Standard subtraction method

{
  "id": "MLC-T-CHM-011307",
  "term": "Standard subtraction method",
  "field": "Chemistry",
  "definition": "An electroanalytical calibration approach related to standard addition, in which a known amount of a reagent that reacts stoichiometrically with the analyte ion, such as a complexing or precipitating agent, is added to the sample. The shift in electrode potential this causes is used to work out the initial activity or concentration of the ion. Unlike standard addition, the added reagent lowers the free analyte level instead of raising it.",
  "subject": "Analytical Chemistry",
  "references": [
    "Orange Book, 2nd ed., p. 171 (https://media.iupac.org/publications/analytical_compendium/)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/standard-subtraction-method/"
}