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NEET CHEMISTRYThermodynamicsEasy

Question

Joule-Thomson expansion is [JIPMER 2000]:

A

Isobaric

B

Isoenthalpic

C

Isothermal

D

None of these

Step-by-Step Solution

Joule-Thomson expansion (also known as the throttling process) involves the expansion of a gas from a high-pressure region to a low-pressure region through a porous plug or restricted valve under adiabatic conditions (q=0q = 0) . According to the first law of thermodynamics, for such a process, the enthalpy (H=U+pVH = U + pV) remains constant from the initial to the final state . Therefore, the process is described as isoenthalpic. While the sources provided discuss Joule's experimental work on internal energy and the definition of enthalpy as a state function, the specific classification of the Joule-Thomson expansion as isoenthalpic is a standard principle in chemical thermodynamics .

Exam Context & Concepts Covered

This question aligns with the NEET CHEMISTRY syllabus, specifically targeting concepts from Thermodynamics. Mastering this topic is crucial for scoring well in the upcoming medical entrance examinations. Solving conceptually related problems will help you understand the nuances of these concepts and improve your problem-solving speed.

CHEMISTRYThermodynamicsjoulethomsonexpansionjipmer

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