What thermodynamic behavior characterizes any chemical reaction involving condensed phases at absolute zero temperature?
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Answer: C. Δ S° = 0 , Δ E° = 0
Explanation
The Third Law of Thermodynamics states that the entropy of a pure crystalline substance approaches zero at absolute zero. Nernst heat theorem indicates that entropy changes for reactions involving condensed phases vanish at zero Kelvin. Internal energy changes or related energy derivatives also approach zero as thermal motion ceases entirely at absolute zero. Absolute zero represents the theoretical lowest temperature limit where molecular thermal motion reaches minimum energy states. Thermodynamic calculations require absolute entropy values made possible by applying the Third Law of Thermodynamics. Condensed phases include solid and liquid states where molecular interactions differ significantly from gaseous behavior.
Option A incorrectly assumes Gibbs free energy and enthalpy changes universally vanish for all reactions at zero Kelvin. Option B misses the specific energy derivative conditions defined by the Nernst heat theorem at absolute zero. Option D specifies heat capacity derivatives which do not capture the exact thermodynamic criteria stated by the theorem.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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