 | 5.06 | 11.20 | 7.03 | 4.66 |
| 3.13 | 7.33 | 7.35 | 11.80 | 3.05 |
| 3.75 | 9.58 | 5.68 | 15.73 | 2.34 |
| 4.26 | 11.93 | 4.37 | 19.44 | 1.80 |
| 1.14 | 5.38 | 32.47 | 0.00 | 13.44 |
| 1.26 | 5.87 | 31.07 | 0.88 | 12.86 |
| 1.39 | 6.27 | 28.37 | 2.28 | 11.72 |
| 1.59 | 6.81 | 26.90 | 3.54 | 11.12 |
| 1.75 | 7.40 | 24.13 | 5.10 | 9.98 |
| 1.91 | 7.98 | 22.38 | 6.62 | 9.19 |
| 2.35 | 10.01 | 16.96 | 10.89 | 6.93 |
| 2.65 | 11.40 | 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 |
| 3.60 | 17.63 | 10.15 | 22.39 | 4.20 |
| 3.98 | 20.36 | 9.34 | 26.58 | 3.69 |
| 4.18 | 21.92 | 8.49 | 28.60 | 3.39 |
| 1.22 | 9.69 | 47.86 | 0.00 | 20.00 |
| 2.05 | 14.28 | 38.55 | 9.22 | 15.90 |
| 2.52 | 19.63 | 28.18 | 18.46 | 11.47 |
| 3.67 | 30.64 | 19.36 | 33.86 | 7.83 |
(a) The water content is expressed as mol/100 mol solute.
(b) The solid phases are: A = $\ce{Ca(H2PO4)2.H2O}$; B = $\ce{NH4H2PO4}$; C = $\ce{Ca9(NH4)4H32(PO4)18.10H2O}$; D = $\ce{NH4NO3}$
