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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.
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.
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.
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.
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.
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).
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.
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.
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.
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!
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.
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