Reaction quotient and equilibrium constant
For a balanced reaction with signed stoichiometric coefficients νᵢ, the reaction quotient is the product of activities raised to those coefficients.
Key knowledge
For a balanced reaction with signed stoichiometric coefficients νᵢ, the reaction quotient is the product of activities raised to those coefficients. At equilibrium Q equals the dimensionless equilibrium constant K for the specified temperature and standard states.
Values and equations
Q = ∏ᵢ aᵢ^νᵢ; Qeq = K
- Q
- reaction quotient 1
- aᵢ
- activity of species i 1
- νᵢ
- signed stoichiometric coefficient 1
- K
- equilibrium constant 1
Conditions and scope
- Products have positive νᵢ and reactants negative νᵢ; activities and standard states must be consistent.
- Pure condensed phases have unit activity in their stated standard states; concentration and pressure substitutions require an appropriate ideal approximation.
Sources · 1
References
Sources retain their recorded scope. A source link alone does not establish verification of every statement.
Evidence and review
Inspected mass-action quotient, heterogeneous equilibrium and explicit dimensionless-standard-state qualification.
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Entry details
Permanent link to this entry ↗- Record identity
- uni-chem-reaction-quotient
- Revision
- core.1
- Structured reference record
- University core expansion