Extraction constant

{
  "id": "MLC-T-CHM-004289",
  "term": "Extraction constant",
  "field": "Chemistry",
  "definition": "The equilibrium constant of the overall extraction reaction, for example a metal ion in water reacting with an organic-phase reagent HL to give an organic-soluble complex and hydrogen ions. In its thermodynamic form it is written with activities at zero ionic strength, and it is related to the distribution ratios of the complex and the reagent, the overall formation constant of the complex and the acid dissociation constant of the reagent. A distribution constant, in contrast, describes a single species passing between phases.",
  "synonyms": [
    "extraction equilibrium constant"
  ],
  "subject": "Analytical Chemistry",
  "see_also": [
    "crown",
    "cryptand",
    "dissociation",
    "equilibrium constant",
    "extraction",
    "formation constant",
    "ionic strength",
    "partition constant",
    "polymerization",
    "solvation"
  ],
  "references": [
    "Orange Book, 2nd ed., p. 89 (https://media.iupac.org/publications/analytical_compendium/)",
    "PAC, 1993, 65, 2373. 'Nomenclature for liquid-liquid distribution (solvent extraction) (IUPAC Recommendations 1993)' on page 2383 (https://doi.org/10.1351/pac199365112373)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/extraction-constant/"
}