What does delta G equal according to thermodynamic principles?

Delta G, which represents the change in Gibbs free energy, is fundamentally related to the enthalpy change (Delta H) and the entropy change (Delta S) of a system. According to thermodynamic principles, the correct relationship is expressed by the equation:

Delta G = Delta H - T(Delta S)

In this equation, Delta H indicates the change in enthalpy, which reflects the heat content of the system, while T represents the absolute temperature in Kelvin. The term T(Delta S) accounts for the temperature-dependent contribution of entropy change to the free energy of the system.

This equation allows us to determine whether a reaction will occur spontaneously. A negative Delta G suggests that a process can occur spontaneously at constant temperature and pressure, while a positive Delta G indicates that the reaction is non-spontaneous in that direction.

Understanding this relationship is crucial in various scientific fields, including chemistry and biochemistry, as it provides insight into the energy dynamics of chemical reactions and physical processes.