The principle stating that the entropy of a completely pure crystalline substance vanishes at absolute zero is derived from which thermodynamic law__________________?
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Answer: A. Third law of thermodynamics
Explanation
The third law of thermodynamics states that pure crystalline entropy approaches zero at absolute zero. Perfect crystals have a single microstate arrangement at absolute zero, eliminating thermal disorder. Max Planck formulated this specific thermodynamic law to calculate absolute entropy values easily. Entropy measures the microscopic disorder and thermal energy distribution within a thermodynamic system. Absolute zero represents the theoretical temperature where all thermal molecular motion ceases completely. Real crystals may retain minor defects, but ideal lattices follow this third law principle.
Chemists use third law entropy tables to calculate spontaneity of industrial chemical reactions. Cryogenic research relies on absolute entropy values to study low temperature phase transitions. Understanding entropy baselines is essential for evaluating overall thermodynamic efficiency limits. The second law governs entropy increases and heat engine efficiency limits rather than absolute zero bounds. The Nernst heat theorem provided the mathematical foundation that led to the third law. Maxwell relations link thermodynamic variables together rather than defining absolute entropy limits.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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