The thermodynamic identity Tds = dE – PdV is valid for___________________?
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Answer: D. Both B. and C
Explanation
The fundamental thermodynamic property relation remains universally applicable for analyzing fluid systems undergoing various physical changes. Open systems experience mass transfer alongside energy exchange requiring expanded mathematical formulations to account for compositional variations accurately. Single phase fluids maintain uniform physical properties throughout their volume making differential energy balance equations mathematically tractable. Thermodynamic identities combine the first and second laws to relate internal energy entropy pressure volume and temperature variables. Open systems allow both matter and energy to cross system boundaries unlike closed systems where mass remains strictly constant. Intensive and extensive properties define the macroscopic state of fluid mixtures in chemical engineering thermodynamics and process design.
Option A restricts applicability unnecessarily by ignoring closed systems which also satisfy the fundamental thermodynamic property relations. Option B excludes open systems which can be analyzed using these relations when compositional terms are properly included. Options failing to recognize dual applicability overlook the comprehensive nature of foundational thermodynamic conservation laws in fluid mechanics.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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