SDS Volume (4629)
Volume 73. Metal and Ammonium Formate Systems, p None
Original Measurements
Balarew, C.; Stoilova, D. G.; Vassileva, V. Z.; Dokl. Bolg. Akad. Nauk 35, 933 (1982).
Variables:
Room Temp: Composition at 25 °C
Prepared by:
St. Trendafilova, Chr. Balarew
Method/Apparatus/Procedure:
Equilibrium was reached after about two days of stirring using the isothermal decrease of supersaturation method. The sum of the $\ce{Mn^{2+}}$ and $\ce{Cd^{2+}}$ content of both phases was determined complexometrically with Complexon III at pH 9.5-10, using Eriochrome Black T as indicator after adding hydroxylamine hydrochloride. $\ce{Mn^{2+}}$ in the presence of $\ce{Cd^{2+}}$ was determined the same way after binding the $\ce{Cd^{2+}}$ as cyanide complexes. 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 manganese and cadmium formates were prepared by the reaction of dilute formic acid with manganese and cadmium carbonates, respectively. All reagents were p.a. grade.
Estimated Errors:
Ambient temperature: Not given.
Mass concentration (m/v) (1): The solubilities were determined in a slight excess of formic acid (about 2%) in order to inhibit hydrolysis.
References
1 Trendafelov, D.; Balarew, Chr.; Comm. Dept. Chem. Bulg. Acad. Sci. 1 , 73 (1968).
Components:
- Manganese(II) formate, $\ce{ Mn(CHO2)2 }$; [3251-96-5] NIST WebBook
- Cadmium formate, $\ce{ Cd(CHO2)2 }$; [4464-23-7] NIST WebBook
- Water, $\ce{ H2O }$; [7732-18-5] NIST WebBook
Experimental Data
Solubility values in the Mn(CHO2)2-Cd(CHO2)2-H2O system at 25°C.
| 100w1 | 100w2 | D2|1 | D1|2 | m1 (mol/kg) | m2 (mol/kg) | Phase (s) () |
|---|---|---|---|---|---|---|
| 6.28 | - | - | - | 0.462 | - | A |
| 5.83 | 1.22 | 0.63 | 1.59 | 0.433 | 0.065 | B |
| 5.59 | 2.17 | 0.84 | 1.19 | 0.418 | 0.116 | B |
| 5.05 | 3.21 | 1.00 | 1.00 | 0.380 | 0.173 | B |
| 4.73 | 3.57 | 0.92 | 1.09 | 0.356 | 0.192 | B |
| 3.71 | 6.00 | 0.87 | 1.15 | 0.283 | 0.328 | B |
| 2.59 | 8.35 | 0.86 | 1.16 | 0.201 | 0.463 | B |
| 2.19 | 9.01 | 0.94 | 1.06 | 0.170 | 0.501 | B |
| 1.15 | 10.96 | 0.79 | 1.27 | 0.090 | 0.616 | B |
| 0.00 | 12.45 | - | - | 0.00 | 0.703 | C |
(a) The molality values were calculated by the compilers.
(b) The solid phases are: A = Mn(CHO2)2·2H2O; B = (Mn,Cd)(CHO2)2·2H2O; C = Cd(CHO2)2·2H2O.
