Compilation - Cobalt formate with Water (IUPAC SDS Volume 73)
SDS Volume (4773)
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: 10 - 80 °C
Prepared by:
St. Trendafilova, Chr. Balarew
Method/Apparatus/Procedure:
The decrease of supersaturation was studied isothermally in about a 2% excess of formic acid to suppress hydrolysis of the salt. Equilibrium was reached in 15-20 h. The cobalt concentration was determined using Complexone III at pH 5.5-6 with Xylenol orange as indicator. The composition of the solid phase was determined by X-ray diffraction and chemical analysis.
Source and Purity of Materials:
- Cobalt formate was prepared by neutralizing basic cobalt carbonate with dilute formic acid.
Components:
- Cobalt formate, $\ce{ Co(CHO2)2 }$; [544-18-3] NIST WebBook
- Water, $\ce{ H2O }$; [7732-18-5] NIST WebBook
Experimental Data
Solubility polytherm of the Co(CHO2)2-H2O system.
| $T$ (°C) | 100w1 | m1 (mol/kg) | Phase (s) () |
|---|---|---|---|
| 10 | 2.03 | 0.139 | A |
| 15 | 2.18 | 0.150 | A |
| 20 | 2.34 | 0.161 | A |
| 25 | 2.44 | 0.168 | A |
| 30 | 2.55 | 0.176 | A |
| 35 | 2.69 | 0.186 | A |
| 40 | 2.85 | 0.197 | A |
| 45 | 3.05 | 0.211 | A |
| 50 | 3.33 | 0.231 | A |
| 55 | 3.41 | 0.237 | A |
| 60 | 3.59 | 0.250 | A |
| 65 | 3.79 | 0.264 | A |
| 70 | 4.02 | 0.281 | A |
| 75 | 4.19 | 0.294 | A |
| 80 | 4.28 | 0.300 | A |
(a) These values were calculated by the compilers.
(b) The solid phase is: A = Co(CHO2)2ยท2H2O.
