Adsorption, coagulation, flocculation, and entropy

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Adsorption, coagulation, and flocculation are critical methods for separating substances from mixtures, often leading to a decrease in entropy. This observation raises questions about the applicability of the second law of thermodynamics, which states that total entropy should not decrease in an isolated system. The discussion suggests that while local decreases in entropy can occur during these processes, the overall system entropy must be considered. The relationship between enthalpy change and entropy is highlighted, emphasizing the importance of analyzing the entire system. Ultimately, these processes illustrate the complexity of thermodynamic principles in real-world applications.
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Homework Statement


Adsorption, coagulation, and flocculation are all important processes to remove or separate target substances from mixtures. In these processes, we can observe the spontaneous decrease of entropy.; can we therefore conclude that the second law of thermodynamics doesn't always apply. Comment on this contradiction.

Homework Equations


Hint: dH - TdST <= 0
 
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Think about the whole system entropy.
 

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