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COMEDK2025ChemistryThermodynamics (C)Actual

Two moles of an ideal gas at 1 bar pressure and 298 K is expanded into vacuum to double the volume. The work done is:

Options

  1. A2 J
  2. B10 J
  3. C0 J
  4. D1.5 J

Correct answer

C. 0 J

Step-by-step solution

The expansion of an ideal gas into vacuum is known as free expansion. In free expansion, the external pressure P_ ext is equal to 0 bar. The formula for work done in a thermodynamic process is given by W = - P_ ext dV . Since P_ ext = 0 , the integral becomes W = - 0 dV = 0 . Therefore, the work done during the expansion of the gas into vacuum is 0 J. Answer: 0 J

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