SOLID-SOLUTE PHASE-EQUILIBRIA IN AQUEOUS-SOLUTIONS .9. THERMODYNAMIC ANALYSIS OF SOLUBILITY MEASUREMENTS - LA(OH)(M)(CO3)(Q)CENTER-DOT-RH(2)O

Authors
GAMSJAGER H MARHOLD H KONIGSBERGER E TSAI YJ KOLMER H
Citation
H. Gamsjager et al., SOLID-SOLUTE PHASE-EQUILIBRIA IN AQUEOUS-SOLUTIONS .9. THERMODYNAMIC ANALYSIS OF SOLUBILITY MEASUREMENTS - LA(OH)(M)(CO3)(Q)CENTER-DOT-RH(2)O, Zeitschrift fur Naturforschung. A, A journal of physical sciences, 50(1), 1995, pp. 59-64
Citations number
17
Categorie Soggetti
Chemistry Physical",Physics
Journal title
Zeitschrift fur Naturforschung. A, A journal of physical sciences → ACNP
ISSN journal
09320784
Volume
50
Issue
1
Year of publication
1995
Pages
59 - 64
Database
ISI
SICI code
0932-0784(1995)50:1<59:SPIA.T>2.0.ZU;2-M
Abstract
The aqueous solubilities of La(OH)0.8(CO3)(1.1).0.1H(2)O, basic lantha num carbonate of ancylite type, have been investigated as a function o f ionic strength at 25.0 degrees C. The stoichiometric solubility cons tants defined by logK-ps0(I) = log[La3+] + 1.1 log p(CO2) - 3 log[H+] have the values 11.10, 11.32, 11.42, 11.63, and 11.70 for I = 0.1, 0. 25, 1.0, 2.0, and 4.0 mol kg(-1) (Na)ClO4 respectively. The extrapolat ion to infinite dilution using the Pitzer equations resulted in a ''th ermodynamic'' solubility constant, logK-pz0(0) = 10.48 +/- 0.08. This in turn led to the Gibbs energy of ancylite formation: elta(f)G(298)( Theta){La(OH)0.8(CO3)(1.1).0.1H(2)O} = - 1.531.5 kJ mol(-1).