Description
Return reaction free energy and standard equilibrium constant.
Biochemical amounts, ionization and free energies depend on units, standard states, activities and molecular composition. A supplied concentration ratio or independent-group formula is one local model relation rather than a complete equilibrium or verified molecular characterization.
Return reaction free energy and standard equilibrium constant.
When to use this tool
Use Reaction Equilibrium Free Energy Term when checking the stated biochemical amount, charge, equilibrium or material-basis convention.
How to use the tool and how it works
- Enter standardFreeEnergy, gasConstant, temperatureK, reactionQuotient. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read freeEnergy, equilibriumConstant. Use the output convention below.
Return reaction free energy and standard equilibrium constant. Require R, temperatureK and dimensionless reactionQuotient > 0; freeEnergy = standardFreeEnergy+R*T*ln(Q), K = exp(-standardFreeEnergy/(R*T)).1
Reaction free energy, equilibrium constants and redox potentials depend on consistent reaction and standard-state conventions. A local formula does not determine an actual equilibrium composition.2
| Input field | Meaning and units | Accepted input |
|---|---|---|
| standardFreeEnergy | Molar standard reaction free energy, compatible with gasConstant*temperatureK. | Required. Finite number. |
| gasConstant | Gas Constant | Required. Finite number; strictly above 0. |
| temperatureK | Temperature K | Required. Finite number; strictly above 0. |
| reactionQuotient | Positive dimensionless activity quotient on the stated standard-state convention. | Required. Finite number; strictly above 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| freeEnergy | Free Energy | Required. Finite number. |
| equilibriumConstant | Equilibrium Constant | Required. Finite number. |
{
"input": {
"standardFreeEnergy": 0,
"gasConstant": 8,
"temperatureK": 300,
"reactionQuotient": 2
},
"output": {
"freeEnergy": 1663.5532333438687,
"equilibriumConstant": 1
}
}Limitations and assumptions
- Standard-state, activity and per-mole energy conventions must match; no equilibrium composition, pH transformation or actual reaction direction is verified.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Use compatible standard states, verified chemical identity and an appropriate complete activity/speciation or measurement model for physical interpretation.
References
Similar or alternative tools
- Biochemical Standard State Concentration Factor
Return a dimensionless standard-state concentration proxy and power.
- Biochemical Redox Electron Count Factor
Return molar redox free-energy change and charge.