Sonntag, Borgnakke and van Wylen
8.8 A substance has heat transfer out. Can you say anything about changes in s if the process is reversible? If it is irreversible? Reversible:
dq ds = T < 0
Irreversible:
dq ds = T + dsgen = ?
since
dq < 0 dq < 0
but
dsgen > 0
You cannot say, ds depends on the magnitude of dq/T versus dsgen