To derive the integrated Clausius-Clapeyron formula, ln (P2/P1) = (ΔHV/R) (1/T1 – 1/T2), from the exact Clapeyron equation, what assumptions are made regarding the____________________?
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Answer: D. All A , B. & C.
Explanation
Integrated Clausius Clapeyron equation relies on assuming ideal gas behavior for vapor phases. Derivation assumes liquid molar volume is negligible compared to vapor volume at low pressures. Heat of vaporization is assumed constant and independent of temperature changes across the interval. Clapeyron equation is exact for any phase transition but requires simplifying assumptions for integration. Ideal gas law provides a simple mathematical expression for vapor molar volume calculations. Integration transforms differential pressure temperature slopes into a manageable logarithmic formula.
Chemical engineers use the integrated Clausius Clapeyron equation to estimate vapor pressures rapidly. Boiling point elevations and vapor pressure curves are modeled effectively using these approximations. Understanding underlying assumptions prevents applying the integrated formula beyond its valid pressure range. Selecting only vapor phase ideality ignores the necessary assumptions regarding liquid volume and vaporization heat. Focusing solely on heat of vaporization misses the critical liquid volume simplification step. Checking all options correctly identifies that all three stated assumptions are mathematically required.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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