Calculate the entropy change in the system, and in the surroundings and the total entropy change in the universe when during a process 75 J of heat flow out of the system at 55^(@)C to the surrounding at 20^(@)C.

Calculate the entropy change in the system, and in the surroundings an

1.	Calculate the entropy change in the system, and in the surroundings and the total entropy change in the universe when during a process 75 J of heat flow out of the system at 55^(@)C to the surrounding at 20^(@)C.
Answer» Solution :HEAT FLOW (q) = 75 J Entropy change = `DeltaS`= ? Temperature of the system =`55^@C+273` = 328 K Temperature of the surroundings =`20^@C`+273 =293 K `DeltaS_"system"=q/T_"system"=75/328=0.2286 "J K"^(-1)` `DeltaS_"surroundings"=q/T_"surroundings"=75/293=0.2559 J K^(-1)` `DeltaS_"UNIVERSE"`=Entropy change =`DeltaS_"system"+DeltaS_"surroundings"` =0.2286+0.2559 `DeltaS_"universe"=0.4845 JK^(-1)`