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Which statement is true for every thermodynamic system?

1. The entropy change can never be zero
2. Internal energy and entropy are state functions
3. Internal energy changes in every process
4. The work done during an adiabatic process is always zero

Correct answer: Internal energy and entropy are state functions

Solution

Internal energy and entropy are state functions because their values depend only on the current state of the system, not on the path taken to reach that state. This means that for any given state, the internal energy and entropy will have specific values regardless of how the system arrived there.

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