Halochromism

{
  "id": "MLC-T-CHM-005080",
  "term": "Halochromism",
  "field": "Chemistry",
  "definition": "The phenomenon where a substance changes color upon a change in pH, specifically when interacting with an acid or a base. This color alteration results from a reversible structural change in the molecule, often involving protonation or deprotonation, which affects its electronic absorption spectrum. Indicators like litmus paper exhibit halochromism.",
  "subject": "Organic and Biomolecular Chemistry",
  "see_also": [
    "acid",
    "base",
    "chemical reaction",
    "salt"
  ],
  "references": [
    "PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1119 (https://doi.org/10.1351/pac199466051077)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/halochromism/"
}