Gas-phase acidity

Term · Chemistry · MLC-T-CHM-004767

A measure of how readily a molecule gives up a proton in the absence of solvent, expressed as the standard Gibbs energy change of the gas-phase reaction AH to A- plus H+. The enthalpy change of the same reaction is the deprotonation enthalpy, a related but separate quantity that leaves out the entropy term. Values typically exceed 1000 kJ/mol, because separating charges without solvation is costly.

Table 1. Record
Identifier	MLC-T-CHM-004767
Field	Chemistry
Subject	Organic and Biomolecular Chemistry
References	PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1116 (https://doi.org/10.1351/pac199466051077)

Record as JSON

{
  "id": "MLC-T-CHM-004767",
  "term": "Gas-phase acidity",
  "field": "Chemistry",
  "definition": "A measure of how readily a molecule gives up a proton in the absence of solvent, expressed as the standard Gibbs energy change of the gas-phase reaction AH to A- plus H+. The enthalpy change of the same reaction is the deprotonation enthalpy, a related but separate quantity that leaves out the entropy term. Values typically exceed 1000 kJ/mol, because separating charges without solvation is costly.",
  "subject": "Organic and Biomolecular Chemistry",
  "references": [
    "PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1116 (https://doi.org/10.1351/pac199466051077)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/gas-phase-acidity/"
}

Record 5,047 of 13,676 in Chemistry terminology (MLC-0109). Request the full dataset.