Entropy Variation - System, Neighborhood and Universe

jaumzaum

I learned ΔS_univ = ΔS_sys + ΔS_neib

If ΔS_univ > 0 the process is spontaneous.

But ΔS = Q/T right? Shouldn't Q_sys = -Q_neib? (The heat released by the system = - heat released by the neighborhood)
I cannot understand why this is wrong!

If it were the case, ΔS_univ would be always zero

Can anyone help me?

[]`s
John

DrDu

##\Delta S=Q/T## only for reversible processes.For irreversible processes, ##\Delta S>Q/T##.

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jaumzaum Recognitions: Gold Member	Entropy Variation - System, Neighborhood and Universe Tweet I learned ΔS_univ = ΔS_sys + ΔS_neib If ΔS_univ > 0 the process is spontaneous. But ΔS = Q/T right? Shouldn't Q_sys = -Q_neib? (The heat released by the system = - heat released by the neighborhood) I cannot understand why this is wrong! If it were the case, ΔS_univ would be always zero Can anyone help me? []`s John

DrDu Recognitions: Science Advisor	##\Delta S=Q/T## only for reversible processes.For irreversible processes, ##\Delta S>Q/T##.