(b) In a particular spontaneous process the entropy of the system decreases. What can you conclude about the sign and magnitude of ΔS_surr?

Key Concepts

Entropy (S)

Entropy is a measure of the disorder or randomness in a system. In thermodynamics, it quantifies the number of ways a system can be arranged, with higher entropy indicating greater disorder. For spontaneous processes, the second law of thermodynamics states that the total entropy of an isolated system must increase over time, which is crucial for understanding the behavior of systems in nature.

Second Law of Thermodynamics

The second law of thermodynamics states that in any spontaneous process, the total entropy of the universe (system plus surroundings) must increase. This principle implies that if the entropy of a system decreases, the entropy of the surroundings must increase by a greater amount to ensure that the overall entropy change is positive, thus driving the spontaneity of the process.

Gibbs Free Energy (ΔG)

Gibbs free energy is a thermodynamic potential that measures the maximum reversible work obtainable from a system at constant temperature and pressure. It is defined as ΔG = ΔH - TΔS, where ΔH is the change in enthalpy, T is the temperature in Kelvin, and ΔS is the change in entropy. A negative ΔG indicates a spontaneous process, linking the concepts of entropy and energy changes in chemical reactions.