Components:
(1) Strontium formate,
Sr(CHO2)2; [592-89-2]
NIST WebBook
(2) Copper formate,
Cu(CHO2)2; [544-19-4]
NIST WebBook
(3) Water,
H2O; [7732-18-5]
NIST WebBook
Original Measurements
Portnova, S. M.; Krassilov, Yu. I.; Kuznetzov, N. T.; Balakaeva, I. V.; Zh. Neorg. Khim. 35, 237-41 (1990).
Variables:
Ambient temperature: Composition at 25 °C
Prepared by:
St. Trendafilova, Chr. Balarew
Method/Apparatus/Procedure:
The isothermal method was used. Four weeks were allowed for equilibration. The Cu2+ content was determined complexometrically. The Ba2+ content was determined gravimetrically as BaSO4 after the Cu2+ was bound with Complexon III. The composition of the solid phases was determined by the Schreinemakers' method, by DT analysis and by x-ray fluorescence spectroscopy.
Source and Purity of Materials:
- The formates were obtained by neutralizing dilute formic acid with p.a. grade copper or barium oxides.
Estimated Errors:
Ambient temperature: Not given.
Experimental Values:
Solubility values in the Ba(CHO2)2-Cu(CHO2)2-H2O system at 25°C.
| 100w1 | 100w2 | m1 (mol/kg)a | m2 (mol/kg)a | Phase (s)b |
|---|---|---|---|---|
| - | 9.46 | - | 6.80 x 10-1 | A |
| 5.79 | 8.94 | 2.99 x 10-1 | 6.83 x 10-1 | A |
| 10.78 | 9.96 | 5.98 x 10-1 | 8.18 x 10-1 | A |
| 13.26 | 11.3 | 7.73 x 10-1 | 9.75 x 10-1 | A |
| 13.44 | 10.81 | 7.80 x 10-1 | 9.29 x 10-1 | A + B |
| 13.28 | 10.76 | 7.69 x 10-1 | 9.22 x 10-1 | B |
| 12.99 | 10.05 | 7.42 x 10-1 | 8.50 x 10-1 | B |
| 15.05 | 8.46 | 8.65 x 10-1 | 7.20 x 10-1 | B |
| 14.68 | 4.39 | 7.98 x 10-1 | 3.53 x 10-1 | B |
| 15.36 | 3.14 | 8.29 x 10-1 | 2.51 x 10-1 | B |
| 19.43 | 1.05 | 1.074 | 8.6 x 10-2 | B |
| 24.22 | 5.2 x 10-1 | 1.415 | 4.5 x 10-2 | B + C |
| 24.2 | 3.1 x 10-1 | 1.41 | 2.7 x 10-2 | C |
| 26.83 | - | 1.612 | - | C |
(a) The molality values were calculated by the compilers. (b) The solid phases are: A = Cu(CHO2)2·4H2O; B = Ba2Cu(CHO2)6·4H2O; C = Ba(CHO2)2.
