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

Other

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

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.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

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.

Rate now

     

Profile ID: LFWR-SCP-O-1070888

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.