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JEE Main20198 Apr 2019Morning ShiftChemistryThermodynamics (C)Actual

Which one of the following equations does not correctly represent the first law of thermodynamics for the given processes involving an ideal gas? (Assume non- expansion work is zero)

Options

  1. AIsochoric process : Δ U = q
  2. BIsochoric process : q = – w
  3. CCyclic process : q = – w
  4. DAdiabatic process : Δ U = - w

Correct answer

D. Adiabatic process : Δ U = - w

Step-by-step solution

For cyclic process: Δ U = 0 ⇒ q = - w For isothermal process: Δ U = 0 ⇒ q = - w For adiabatic process: q = 0 ⇒ Δ U = w For isochoric process: w = 0 ⇒ Δ U = q

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