Calculate the Gibbs free energy change (ΔG), equilibrium constant (K), and van’t Hoff parameters for a chemical reaction from enthalpy and entropy data. Use this tool to predict whether a reaction is spontaneous at a given temperature, to relate thermodynamics to equilibrium position, or to understand how temperature shifts the equilibrium via the van’t Hoff equation. A negative ΔG indicates a spontaneous reaction under the given conditions, while the equilibrium constant tells you whether products or reactants are favored at equilibrium.

About Gibbs Free Energy

Gibbs free energy (G = H − TS) determines whether a chemical reaction is spontaneous under constant temperature and pressure. The relationship ΔG° = −RT ln K connects thermodynamics to equilibrium, and the van’t Hoff equation describes how equilibrium constants change with temperature — essential for understanding reaction feasibility, biochemical energy transduction, and industrial process design.