SDS Volume (4806)
Volume 73. Metal and Ammonium Formate Systems, p None
Original Measurements
Nadzharyan, K. A.; Itkina, L. S.; Russ. J. Inorg. Chem. 26, 595-8 (1981).
Variables:
Room Temp: Composition at 25 °C
Prepared by:
St. Trendafilova, Chr. Balarew
Method/Apparatus/Procedure:
The isothermal method was used. Equilibrium was reached in two weeks. The lithium content of both phases was determined by flame photometry. The $\ce{NH4^{+}}$ content was determined by the tetraphenylborate method. The composition of the solid phases was determined by Schreinemakers' method, by TG analysis, IR spectroscopy and X-ray diffraction.
Source and Purity of Materials:
- $\ce{LiCHO2.H2O}$ was prepared by neutralizing 85% formic acid with suprapure reagent grade $\ce{LiOH}$. Ammonium formate was prepared by passing $\ce{NH3}$ into 90% formic acid.
Estimated Errors:
Ambient temperature: The temperature was kept constant to within ±0.1°C.
Components:
- Lithium formate, $\ce{ LiCHO2 }$; [556-63-8] NIST WebBook
- Ammonium formate, $\ce{ NH4CHO2 }$; [540-69-2] NIST WebBook
- Water, $\ce{ H2O }$; [7732-18-5] NIST WebBook
Experimental Data
Solubility values in the LiCHO2-NH4CHO2-H2O system at 25°C.
| 100w1 | 100w2 | m1 (mol/kg) | m2 (mol/kg) | Phase (s) () |
|---|---|---|---|---|
| 27.99 | - | 7.481 | - | A |
| 21.05 | 17.59 | 6.602 | 4.546 | A |
| 21.67 | 20.56 | 7.219 | 5.644 | A |
| 21.39 | 29.34 | 8.355 | 9.443 | A |
| 19.95 | 34.79 | 8.483 | 12.19 | A |
| 21.37 | 41.44 | 11.06 | 17.67 | A |
| 22.76 | 44.40 | 13.34 | 21.44 | A + B |
| 21.65 | 45.09 | 12.53 | 21.50 | B |
| 17.65 | 45.22 | 9.149 | 19.31 | B |
| 10.52 | 47.51 | 4.824 | 17.95 | B |
| 5.26 | 49.98 | 2.26 | 17.70 | B |
| - | 60.53 | - | 24.32 | B |
(a) The solid phases are: A = LiCHO2·H2O ; B = NH4CHO2.
(b) The molality values were calculated by the compilers.
