Other
Scientific paper
Oct 1994
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1994gecoa..58.4281r&link_type=abstract
Geochimica et Cosmochimica Acta, vol. 58, Issue 20, pp.4281-4291
Other
1
Scientific paper
New thermodynamic data are presented for mixing of calcite (CaCO 3 (s)) and otavite (CdCO 3 (s)) to form Ca x Cd 1-x CO 3 (s) solutions. A reversible equilibrium was achieved between the aqueous solution and the metastable solid solution using electrochemical double cells and a new electrode of the third kind. Evidence that the cell reactions are reversible includes demonstration of Nernstian response to changes in electrolyte composition and an absence of significant hysteresis in cell current-voltage and current-temperature (10-35°C) plots. We observe negative excess Gibbs energies for mixing on the order of 0 to -6.6 kJ · mol -1 ; these magnitudes are sensitive to uncertainties in the estimates of G o f [ CdCO 3 ( s )]. The double-cell method is potentially useful in other systems where, through incorporation of impurities, the activity of the CaCO 3 (s) is not unity relative to the standard state of the pure, well-crystallized, endmember mineral. It remains to be seen whether the double cell method is equally useful for systems, such as the Ca x Mg 1- x CO 3 ( s ) or Ca x Sr 1- x CO 3 ( s ) solid solutions, that have variable and positive excess Gibbs energies, but some of the same advantages would apply.
Casey William H.
McBeath Molly K.
Rock Peter A.
Walling Erin M.
No associations
LandOfFree
A new method for determining Gibbs energies of formation of metal-carbonate solid solutions: 1. The Ca x Cd 1-x CO 3 (s) system at 298 K and 1 bar does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with A new method for determining Gibbs energies of formation of metal-carbonate solid solutions: 1. The Ca x Cd 1-x CO 3 (s) system at 298 K and 1 bar, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A new method for determining Gibbs energies of formation of metal-carbonate solid solutions: 1. The Ca x Cd 1-x CO 3 (s) system at 298 K and 1 bar will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1070888