thermodynamically stable

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Katie Bart 1I
Posts: 104
Joined: Sat Aug 24, 2019 12:16 am

thermodynamically stable

Postby Katie Bart 1I » Thu Mar 05, 2020 11:01 pm

What is the easiest way to tell if something is thermodynamically stable?

Daria Azizad 1K
Posts: 116
Joined: Thu Jul 25, 2019 12:15 am

Re: thermodynamically stable

Postby Daria Azizad 1K » Thu Mar 05, 2020 11:43 pm

Thermodynamic stability can be identified by looking at delta G. Something stable will be in its lowest energy form and will therefore be unlikely to react.

005324438
Posts: 51
Joined: Sat Aug 24, 2019 12:16 am

Re: thermodynamically stable

Postby 005324438 » Fri Mar 06, 2020 11:37 am

Thermodynamic stability is determined by somethings Gº value. The lower its Gº, the more stable it is going to be. If it is a reactant in a reaction, then the lower its Gº, the less likely it is going to be a spontaneous reaction.

805373590
Posts: 101
Joined: Wed Sep 11, 2019 12:17 am

Re: thermodynamically stable

Postby 805373590 » Fri Mar 06, 2020 1:24 pm

JD123456 wrote:Kinetic stability basically occurs when the reactants react really slowly. The slower the reaction occurs, the greater the kinetic stability. If you say, "This reaction is kinetically stable," then that implies that the reaction occurs very slowly.

Thermodynamic stability depends on whether or not the reaction is spontaneous. This depends on the change in free energy (ΔG). A thermodynamically stable reaction is one that basically does not react. As a result, it is independent of the pathway between reactants and products.

It's like the diamond example on page 52 of the course reader: The reaction of diamond turning into graphite has a negative ΔG, meaning that it is thermodynamically unstable and will spontaneously occur. However, it will take an extremely long time for this to happen, showing that it is kinetically stable and so kinetics is controlling this reaction rather than thermodynamics. Hope this helps!

Caroline Zepecki
Posts: 101
Joined: Fri Aug 09, 2019 12:16 am

Re: thermodynamically stable

Postby Caroline Zepecki » Sun Mar 08, 2020 10:33 am

When something has a lower delta G, it's in a lower energy form, and thus less likely to react. If it's prone to stay in the lowest energy form, or in reactants, you can tell that it's thermodynamically stable

505316964
Posts: 95
Joined: Thu Jul 11, 2019 12:17 am

Re: thermodynamically stable

Postby 505316964 » Sun Mar 08, 2020 5:41 pm

For something to be thermodynamically stable, it has to be spontaneous right? Even though it will not react

805329408
Posts: 49
Joined: Wed Nov 20, 2019 12:21 am

Re: thermodynamically stable

Postby 805329408 » Sun Mar 08, 2020 5:50 pm

505316964 wrote:For something to be thermodynamically stable, it has to be spontaneous right? Even though it will not react

I think for something to be thermodynamically stable, it is non spontaneous since it is unlikely to move to a higher energy on its own, making it stable thermodynamically. On the other hand, for something to be thermodynamically unstable, it has to be spontaneous.


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