Gibbs free energy, denoted G, combines enthalpy and entropy into a single value. The change in free energy, ΔG, is equal to the sum of the enthalpy plus the product of the temperature and entropy of the system. ΔG can predict the direction of the chemical reaction under two conditions: constant temperature and constant pressure.

In thermodynamics, the Gibbs free energy (or Gibbs energy as the recommended name; symbol ) is a thermodynamic potential that can be used to calculate the maximum amount of work, other than pressure–volume work, that may be performed by a thermodynamically closed system at constant temperature and pressure.

Free energy functions are Legendre transforms of the internal energy. The Gibbs free energy is given by G = H − TS, where H is the enthalpy, T is the absolute temperature, and S is the entropy. H = U + pV, where U is the internal energy, p is the pressure, and V is the volume.

Free energy is used to determine how systems change and how much work they can produce. It is expressed in two forms: the Helmholtz free energy F, sometimes called the work function, and the Gibbs free energy G.

2023年9月28日 · This form of the equation provides a useful link between these two essential thermodynamic properties, and it can be used to derive equilibrium constants from standard free energy changes and vice versa.

Gibbs free energy, also known as the Gibbs function, Gibbs energy, or free enthalpy, is a quantity that is used to measure the maximum amount of work done in a thermodynamic system when the temperature and pressure are kept constant.

Gibbs free energy is an important value in thermodynamics that allows you to predict aspects of a chemical reaction. In this tutorial, we will learn why the Gibbs free energy equation is important and how to solve problems in which it is involved. We will also define what a spontaneous reaction is. What is specific heat?

This page introduces Gibbs free energy (often just called free energy), and shows how it can be used to predict the feasibility of reactions. If you have already read the page about how to do this with total entropy changes, you will find a little bit of repetition on this page. That's all …

2025年1月6日 · Calculate Gibbs free energy easily with a simple formula guide, covering thermodynamic principles, energy equations, and spontaneous reactions, using delta G, entropy, and enthalpy values to determine reaction feasibility and chemical equilibrium.

2025年2月18日 · Calculate Gibbs free energy with ease, understanding thermodynamic principles, spontaneity, and equilibrium constants, using formulas and equations for precise energy change predictions in chemical reactions.