Calculate the entropy change in the system and surroundings, and the total entropy change in the universe during a process in which 245 J of heat flow out of the system at 77^@C to the surrounding at 33^@C.

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

1.	Calculate the entropy change in the system and surroundings, and the total entropy change in the universe during a process in which 245 J of heat flow out of the system at 77^@C to the surrounding at 33^@C.
Answer» Solution :Given `T_"SYS"=77^@C =(77+273)`=350 K `T_"surr"=33^@C` =(33+273) =306 K q=245 J `DeltaS_"sys" =q/T_"sys" =(-245)/350=-0.7 JK^(-1)` `DeltaS_"UNIV"=q/T_"sys" =(+245)/350=+0.8 JK^(-1)` `DeltaS_"univ"=DeltaS_"sys" +DeltaS_"surr"` `DeltaS_"univ"=-0.7 JK^(-1) + 0.8 JK^(-1)` `DeltaS_"univ" =0.1 JK^(-1)`