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JEE Main20252 Apr 2025Morning ShiftChemistryThermodynamics (C)Actual

Two vessels A and B are connected via stopcock. The vessel A is filled with a gas at a certain pressure. The entire assembly is immersed in water and is allowed to come to thermal equilibrium with water. After opening the stopcock the gas from vessel A expands into vessel B and no change in temperature is observed in the thermometer. Which of the following statement is true?

Options

  1. A(d w 0 )
  2. B( dq 0 )
  3. C( dU 0 )
  4. DThe pressure in the vessel (B ) before opening the stopcock is zero.

Correct answer

D. The pressure in the vessel (B ) before opening the stopcock is zero.

Step-by-step solution

It is free expansion of gas ( P_ ext =0 ) Where ( w =0, q =0 ) and ( U =0 )

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