Gibbs Free energy concept






Moderators: Chem_Mod, Chem_Admin

kennedyp
Posts: 56
Joined: Tue Nov 13, 2018 12:18 am

Gibbs Free energy concept

Postby kennedyp » Fri Feb 14, 2020 8:52 am

So this might sound bad especially since we just took our midterm on it, but I'm still having a little trouble understanding exactly what Gibbs free energy is? Like what does it tell us about a system or the surroundings and why is it an important concept to know for chemistry? I can do the equations and stuff, but I still don't really understand it.

Kaitlyn Ang 1J
Posts: 116
Joined: Fri Aug 09, 2019 12:17 am
Been upvoted: 1 time

Re: Gibbs Free energy concept

Postby Kaitlyn Ang 1J » Fri Feb 14, 2020 9:44 am

The definition given in class is that Gibbs free energy is the energy given off that’s now available (“free”) to do work. Basically, if deltaG is negative, that means it gives off energy that is now “free” to do work, which results in a spontaneous reaction. The important thing to know is that when deltaG is negative, the reaction is spontaneous and when deltaG is positive, the reaction is spontaneous.

Amy Pham 1D
Posts: 103
Joined: Fri Aug 09, 2019 12:15 am

Re: Gibbs Free energy concept

Postby Amy Pham 1D » Fri Feb 14, 2020 10:15 am

Negative values of deltaG indicate that the reaction has the free energy to carry out the process, and thus the reaction proceeds spontaneously. Positive values of deltaG indicate a nonspontaneous reaction, as it does not have the free energy necessary to allow the reaction to proceed.

Zoe Gleason 4F
Posts: 51
Joined: Tue Jul 23, 2019 12:15 am

Re: Gibbs Free energy concept

Postby Zoe Gleason 4F » Fri Feb 14, 2020 10:22 am

It shows how much energy is available to do work. It is really important in determining if the reaction is spontaneous (ΔG-). A reaction could be spontaneous if it becomes more disordered, if energy is released, or both. The negative value shows that product formation will be favored.

ThomasNguyen_Dis1H
Posts: 102
Joined: Fri Aug 30, 2019 12:17 am

Re: Gibbs Free energy concept

Postby ThomasNguyen_Dis1H » Fri Feb 14, 2020 11:21 am

It basically represents the amount of energy available to do work. It also tells you if a reaction is favorable (spontaneous) or unfavorable(not spontaneous). If G is negative then it will be favorable.

MeeraBhagat
Posts: 95
Joined: Sat Aug 24, 2019 12:15 am

Re: Gibbs Free energy concept

Postby MeeraBhagat » Fri Feb 14, 2020 4:25 pm

Free energy is the energy that is available to do work, and Delta G is useful for telling us if the current state of a process is spontaneous (-delta G and system will do work) or not spontaneous (wont do work).

Sally Qiu 2E
Posts: 105
Joined: Fri Aug 30, 2019 12:18 am

Re: Gibbs Free energy concept

Postby Sally Qiu 2E » Fri Feb 14, 2020 5:13 pm

gibbs free energy is basically the energy that is available to do work, hence "free" energy.

Diana Chavez-Carrillo 2L
Posts: 122
Joined: Fri Sep 28, 2018 12:18 am

Re: Gibbs Free energy concept

Postby Diana Chavez-Carrillo 2L » Fri Feb 14, 2020 6:09 pm

Gibbs Free Energy ( ∆G ) is the energy of a system that is free to do work at a constant temperature and pressure. Gibbs free energy is a state function and an extensive property. It gives us information about the spontaneity of a reaction. Spontaneity is when a reaction is naturally occurring. The more negative ∆G° reaction is the more spontaneous the reaction (the more likely that it will occur). ∆G° is temperature dependent when ∆H° and ∆S° have the same sign.

Ruth Glauber 1C
Posts: 100
Joined: Wed Sep 18, 2019 12:20 am

Re: Gibbs Free energy concept

Postby Ruth Glauber 1C » Sat Feb 15, 2020 7:15 am

Gibbs free energy is the energy that is available to do work. Delta G indicates if it is spontaneous!

Kristina Rizo 2K
Posts: 105
Joined: Wed Sep 18, 2019 12:19 am

Re: Gibbs Free energy concept

Postby Kristina Rizo 2K » Sat Feb 15, 2020 11:39 am

Looking at the graph that lavelle made on Friday helped me understand more by visualizing how -delta G is spontaneous while + delta G is non-spontaneous.
DEC3D6A7-66D2-463B-B718-FB8D18F6C677.jpeg

Madeline Phan 1E
Posts: 103
Joined: Sat Aug 17, 2019 12:18 am

Re: Gibbs Free energy concept

Postby Madeline Phan 1E » Sat Feb 15, 2020 4:43 pm

Gibb's free energy is the amount of energy available to do work. It is also the prime indicator of whether a reaction is favorable (spontaneous) or not.

Veronica Lu 2H
Posts: 89
Joined: Wed Sep 18, 2019 12:18 am
Been upvoted: 1 time

Re: Gibbs Free energy concept

Postby Veronica Lu 2H » Sun Feb 16, 2020 11:39 am

Gibbs free energy is the energy available to do work. A negative delta G indicates spontaneity whereas positive delta G means it’s not spontaneous

905373636
Posts: 62
Joined: Thu Aug 01, 2019 12:15 am

Re: Gibbs Free energy concept

Postby 905373636 » Sun Feb 16, 2020 11:41 am

The Gibbs free energy can predict the spontaneity of a reaction at different circumstances / environmental conditions. In this way, it can predict at what temperature -- for example -- a reaction becomes spontaneous if all other factors are constant.

Radha Patel 4I
Posts: 97
Joined: Tue Feb 12, 2019 12:15 am

Re: Gibbs Free energy concept

Postby Radha Patel 4I » Sun Feb 16, 2020 12:12 pm

Lavelle mentioned on Friday that Gibbs Free Energy is related to spontaneity and nonspontaneity. In lecture he showed a graph that shows the decrease in Gibbs free energy to increasing Gibbs free energy. When deltaG decreases, it is called a spontaneous reaction. One way to represent this reaction is by knowing that this is where the reactant quotient is relevant. When deltaG increases, it is a non spontaneous reaction, this is also where the reaction quotient is prevalent. When deltaG is neither increasing or decreasing, we say that the process is at equilibrium , which is related to k as well.

Ying Yan 1F
Posts: 101
Joined: Fri Aug 02, 2019 12:16 am

Re: Gibbs Free energy concept

Postby Ying Yan 1F » Sun Feb 16, 2020 12:59 pm

The basic concept of Gibbs free energy is the energy *available* to do work by a system. It also tells us the spontaneity of a reaction, (another work to describe it is if the reaction is thermodynamically favorable). If delta G is negative, that means the reaction is spontaneous, and if delta G is positive, then the reaction is not spontaneous. The main equation that you should know about Gibbs free energy is delta G= delta H- T*delat S. I hope this helps!

Anish Natarajan 4G
Posts: 51
Joined: Thu Jul 25, 2019 12:16 am

Re: Gibbs Free energy concept

Postby Anish Natarajan 4G » Sun Feb 16, 2020 1:03 pm

Gibbs Free Energy is basically a measure of the energy available to do work. In a more practical sense, if the delta G is negative, then there will be more energy available to do work instead of being contained within the chemical bonds of the product as potential energy; these types of reactions are spontaneous.

Andres Merlos 2L
Posts: 46
Joined: Wed Sep 18, 2019 12:17 am

Re: Gibbs Free energy concept

Postby Andres Merlos 2L » Sun Feb 16, 2020 3:23 pm

Gibbs Free Energy is the amount of energy available to do work. A negative value would indicate spontaneity. A positive value would indicate non-spontaneity.


Return to “Gibbs Free Energy Concepts and Calculations”

Who is online

Users browsing this forum: No registered users and 1 guest