SDS Volume (4824)
Volume 73. Metal and Ammonium Formate Systems, p None
Original Measurements
Itkina, L. S.; Nadzharyan, K. A.; Zh. Neorg. Khim. 24, 2283-5 (1979).
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 1-2 weeks. The lithium content of both phases was determined by flame photometry. The zinc content was determined complexometrically. The composition of the solid phases was determined by Schreinemakers' method.
Source and Purity of Materials:
- $\ce{LiCHO2.H2O}$ was prepared by neutralizing 85% formic acid with suprapure reagent grade $\ce{LiOH}$. The crystals were washed with alcohol and dried at 105°C over $\ce{H2SO4}$ in a vacuum. $\ce{Zn(CHO2)2.2H2O}$ was prepared by the reaction of 85% PA grade formic acid with $\ce{ZnO}$. It was recrystallized twice from 1% formic acid and dried at 105°C.
Estimated Errors:
Ambient temperature: The temperature was kept constant to within ±0.05°C.
Components:
- Lithium formate, $\ce{ LiCHO2 }$; [556-63-8] NIST WebBook
- Zinc formate, $\ce{ Zn(CHO2)2 }$; [557-41-5] NIST WebBook
- Water, $\ce{ H2O }$; [7732-18-5] NIST WebBook
Experimental Data
Solubility values in the LiCHO2-Zn(CHO2)2-H2O system at 25°C.
| 100w1 | 100w2 | m1 (mol/kg) | m2 (mol/kg) | Phase (s) () |
|---|---|---|---|---|
| - | 5.38 | - | 0.366 | A |
| 3.05 | 3.01 | 0.625 | 0.206 | A |
| 6.23 | 2.26 | 1.31 | 0.158 | A |
| 9.76 | 1.90 | 2.13 | 0.138 | A |
| 15.17 | 1.90 | 3.520 | 0.147 | A |
| 21.11 | 2.33 | 5.307 | 0.196 | A |
| 26.63 | 2.93 | 7.276 | 0.267 | A |
| 27.55 | 2.86 | 7.620 | 0.264 | A + B |
| 26.50 | 1.82 | 7.115 | 0.163 | B |
| 27.99 | - | 7.481 | - | B |
(a) The solid phases are: A = Zn(CHO2)2·2H2O; B = LiCHO2·H2O.
(b) The molality values were calculated by the compilers.
