Question:easy
A perfect gas expands reversibly at a constant temperature of 298 K so that its volume doubles. What is the change in the molar internal energy of the gas?
A perfect gas expands reversibly at a constant temperature of 298 K so that its volume doubles. What is the change in the molar internal energy of the gas?
Show Hint
Internal energy of an ideal gas depends only on temperature (Joule's law).
Updated On: Jul 3, 2026
- +2.27 kJ/mol
- 0 J/mol
- +1.72 kJ/mol
- -2.27 kJ/mol
Show Solution
The Correct Option is B
Solution and Explanation
Kinetic theory: internal energy is purely kinetic, depending only on T. No intermolecular forces for ideal gas. Since T unchanged, U unchanged.
\[\boxed{\Delta U = 0\ J/mol}\]Was this answer helpful?
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