FormuLab
Chemistry

Standard Gibbs Energy and Equilibrium

Connect a reaction’s standard Gibbs energy change with its equilibrium constant.

Study tools
Save, share, export, or report this formula.
Source & review

Difficulty

Intermediate

Read time

3 min

Prerequisites

Algebra, logarithms, and molar quantities

Review statusNeeds review

Source

OpenStax, Chemistry 2e, §16.4

Adapted from Teng-Jui Lin’s CHEM 145 equation sheet. The linked textbook reference was used to check the equation and its physical context. Pending editorial review.

Adapted from Teng-Jui Lin, Equation Sheets, under CC BY 4.0.

FormuLab adapted notation and chemical symbols, added variable meanings, units, applicability conditions, and an original worked example.

Definition
Understanding the core concept

The standard reaction Gibbs energy determines the equilibrium constant at the stated temperature. A dimensionless K greater than one corresponds to a negative standard Gibbs energy change for the reaction as written.

Variables & Units
Understanding each component
SymbolMeaningUnits
Standard reaction Gibbs energy change
Molar gas constant
Absolute temperature
Dimensionless thermodynamic equilibrium constant
Real-World Applications
Where this formula is used in practice

Equilibrium prediction

Relate standard reaction energy to an equilibrium constant.

Standard reaction data

Convert a measured equilibrium constant into standard Gibbs energy.

Worked Example
Step-by-step calculation with real numbers

Problem

At 298.15 K a reaction has dimensionless equilibrium constant K = 10.0. Find its standard reaction Gibbs energy change.

Given

Solution

1
2
3

Final Answer

FormuLab is a study reference. Verify formulas, units, assumptions, and course-specific conventions before relying on them.

Browse by category

See all
EngineeringPhysicsChemistryMathematicsFluid MechanicsElectrical