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NEET CHEMISTRYThermodynamicsMedium

Question

For irreversible expansion of an ideal gas under isothermal conditions, the correct option is:

A

ΔU=0,ΔStotal0\Delta U = 0, \Delta S_{total} \neq 0

B

ΔU0,ΔStotal=0\Delta U \neq 0, \Delta S_{total} = 0

C

ΔU=0,ΔStotal=0\Delta U = 0, \Delta S_{total} = 0

D

ΔU0,ΔStotal0\Delta U \neq 0, \Delta S_{total} \neq 0

Step-by-Step Solution

For an ideal gas, internal energy is a function of temperature only. Since the process is isothermal, the change in temperature is zero (ΔT=0\Delta T = 0), which implies the change in internal energy is also zero (ΔU=0\Delta U = 0) . For any irreversible process, the total entropy change of the universe (system + surroundings) must be strictly positive (ΔStotal>0\Delta S_{total} > 0), meaning ΔStotal0\Delta S_{total} \neq 0 .

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.

CHEMISTRYThermodynamicsirreversibleexpansionisothermalconditionscorrect

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