SDS Volume (4611)
Volume 73. Metal and Ammonium Formate Systems, p None
Original Measurements
Stoilova, D.; Balarew, C.; Vassileva, V.; Russeva, St.; Zh. Neorg. Khim. 26, 1641 (1981).
Variables:
Room Temp: Composition at 80 °C
Prepared by:
St. Trendafilova, Chr. Balarew
Method/Apparatus/Procedure:
Equilibrium was reached in 15-20 hrs using the isothermal decrease of supersaturation method. The sum of the $\ce{Mg^{2+}}$ and $\ce{Zn^{2+}}$ content of both phases was determined using Complexon III at pH 9-10 and Eriochrome Black T as indicator. $\ce{Zn^{2+}}$ was determined using Complexon III at pH 5.5-6.0 with Xylenol Orange as indicator. The composition of the suction-dried mixed crystals was determined by the method of algebraic indirect identification of the solid phase [1].
Source and Purity of Materials:
- The zinc and magnesium formates were prepared by dissolving the normal or basic carbonates in dilute formic acid.
Estimated Errors:
Ambient temperature: Not given.
Mass concentration (m/v) (1): The solubilities were determined in a slight excess of formic acid.
References
1 Trendafelov, D.; Balarew, Chr.; Comm. Dept. Chem. Bulg. Acad. Sci. 1 , 73 (1968).
Components:
- Magnesium formate, $\ce{ Mg(CHO2)2 }$; [557-39-1] 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 Mg(CHO2)2-Zn(CHO2)2-H2O system at 80°C.
| 100w2 | 100w1 | D1|2 | D2|1 | m2 (mol/kg) | m1 (mol/kg) | Phase (s) () |
|---|---|---|---|---|---|---|
| 14.88 | 0.00 | - | - | 1.125 | 0.00 | A |
| 13.93 | 1.11 | 0.34 | 2.94 | 1.055 | 0.114 | B |
| 11.45 | 3.96 | 0.33 | 3.03 | 0.871 | 0.409 | B |
| 10.57 | 5.16 | 0.35 | 2.86 | 0.807 | 0.536 | B |
| 9.86 | 6.33 | 0.36 | 3.00 | 0.757 | 0.661 | B |
| 9.15 | 7.69 | 0.43 | 2.33 | 0.708 | 0.809 | B |
| 7.05 | 9.01 | 0.44 | 2.27 | 0.540 | 0.939 | B |
| 6.51 | 10.41 | 0.43 | 2.33 | 0.504 | 1.096 | B |
| 4.28 | 12.54 | 0.47 | 2.13 | 0.331 | 1.318 | B |
| 4.13 | 12.80 | 0.56 | 1.79 | 0.320 | 1.348 | B |
| 3.34 | 13.05 | 0.65 | 1.54 | 0.257 | 1.365 | B |
| 2.19 | 13.94 | 0.64 | 1.56 | 0.168 | 1.454 | B |
| 1.02 | 16.18 | 0.72 | 1.39 | 0.079 | 1.709 | B |
| 0.00 | 16.52 | - | - | 0.00 | 1.731 | C |
(a) The molality values were calculated by the compilers.
(b) The solid phases are: A = Zn(CHO2)2·2H2O; B = (Zn,Mg)(CHO2)2·2H2O; C = Mg(CHO2)2·2H2O.
