Activities and chemical potentials
Activity expresses composition relative to a specified thermodynamic standard state.
Key knowledge
Chemical activity relates a species' chemical potential to its standard-state value through μ = μ° + RT ln a. The activity is dimensionless; standard states and composition scales must be specified. Activity coefficients describe departures from the chosen ideal behaviour.
Conditions and scope
- The species, phase, temperature and standard-state convention must agree.
- Concentration or molality alone is not generally the activity.
Sources · 1
References
Sources retain their recorded scope. A source link alone does not establish verification of every statement.
Evidence and review
IUPAC Green Book section 2.11 standard-state and chemical-potential relations.
2026-10-10 · Checked dimensionless activity and compatible standard-state scope.
Entry details
Permanent link to this entry ↗- Record identity
- chem-activities-chemical-potential
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- university-reference.1
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- University reference