I hope someone in here can help me out of this problem.(adsbygoogle = window.adsbygoogle || []).push({});

I know that for calculating the change in entropy of a system ([tex]\Delta S[/tex]) we can use this formula :

[tex]\Delta S[/tex]=[tex]\int[/tex]δq/T

Well the problem is here, when we calculating ΔS for an adiabatic process we know Q= 0 so ΔS=0 in this process, but why we just can't let Q be equal to zero in a free expansion (while we know that in free expansion W=Q=0) and get to the same result (ΔS=0) for the free expansion process?

I should add that I know ΔS≠ 0 for free expansion process but, you know I just don't know where the problem is in my argument.

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# Free expansion and adiabatic process

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