SDS Volume (2902)
Volume 66. Ammonium Phosphates, p None
Original Measurements
Treshchov, A. G.; Dokl. Timiryazevsk. S. -kh. Akad. 29, 402 (1957).
Variables:
Temperature and composition.
Prepared by:
Method/Apparatus/Procedure:
A visual polythermic method was used.
Source and Purity of Materials:
- No information is given.
Estimated Errors:
Ambient temperature: No information is given.
Mass concentration (m/v) (1): No information is given.
Components:
- Diammonium hydrogenphosphate, $\ce{ (NH4)2HPO4 }$; [7783-28-0] NIST WebBook
- Urea, $\ce{ CH4N2O }$; [57-13-6] NIST WebBook
- Water, $\ce{ H2O }$; [7732-18-5] NIST WebBook
Experimental Data
Monovariant and invariant points in the (NH4)2HPO4-CO(NH2)2-H2O system
| $T$ (°C) | 100w1 | 100w2 | 100w3 | $100 x_{3} (\rm{solutes})$ (mol/100 mol) | m1 (mol/kg) | m2 (mol/kg) | Phase (s) () |
|---|---|---|---|---|---|---|---|
| -11 | 32.90 | 0.00 | 67.10 | 6.8E+2 | 8.16 | 0.00 | A + B |
| 1.1 | 40.70 | 0.00 | 59.30 | 489 | 11.43 | 0.00 | B + C |
| 24.4 | 54.50 | 0.00 | 45.50 | 279 | 19.94 | 0.00 | C + D |
| -6.7 | 0.00 | 29.60 | 70.40 | 1.73 x 103 | 0.00 | 3.18 | A + E |
| -8.6 | 0.00 | 4.60 | 95.40 | 1.397 x 103 | 0.00 | 0.37 | E + F(metastable) |
| -17.0 | 25.40 | 12.30 | 62.30 | 6.7E+2 | 6.79 | 1.49 | A + B + E |
| -16.2 | 26.70 | 15.90 | 57.40 | 563 | 7.74 | 2.10 | B + E + F |
(a) These values were calculated by the compilers.
(b) The composition unit is: mol/100 mol of solute.
(c) The solid phases are: A = ice: B = α-CO(NH2)2; C = β-CO(NH2)2; D = γ-CO(NH2)2; E = (NH4)2HPO4·2H2O; F = (NH4)2HPO4.
