total entropy of the system


Moderators: Chem_Mod, Chem_Admin

Sophie Krylova 2J
Posts: 59
Joined: Fri Sep 29, 2017 7:06 am

total entropy of the system

Postby Sophie Krylova 2J » Fri Mar 16, 2018 11:13 pm

The second law states that the total entropy of an isolated system always increases. At the same time we talk about how if total entropy is negative, the reaction is not spontaneous or if it's zero, the rxn is at equilibrium. How are these two scenarios possible in the light of the second law, stating that the entropy can only increase?

melissa carey 1f
Posts: 53
Joined: Fri Sep 29, 2017 7:06 am

Re: total entropy of the system

Postby melissa carey 1f » Sat Mar 17, 2018 10:44 am


OliviaShearin2E
Posts: 37
Joined: Fri Sep 29, 2017 7:05 am

Re: total entropy of the system

Postby OliviaShearin2E » Sat Mar 17, 2018 10:57 am

The second law does not mean that entropy always increases, but that entropy can never decrease. If total entropy is negative, the reaction is not spontaneous as you said. This means the reverse reaction is spontaneous so the total entropy increases. When the reaction is at equilibrium, the entropy is zero so it does not decrease.

Troy Tavangar 1I
Posts: 50
Joined: Fri Sep 29, 2017 7:04 am

Re: total entropy of the system

Postby Troy Tavangar 1I » Sun Mar 18, 2018 1:20 am

The second law only says that the entropy can never decrease which is why entropy itself is never negative


Return to “Concepts & Calculations Using Second Law of Thermodynamics”

Who is online

Users browsing this forum: No registered users and 2 guests