SDS Volume (4641)
Volume 73. Metal and Ammonium Formate Systems, p None
Original Measurements
Balarew, C. C.; Vassileva, V. Z.; Compt. Rend. Acad. Bulg. Sci. 43, 51-4 (1990).
Variables:
Room Temp: Composition at 25 °C
Prepared by:
St. Trendafilova, Chr. Balarew
Method/Apparatus/Procedure:
The method used was the isothermal decrease of supersaturation, for 15-20 hrs. The $\ce{Ni^{2+}}$ content of the liquid and solid phases was determined gravimetrically with dimethylglyoxime. The sum of $\ce{Ni^{2+}}$ and $\ce{Zn^{2+}}$ was determined complexometrically by back titration in excess of Complexon III with $\ce{ZnSO4}$ at pH 5.5-6 using Xylenol Orange as indicator. The composition of the suction-dried mixed crystals was determined by the algebraic indirect identification of the solid phase composition method [1].
Source and Purity of Materials:
- The reagents used were of p.a. grade. Nickel and zinc formates were prepared by the action of dilute formic acid with nickel and zinc carbonates, respectively.
Estimated Errors:
Ambient temperature: Not given.
Mass concentration (m/v) (1): The solubility of the salts was determined in a slight excess of formic acid (about 2%) to suppress salt hydrolysis.
References
1 Trendafelov, D.; Balarew, Chr.; Comm. Dept. Chem. Bulg. Acad. Sci. 1 , 73 (1968).
Components:
- Nickel formate, $\ce{ Ni(CHO2)2 }$; [3349-06-2] 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 Ni(CHO2)2-Zn(CHO2)2-H2O system at 25°C.
| 100w1 | 100w2 | D2|1 | D1|2 | m1 (mol/kg) | m2 (mol/kg) | Phase (s) () |
|---|---|---|---|---|---|---|
| 2.14 | - | - | - | 0.146 | - | A |
| 1.75 | 0.75 | 0.59 | 1.68 | 0.121 | 0.049 | B |
| 1.18 | 1.45 | 0.58 | 1.73 | 0.081 | 0.096 | B |
| 1.06 | 1.80 | 0.55 | 1.80 | 0.073 | 0.119 | B |
| 0.76 | 2.50 | 0.39 | 2.59 | 0.053 | 0.166 | B |
| 0.42 | 3.28 | 0.20 | 4.89 | 0.029 | 0.219 | B |
| 0.19 | 3.60 | 0.12 | 8.37 | 0.013 | 0.241 | B |
| 0.06 | 4.42 | 0.11 | 8.86 | 4 x 10-3 | 0.298 | B |
| - | 5.38 | - | - | - | 0.366 | C |
(a) The molality values were calculated by the compilers.
(b) The solid phases are: A = Ni(CHO2)2·2H2O; B = (Ni,Zn)(CHO2)2·2H2O; C = Zn(CHO2)2·2H2O.
