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COMEDK20269 May 2026Evening ShiftChemistryThermodynamics (C)Actual

For an ideal gas undergoing an isothermal change, there is

Options

  1. Aan increase in Internal energy of the system and heat absorbed by the system is greater than the work done on
  2. Bno change in Internal energy of the system and heat absorbed by the system is equal to the work done by the sy
  3. Cno change in Internal energy of the system and heat released by the system is equal to the work done by the sy
  4. Da decrease in Internal energy of the system and heat released by the system is equal to the work done by the s

Correct answer

B. no change in Internal energy of the system and heat absorbed by the system is equal to the work done by the sy

Step-by-step solution

For an ideal gas, the internal energy depends only on its temperature. In an isothermal process, the temperature remains constant ( T = 0 ). Therefore, the change in internal energy is zero ( U = 0 ). According to the first law of thermodynamics: Q = U + W Substituting U = 0 , we get: Q = W This implies that the heat absorbed by the system ( Q ) is equal to the work done by the system ( W ). Answer: no change in Internal energy of the system and heat absorbed by the system is equal to the work done by the system

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