1. D

    entropy change adiabatic expansion

    Hello all, this may be a silly question , but for some reason I can't seem to find an explanation anywhere... When an adiabatic process is reversible, why is the entropy=0 (which is not true for an irreversible) using equation, I understand why this is true (since Q=0) but conceptually I'm...
  2. P

    Adiabatic entropy change

    For an adiabatic process dQ=0, there is no heat exchange with the surroundings, therefore dS(surroundings)=0. For expansion of an ideal gas, so the dS(total) must either be = 0 (in the case of a reversible change) or it must increase (second law). In the case of the dS(total) increasing the...
  3. J

    Adiabatic Enthalpy Change

    I got a bit stuck on a practice question I was doing regarding enthalpy change: The temperature of one mole of gas was increased adiabatically from 273K to 548K (Cvm = 20.8J/k/mol). For the system calculate the change in enthalpy (∆H). So obviously ∆Q = 0 as it is adiabatic and therefore the...