SDS Volume (4819)
Volume 73. Metal and Ammonium Formate Systems, p None
Original Measurements
Portnova, S. M.; Ahmatova, Zh. T.; Lepeshkov, I. N.; Zh. Neorg. Khim. 31, 2143-5 (1986).
Variables:
Room Temp: Composition at 25 °C
Prepared by:
St. Trendafilova, St. Tepavitcharova
Method/Apparatus/Procedure:
The isothermal method was used. Four weeks were allowed for equilibration. The strontium content of both phases was determined complexometrically in a basic medium, using methylthymolblue as indicator. The potassium content was determined by the tetraphenylborate method [1]. The composition of the solid phases was determined by the Schreinemakers' method.
Source and Purity of Materials:
- Suprapure grade $\ce{Sr(CHO2)2.2H2O}$ was recrystallized. $\ce{KCHO2}$ was prepared by the reaction of $\ce{KOH}$ with $\ce{H2CO2}$.
Estimated Errors:
Ambient temperature: No information is given.
Mass concentration (m/v) (1): No information is given.
References
1 Rusakova, G. G.; Zh. Anal. Khim. 18, 154 (1963).
Components:
- Potassium formate, $\ce{ KCHO2 }$; [590-29-4] NIST WebBook
- Strontium formate, $\ce{ Sr(CHO2)2 }$; [592-89-2] NIST WebBook
- Water, $\ce{ H2O }$; [7732-18-5] NIST WebBook
Experimental Data
Solubility values in the KCHO2-Sr(CHO2)2-H2O system at 25°C.
| 100w2 | 100w1 | m2 (mol/kg) | m1 (mol/kg) | Phase (s) () |
|---|---|---|---|---|
| 10.91 | - | 0.69 | - | A |
| 7.47 | 3.42 | 0.47 | 0.46 | A |
| 6.08 | 9.23 | 0.40 | 1.30 | A |
| 4.19 | 11.94 | 0.28 | 1.69 | A |
| 2.91 | 18.60 | 0.21 | 2.82 | A |
| 1.80 | 25.70 | 0.14 | 4.21 | A |
| 1.26 | 39.74 | 0.12 | 8.01 | A |
| 1.46 | 40.35 | 0.14 | 8.24 | A |
| 1.35 | 45.23 | 0.14 | 10.07 | A |
| 1.62 | 46.30 | 0.18 | 10.57 | A |
| 1.21 | 47.30 | 0.13 | 10.92 | A |
| 1.76 | 49.34 | 0.20 | 11.99 | A |
| 1.51 | 50.14 | 0.18 | 12.33 | A |
| 1.70 | 56.10 | 0.23 | 15.80 | A |
| 1.61 | 56.93 | 0.22 | 16.32 | A |
| 2.18 | 59.63 | 0.32 | 18.56 | A |
| 2.62 | 61.73 | 0.41 | 20.58 | A |
| 3.03 | 58.81 | 0.45 | 18.32 | A |
| 3.50 | 63.15 | 0.59 | 22.51 | A |
| 3.71 | 61.22 | 0.60 | 20.75 | A |
| 3.91 | 64.28 | 0.69 | 24.02 | A |
| 4.00 | 64.44 | 0.71 | 24.27 | A |
| 6.11 | 70.01 | 1.44 | 34.85 | A |
| 6.13 | 71.79 | 1.56 | 38.65 | A + B |
| 6.01 | 71.22 | 1.49 | 37.18 | B |
| 2.23 | 73.39 | 0.49 | 35.64 | B |
| 1.27 | 79.13 | 0.36 | 47.99 | B |
| 0.71 | 81.67 | 0.23 | 55.10 | B |
| - | 81.82 | - | 53.50 | B |
(a) The solid phases are: A = Sr(CHO2)2ยท2H2O; B = KCHO2.
(b) The molality values were calculated by the compilers.
