Enthalpy of activation

{
  "id": "MLC-T-CHM-003955",
  "term": "Enthalpy of activation",
  "field": "Chemistry",
  "definition": "The change in enthalpy that occurs when reactants form the transition state in a chemical reaction. It represents the energy barrier that must be overcome for the reaction to proceed, specifically considering the heat exchange at constant pressure. This thermodynamic parameter is derived from the temperature dependence of the rate constant using the Eyring equation.",
  "subject": "Physical and Biophysical Chemistry",
  "see_also": [
    "Boltzmann constant",
    "Planck constant",
    "activation",
    "activation energy",
    "enthalpy",
    "entropy of activation",
    "gas constant",
    "molecularity",
    "standard concentration",
    "transition state theory"
  ],
  "references": [
    "Green Book, 2nd ed., p. 56 (https://goldbook.iupac.org/files/pdf/green_book_2ed.pdf)",
    "PAC, 1993, 65, 2291. 'Nomenclature of kinetic methods of analysis (IUPAC Recommendations 1993)' on page 2294 (https://doi.org/10.1351/pac199365102291)",
    "PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1113 (https://doi.org/10.1351/pac199466051077)",
    "PAC, 1996, 68, 149. 'A glossary of terms used in chemical kinetics, including reaction dynamics (IUPAC Recommendations 1996)' on page 164 (https://doi.org/10.1351/pac199668010149)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/enthalpy-of-activation/"
}