## Delta S

Gabriel Ordonez 2K
Posts: 113
Joined: Sat Jul 20, 2019 12:15 am

### Delta S

What is the difference between Delta S, Delta S (total), and Delta S (surroundings)? How do we apply these concepts on an examination / question?

Alicia Lin 2F
Posts: 83
Joined: Wed Sep 18, 2019 12:17 am

### Re: Delta S

Delta S is the change in the entropy of the system. Delta S (surroundings) is the change in entropy of the surroundings. Delta S (total) is Delta S plus Delta S (Surroundings). In a reversible reaction, delta S (surr) is equal to negative Delta S. In an irreversible reaction, Delta S(surr)=0.

Juliana Chopelas 1A
Posts: 50
Joined: Sat Aug 24, 2019 12:16 am

### Re: Delta S

Delta S is equal to entropy so on a question when asked to calculate entropy you will use a delta s equation. Just normal delta s is the change in entropy, delta s surroundings is the change of entropy in the surroundings, and delta s total is the change of entropy of the surroundings and change of entropy of a system.

Charysa Santos 4G
Posts: 107
Joined: Wed Sep 18, 2019 12:21 am

### Re: Delta S

Delta S of the system is the entropy of the system, Delta S of the surroundings is the entropy of the surroundings (usually just the opposite/negative of Delta S), and the Delta S (total) is 0 for isothermal reversible reactions and is usually equal to Delta S (sys) for irreversible reactions.

J_CHEN 4I
Posts: 54
Joined: Tue Nov 14, 2017 3:01 am

### Re: Delta S

Delta S (sys) is the entropy of the system, Delta S (surr) is the entropy of the surroundings. Delta S (sys) + Delta S (surr) = Delta S(total), where Delta S (total) is the total entropy of both the surroundings and the system.

Anna Chen 1K
Posts: 104
Joined: Thu Jul 25, 2019 12:18 am

### Re: Delta S

Delta S - regular delta S, usually concerns the system of the reaction
Delta S (surroundings) - usually equals negative delta S (system)
Delta S (total) - equals delta (system) + delta (surroundings)

RasikaObla_4I
Posts: 100
Joined: Thu Jul 25, 2019 12:15 am

### Re: Delta S

Delta S is the entropy of the system. Delta S surroundings is the entropy of the surroundings. Delta S total is the entropy of the surroundings and system combined.

205389184
Posts: 100
Joined: Sat Sep 07, 2019 12:18 am

### Re: Delta S

Delta S is equal to the entropy of the system whereas delta Ssurroundings is the entropy of the surroundings and so delta Stot is the entropy of the surroundings and system added together.

Julia Holsinger_1A
Posts: 50
Joined: Tue Feb 26, 2019 12:16 am

### Re: Delta S

When using the equation (delta)S= C ln(T2/T1), How do you know which heat capacity to use?