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Questions tagged [free-energy]

Also known as Gibbs energy, it is the enthalpy minus the product of thermodynamic temperature and entropy.

From the IUPAC goldbook, Gibbs energy (function), $G$:

Enthalpy minus the product of thermodynamic temperature and entropy. It was formerly called free energy or free enthalpy.

$$G = H - TS$$

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What is the Gibbs free energy difference between conformational states

In statistical mechanics, for a system of $N$ particles $x_1, \ldots, x_N$ in three dimensions, the Gibbs free energy is defined in terms of the Hamiltonian $H$ as $$ G = -k_\mathrm B T \log \int_{\mathbb{R}^{3N}} \mathrm e^{-H(x_1, \dots,…
Anne Onyme
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Minimizing Gibbs free energy with Helmholtz free energy expressions

If I have an expression for the Helmholtz free energy (from statistical associating fluid theory for a polymer system), can I still find the Gibbs free energy minimum under constant $T,P$ conditions? Seems that since $\mu_i = \left(\frac{\partial…
hatmatrix
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reconciling free energy equations

I am struggling with a very basic concept and I think the issue lies in the definition of standard states. When calculating standard state free energy change via Gibbs equation $$\Delta G^ \circ = \Delta H^\circ – T \Delta S ^\circ$$ one simply…
Andrew U
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Gibbs Free Energy - Maximum Work

I've been having a lot of trouble trying to truly understand Gibbs free energy from a practical perspective. I have no background in physical chemistry, but I think I have a firm grasp on many of the concepts related to Gibbs energy. That being…
James Gargan
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Is work done by a system negative delta G or positive delta G?

My textbook states that a process is spontaneous and can perform work only when it is moving toward equilibrium. Since the process is spontaneous, wouldn't that mean that the work done is attributed to negative free energy? Another way of…
BlueMagic1923
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Relationship between Enthalpy and Gibbs energy

I am a little stuck understanding the difference between Gibbs free energy and enthalpy. Both are measured in Joules and hence some sort of energy. In a chemical reaction where C --> A + B If A and B are more stable, this means energy will be…
Rahim Ahmed
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Why 40J energy was wasted in case of a non spontaneous process by the system?

If there is a system which while undergoing a process produced 30J energy and wasted 40J energy therefore the useful energy was -10J and this explains the process was non spontaneous because ∆G is coming out to be positive where ∆G is negative of…
Sukriti Sharma
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