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<oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
  <dc:contributor>E. A. Jenne</dc:contributor>
  <dc:creator>D. Kirk Nordstrom</dc:creator>
  <dc:date>1977</dc:date>
  <dc:description>&lt;div id="preview-section-abstract"&gt;&lt;div id="abstracts" class="Abstracts u-font-serif text-s"&gt;&lt;div id="aep-abstract-id4" class="abstract author"&gt;&lt;div id="aep-abstract-sec-id5"&gt;&lt;p&gt;Calculation of chemical equilibria in 351 hot springs and surface waters from selected geothermal areas in the western United States indicate that the solubility of the mineral fluorite, CaF&lt;sub&gt;2&lt;/sub&gt;, provides an equilibrium control on dissolved fluoride activity. Waters that are undersaturated have undergone dilution by non-thermal waters as shown by decreased conductivity and temperature values, and only 2% of the samples are supersaturated by more than the expected error. Calculations also demonstrate that simultaneous chemical equilibria between the thermal waters and calcite as well as fluorite minerals exist under a variety of conditions.&lt;/p&gt;&lt;p&gt;Testing for fluorite solubility required a critical review of the thermodynamic data for fluorite. By applying multiple regression of a mathematical model to selected published data we have obtained revised estimates of the p&lt;i&gt;K&lt;/i&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;(10,96),&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;ΔG&lt;/i&gt;&lt;sup&gt;&lt;i&gt;o&lt;/i&gt;&lt;/sup&gt;&lt;sub&gt;&lt;i&gt;f&lt;/i&gt;&lt;/sub&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;(−280.08 kcal/mole),&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;ΔH&lt;/i&gt;&lt;sup&gt;&lt;i&gt;o&lt;/i&gt;&lt;/sup&gt;&lt;sub&gt;&lt;i&gt;f&lt;/i&gt;&lt;/sub&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;(−292.59 kcal/mole), S° (16.39 cal/deg/mole) and&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;C&lt;/i&gt;&lt;sup&gt;&lt;i&gt;o&lt;/i&gt;&lt;/sup&gt;&lt;sub&gt;&lt;i&gt;P&lt;/i&gt;&lt;/sub&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;(16.16 cal/deg/mole) for CaF&lt;sub&gt;2&lt;/sub&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;at 25°C and 1 atm. Association constants and reaction enthalpies for fluoride complexes with boron, calcium and iron are included in this review. The excellent agreement between the computer-based activity products and the revised p&lt;i&gt;K&lt;/i&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;suggests that the chemistry of geothermal waters may also be a guide to evaluating mineral solubility data where major discrepancies are evident.&lt;/p&gt;&lt;/div&gt;&lt;/div&gt;&lt;/div&gt;&lt;/div&gt;&lt;div id="preview-section-introduction"&gt;&lt;br&gt;&lt;/div&gt;&lt;div id="preview-section-snippets"&gt;&lt;br&gt;&lt;/div&gt;&lt;div id="preview-section-references"&gt;&lt;br&gt;&lt;/div&gt;</dc:description>
  <dc:format>application/pdf</dc:format>
  <dc:identifier>10.1016/0016-7037(77)90224-1</dc:identifier>
  <dc:language>en</dc:language>
  <dc:publisher>Elsevier</dc:publisher>
  <dc:title>Fluorite solubility equilibria in selected geothermal waters</dc:title>
  <dc:type>article</dc:type>
</oai_dc:dc>