Question 18
The entropy change of the surroundings, $\Delta S_{surr}$, is related to heat transfer, q, with respect to the system and temperature T by
-q/Tsurr = $\Delta S_{surr}$.
+q/Tsys = $\Delta S_{surr}$.
None of these, unless the system undergoes a reversible process.
-q/Tsys = $\Delta S_{surr}$
q/Tsurr = $\Delta S_{surr}$.