Which of the following mathematical inequalities can serve as a definitive and complete criterion fo — Thermodynamics and Thermochemistry Chemistry Question

💡 Solution & Explanation

The Second Law directly dictates a spontaneous process strictly increases the total entropy of the universe: $\Delta S_{universe} > 0$, which is fundamentally equivalent to $\Delta S_{sys} + \Delta S_{surr} > 0$. At constant temperature and pressure, this translates exactly to the Gibbs free energy criterion: $\Delta G_{sys} < 0$. However, $\Delta H < 0$ alone is insufficient; an exothermic process can be entirely non-spontaneous if $T\Delta S$ is heavily negative.