Define Entropy

Volume:
Temperature:

Moderators: Chem_Mod, Chem_Admin

ClaireHW
Posts: 60
Joined: Fri Sep 29, 2017 7:07 am
Been upvoted: 1 time

Define Entropy

Postby ClaireHW » Wed Jan 31, 2018 10:37 pm

What is entropy? Physically what does an entropy change look like?

(Claire Woolson Dis 1K)

ClaireHW
Posts: 60
Joined: Fri Sep 29, 2017 7:07 am
Been upvoted: 1 time

Re: Define Entropy

Postby ClaireHW » Wed Jan 31, 2018 10:38 pm

Can someone also do the same for Gibbs Free Energy?

Thanks!

(Claire Woolson Dis 1K)

Vincent Tse 1K
Posts: 30
Joined: Fri Sep 29, 2017 7:05 am
Been upvoted: 1 time

Re: Define Entropy

Postby Vincent Tse 1K » Wed Jan 31, 2018 11:00 pm

Entropy is a thermodynamic quantity denoted by ΔS, and refers to the "disorder" (an potentially confusing term, if you remember from lecture) of something. In essence, most reactions tend to favor going from low entropy to high entropy (you won't need to put in work). A physical example would be a phase change from solid to liquid.


Gibbs free energy is basically the free energy in a process available to do work. An important relationship to consider is ΔG = ΔH - TΔS, which, if you know the signs of the unknowns, you can determine the sign of ΔG and hence predict if a reaction is favorable or not.

Liz White 1K
Posts: 35
Joined: Thu Jul 13, 2017 3:00 am

Re: Define Entropy

Postby Liz White 1K » Wed Jan 31, 2018 11:25 pm

In summary, entropy is equal to the amount of disorder. Gibbs Free Energy is equal to the enthalpy minus the entropy times the temperature. We can use Gibbs Free Energy to determine whether or not a reaction is spontaneous, as a negative value of G will show spontaneity.

Helen Shi 1J
Posts: 78
Joined: Sat Jul 22, 2017 3:00 am

Re: Define Entropy

Postby Helen Shi 1J » Wed Jan 31, 2018 11:45 pm

Can someone explain why we divide q by temperature?


Return to “Entropy Changes Due to Changes in Volume and Temperature”

Who is online

Users browsing this forum: No registered users and 1 guest