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MHT CET2019Morning ShiftChemistryThermodynamics (C)Actual

Based on first law of thermodynamics which of the following is correct

Options

  1. AFor an isobaric process, q p = Δ U + w
  2. BFor an adiabatic process, Δ U = - w
  3. CFor an isochoric process, Δ U = - q v
  4. DFor an isothermal Process, q = + w

Correct answer

A. For an isobaric process, q p = Δ U + w

Step-by-step solution

In isobaric process, pressure is constant and volume increase from V 1 to V 2 due to the absorption of heat. According to the first law of thermodynamics, Δ U = q + W At constant pressure, q p = Δ U - W q p = Δ U - p Δ V q p = U 2 - U 1 - - p V 2 - V 1 q p = U 2 + p V 2 - U 1 + p V 1 q p = H 2 - H 1 q p = Δ H . . . ( i ) As we know, Δ H = Δ U + p Δ V Δ H = Δ U + W Putting the value of Δ H in (1) q p = Δ U + W Other corrected options are as follows: • For adiabatic process, Δ U = W • For an isochoric process, Δ U =

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