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Thermodynamic property: identify U + p·v Select the thermodynamic property defined as the sum of internal energy (U) and the product of pressure and volume (p·v). Choose the correct option.

Difficulty: Easy

workdone
entropy
enthalpy
none of these

Correct Answer: enthalpy

Explanation:

Concept
Enthalpy is defined as H = U + p v. It is especially convenient for open systems (flow processes) at approximately constant pressure, where enthalpy changes track heat transfer.

Why others are incorrect
Work is a path function; entropy (S) is a different state function relating heat transfer and temperature.

Final Answer
enthalpy

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