## entropy to surroundings

$\Delta G^{\circ}= \Delta H^{\circ} - T \Delta S^{\circ}$

$\Delta G^{\circ}= -RT\ln K$

$\Delta G^{\circ}= \sum \Delta G_{f}^{\circ}(products) - \sum \Delta G_{f}^{\circ}(reactants)$

Emily Glaser 1F
Posts: 156
Joined: Thu Jul 27, 2017 3:01 am

### entropy to surroundings

The second law states that disorder is always increasing, thus if I have a reaction with decreasing entropy, then the surroundings would have increases entropy. How would I calculate this

Angel Gomez 1K
Posts: 36
Joined: Fri Sep 29, 2017 7:04 am

### Re: entropy to surroundings

Because the entropy lost by the reaction goes to the surroundings, and the surroundings are gaining the entropy, this means that the entropy gained by the surroundings is equal to that lost by the reaction. If the entropy for the reaction decreased by 1 J/K (-1 J/K), for example, then the entropy of the surroundings would increase by 1 J/K (+1 J/K). This fulfills the equation deltaS(total)=deltaS(surroundings)+deltaS(system).

Julia Cheng 2J
Posts: 31
Joined: Thu Jul 13, 2017 3:00 am

### Re: entropy to surroundings

Keep in mind that the second law is referring to the total entropy, aka the entropy of the universe. So, the entropy of the system or of the surroundings can increase without violating the second law as long as the total entropy is not negative.

Lauren Seidl 1D
Posts: 51
Joined: Fri Sep 29, 2017 7:06 am

### Re: entropy to surroundings

The easiest way is that deltaS(total) = deltaS(system) + deltaS(surroundings), and deltaS(total) must be 0 for a system at equilibrium, so deltaS(system) = -deltaS(surroundings).