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NEET CHEMISTRYThermodynamicsEasy

Question

A system is changed from state A to state B by one path and from B to A by another path. If E1E_{1} and E2E_{2} are the corresponding changes in internal energy, then [Pb. PMT 2001]:

A

E1+E2=−veE_{1} + E_{2} = -ve

B

E1+E2=+veE_{1} + E_{2} = +ve

C

E1+E2=0E_{1} + E_{2} = 0

D

None of the above

Step-by-Step Solution

Internal energy (UU or EE) is a state function, meaning its value is determined solely by the current state of the system and is independent of the path taken to reach that state . When a system moves from state A to state B, the change in internal energy is E1=UB−UAE_{1} = U_{B} - U_{A}. When the system returns from state B to state A, the change is E2=UA−UBE_{2} = U_{A} - U_{B}. Summing these changes for the entire cycle (A → B → A) gives E1+E2=(UB−UA)+(UA−UB)=0E_{1} + E_{2} = (U_{B} - U_{A}) + (U_{A} - U_{B}) = 0 . This demonstrates that for any cyclic process, the net change in a state function is zero.

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.

CHEMISTRYThermodynamicssystemchangedanothercorrespondingchanges

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