what is the second law of thermodynamics and how does it relate to entropy

The second law of thermodynamics states that the total entropy of a system either increases or remains constant in any spontaneous process, and it never decreases. References to this, 2. Entropy is a measure of disorder or randomness, and it is a thermodynamic property of all substances that is proportional to their degree of disorder. The greater the number of possible microstates for a system, the greater the disorder and the higher the entropy2. The second law of thermodynamics is related to entropy because it states that if the physical process is irreversible, the entropy of the system and the environment must increase, and the final entropy must be greater than the initial entropy. In other words, the second law of thermodynamics implies that the entropy of the universe tends to a maximum. As entropy increases, disorder increases, and energy disperses, causing systems to dissolve into chaos. Therefore, the second law of thermodynamics and entropy are closely related concepts that describe the tendency of the universe towards disorder and randomness.

References :

https://openstax.org/books/physics/pages/12-3-second-law-of-thermodynamics-entropy

https://www.britannica.com/science/entropy-physics

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