SDS Volume (4675)
Volume 73. Metal and Ammonium Formate Systems, p None
Original Measurements
Eremeeva, I. L.; Kalacheva, V. G.; Schwartz, E. M.; Zh. Neorg. Khim. 22, 861-2 (1977).
Variables:
Room Temp: 10 °C
Prepared by:
St. Trendafilova, Chr. Balarew
Method/Apparatus/Procedure:
The isothermal method was used. Equilibrium was established when a constant pH, diffraction coefficient and concentration of $\ce{H3BO3}$ were reached. The $\ce{NH4^{+}}$, $\ce{Ca^{2+}}$ and $\ce{B^{3+}}$ contents were determined as $\ce{CaO}$ and $\ce{B2O3}$. The composition of the solid phases was determined by the Schreinemakers method.
Source and Purity of Materials:
- $\ce{Ca(CHO2)2}$ was prepared by reaction of $\ce{CaCO3}$ with C$\ce{H2O2}$. The product was recrystallized twice. Suprapure grade boric acid was used.
Estimated Errors:
Ambient temperature: ±0.02°C.
Components:
- Calcium formate, $\ce{ Ca(CHO2)2 }$; [544-17-2] NIST WebBook
- Boric acid, $\ce{ H3BO3 }$; [10043-35-3] NIST WebBook
- Water, $\ce{ H2O }$; [7732-18-5] NIST WebBook
Experimental Data
Solubility values in the Ca(CHO2)2-H3BO3-H2O system at 10°C.
| 100w1 | 100w2 | m1 (mol/kg) | m2 (mol/kg) | Phase (s) () |
|---|---|---|---|---|
| 14.06 | 0.0 | 1.26 | 0.0 | A |
| 13.91 | 2.44 | 1.28 | 0.47 | A |
| 13.84 | 3.01 | 1.28 | 0.59 | A |
| 13.87 | 3.27 | 1.29 | 0.64 | A |
| 13.87 | 3.16 | 1.28 | 0.62 | A |
| 13.74 | 3.89 | 1.28 | 0.76 | A |
| 13.72 | 4.30 | 1.29 | 0.85 | A |
| 13.70 | 4.79 | 1.29 | 0.95 | A + B |
| 10.44 | 4.50 | 0.94 | 0.86 | B |
| 6.02 | 4.30 | 0.52 | 0.78 | B |
| 4.21 | 3.99 | 0.35 | 0.70 | B |
| 3.22 | 3.81 | 0.27 | 0.66 | B |
| 1.08 | 3.67 | 0.09 | 0.62 | B |
| 0.0 | 3.52 | 0.0 | 0.52 | B |
(a) The molality values were calculated by the compilers.
(b) The solid phases are: A = Ca(CHO2)2; B = H3BO3.
