## Gibbs Free Energy and Entropy

$\Delta G^{\circ}= \Delta H^{\circ} - T \Delta S^{\circ}$

$\Delta G^{\circ}= -RT\ln K$

$\Delta G^{\circ}= \sum \Delta G_{f}^{\circ}(products) - \sum \Delta G_{f}^{\circ}(reactants)$

Sophia_Kiessling_2L
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### Gibbs Free Energy and Entropy

Does a negative deltaG mean that the entropy is always lower? Just wondering because the textbook says that a solid has a lower G value than a liquid or gas.

Chem_Mod
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### Re: Gibbs Free Energy and Entropy

for a negative delta G, the sign of delta S can be both positive or negative

Riley Dean 2D
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### Re: Gibbs Free Energy and Entropy

It doesn’t always mean that entropy is lower, you could have different sign combinations for enthalpy and entropy causing the negative delta G

Anmol_cheema_2F
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### Re: Gibbs Free Energy and Entropy

The sign of delta G is dependent on enthalpy, temperature, and entropy so entropy doesn't necessarily have to be negative; it depends on all three.

Hilda Sauceda 3C
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### Re: Gibbs Free Energy and Entropy

No in that case its dependent on the Temp, enthalpy and entropy so it can be + or -.

yuetao4k
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### Re: Gibbs Free Energy and Entropy

The other variable in the ghost equation also factor in whether or not delta S is positive or negative.

Nghi Nguyen 2L
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### Re: Gibbs Free Energy and Entropy

there are a lot of variables that affect delta G, so entropy could be positive or negative

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