Solubility of natural fluorite at 25°C

D. W. Brown; C. E. Roberson

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USGS · 70156489

Solubility of natural fluorite at 25°C

D. W. Brown·C. E. Roberson

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Abstract

The solubility products of two samples of natural fluorite from Rosiclare, Ill., and from Madoc, Ontario, were determined at 25°C by analyses of calcium and fluoride in sodium perchlorate solutions of varying ionic strength over a period of 3 years. Calcium concentrations were analyzed by atomic absorption spectrophotometry, fluoride concentrations were measured colorimetrically, and fluoride activities were measured using a specific ion electrode. The solubility products at the end of 3 years were determined by extrapolation to zero ionic strength. The final solubility product was found to be 10 -10.58±0.17 .

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D. W. Brown, C. E. Roberson. 1977. Solubility of natural fluorite at 25°C. https://pubs.usgs.gov/publication/70156489

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