SDS Volume (2930)
Volume 66. Ammonium Phosphates, p None
Original Measurements
Bergman, A. G.; Tashtemirov, R.; Ukr. Khim. Zh. 1967, 33, 565.
Variables:
Temperature and composition.
Prepared by:
Method/Apparatus/Procedure:
A visual polythermic method was used. A mixture of solid carbon dioxide and acetone was used as the cooling agent.
Source and Purity of Materials:
- Reagent grade $\ce{NH4H2PO4}$ was used. It had a melting point of 200°C.
Estimated Errors:
Ambient temperature: No information is given.
Mass concentration (m/v) (1): No information is given.
Components:
- Ammonium dihydrogenphosphate, $\ce{ NH4H2PO4 }$; [7722-76-1] NIST WebBook
- Water, $\ce{ H2O }$; [7732-18-5] NIST WebBook
Experimental Data
Solubility in the NH4H2PO4-H2O system.
| $T$ (°C) | 100w1 | m1 (mol/kg) | Phase (s) () |
|---|---|---|---|
| -2 | 1E+1 | 0.966 | A |
| -4 | 17 | 1.78 | A |
| -4.5 | 18 | 1.91 | A + B |
| -1.6 | 19 | 2.04 | B |
| 2.5 | 2E+1 | 2.17 | B |
| 9.5 | 22.5 | 2.52 | B |
| 22.5 | 27.5 | 3.30 | B |
| 32.5 | 32.5 | 4.19 | B |
| 35.5 | 34 | 4.48 | B + C |
| 39 | 35 | 4.68 | C |
| 46.5 | 37.5 | 5.22 | C |
| 51.5 | 4E+1 | 5.80 | C |
(a) The molalities were calculated by the compiler.
(b) The solid phases are: A = ice; B = α-NH4H2PO4; C = β-NH4H2PO4.
