| Autor: |
G. Meinrath, Hideyo Takeishi |
| Rok vydání: |
1993 |
| Předmět: |
|
| Zdroj: |
Journal of Alloys and Compounds. 194:93-99 |
| ISSN: |
0925-8388 |
| DOI: |
10.1016/0925-8388(93)90651-3 |
| Popis: |
A redetermination of the solubility products of NdOHCO 3 (s) and Nd 2 (CO 3 ) 3 ·(4.5–6)H 2 O(s) in 0.1 M NaClO 4 is presented, extending existing data to a wider variety of CO 2 partial pressures and a wider concentration range. NdOHCO 3 (s) is found in equilibrium with 0.03% and 0.3% CO 2 partial pressures; Nd 2 (CO 3 ) 3 ·(4.5–6)H 2 O(s) is found in equilibrium with 1.0%, 8.0% and 100% CO 2 partial pressures. The solubility products log K sp (NdOHCO 3 ) = −20.12 ± 0.09 and log K sp (Nd 2 (CO 3 3 ·(4.5–6)H 2 O) = −31.54 ± 0.11 have been determined. Evidence is presented that Nd 2 (CO 3 ) 3 ·(4.5–6)H 2 O(s) is probably only metastable in equilibrium with 1.0% CO 2 partial pressure. Gibbs free energies of formation have been calculated as ΔG f o ((Nd2(CO 3 ) 3 (s)) = − 3115.9 ± 4.0 kJ mol −1 and ΔG f o (NdOHCO 3 (s)) = −14.76.0±2.9 kJ mol −1 . |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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