Residual liquid junction error

{
  "id": "MLC-T-CHM-010225",
  "term": "Residual liquid junction error",
  "field": "Chemistry",
  "definition": "The error in a potentiometric measurement, such as pH, caused by the assumption that the liquid junction potential stays constant when the test solution replaces the calibration standard in the operational cell. In reality the junction potential depends on the composition of the solutions on either side, so its value changes slightly between the two, and that change is left uncorrected. Matching the ionic strength and composition of sample and standard reduces it.",
  "synonyms": [
    "residual liquid junction potential error"
  ],
  "subject": "Physical and Biophysical Chemistry",
  "see_also": [
    "liquid junction"
  ],
  "references": [
    "PAC, 1985, 57, 531. 'Definition of pH scales, standard reference values, measurement of pH and related terminology (Recommendations 1984)' on page 541 (https://doi.org/10.1351/pac198557030531)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/residual-liquid-junction-error/"
}