SDS Volume
Volume 73. Metal and Ammonium Formate Systems, p None
Source Publication
Stoilova, D.; Balarew, C.; Vassileva, V.; Russeva, St.; Zh. Neorg. Khim. 26, 1641 (1981).
Conditions:
Room Temp: Composition at 50 °C
Compilers:
St. Trendafilova, Chr. Balarew
Methodology:
Equilibrium was reached in 15-20 hrs using the isothermal decrease of supersaturation method. The sum of the $\ce{Mg^{2+}}$ and $\ce{Co^{2+}}$ content of both phases was determined using Complexon III at pH 9-10 and Eriochrome Black T as indicator. $\ce{Co^{2+}}$ 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].
Sample Information:
- The cobalt and magnesium formates were prepared by reaction of the basic carbonates with formic acid solutions.
Measurement Errors:
Ambient temperature: Not given.
Mass concentration (m/v) (1): The solubilities were determined in a slight excess of formic acid.
Methodology Citation
1 Trendafelov, D.; Balarew, Chr.; Comm. Dept. Chem. Bulg. Acad. Sci. 1 , 73 (1968).
System Components:
- Magnesium formate, $\ce{ Mg(CHO2)2 }$; [557-39-1] NIST WebBook
- Cobalt formate, $\ce{ Co(CHO2)2 }$; [544-18-3] NIST WebBook
- Water, $\ce{ H2O }$; [7732-18-5] NIST WebBook
Experimental Data
| 100w2 | 100w1 | D1|2 | D2|1 | m2 (mol/kg) | m1 (mol/kg) | Phase (s) () |
|---|---|---|---|---|---|---|
| 3.33 | 0.00 | - | - | 0.231 | 0.00 | A |
| 1.93 | 2.13 | 0.02 | 50.0 | 0.135 | 0.194 | B |
| 1.49 | 3.24 | 0.02 | 50.0 | 0.105 | 0.297 | B |
| 1.35 | 5.06 | 0.06 | 16.67 | 0.097 | 0.473 | B |
| 0.72 | 6.89 | 0.04 | 25.0 | 0.052 | 0.652 | B |
| 0.57 | 8.58 | 0.04 | 25.0 | 0.042 | 0.826 | B |
| 0.38 | 10.04 | 0.04 | 25.0 | 0.028 | 0.980 | B |
| 0.12 | 12.23 | 0.03 | 33.34 | 9 x 10-3 | 1.220 | B |
| 0.05 | 12.98 | 0.03 | 33.34 | 4 x 10-3 | 1.305 | B |
| 0.00 | 13.90 | - | - | 0.00 | 1.412 | C |
(a) These values were calculated by the compilers.
(b) The solid phases are: A = Co(CHO2)2·2H2O; B = (Co,Mg)(CHO2)2·2H2O; C = Mg(CHO2)2·2H2O.
