What is Delta G in Thermodynamics?

Answer: In every chemical reaction, there is a change in the amount of free energy. This change is called delta G (G). Changes in free energy can be found in any mechanism that goes through a transition, like a chemical reaction. To figure out G, subtract the amount of energy lost to entropy (called S) from the total amount of energy change in the system. Gibbs on thermodynamics Free Energy (G) is the energy that can be used to do work that comes from chemical reactions. The free energy of a system is the sum of its enthalpy (H) and the product of its temperature (Kelvin) and entropy (S). This is also called “free reaction energy” (G).