## Signs for Gibbs Free Energy

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

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

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

Abigail Menchaca_1H
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### Signs for Gibbs Free Energy

What does it mean when Gibbs Free Energy is negative or positive?

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### Re: Signs for Gibbs Free Energy

When the Gibbs Free Energy is negative it means that the forward reaction is spontaneous while if it is positive, it means that the reverse reaction is spontaneous.

Kimberly Koo 2I
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### Re: Signs for Gibbs Free Energy

If Gibbs free energy is negative, then the process is spontaneous in the forward direction. If the Gibbs free energy is positive, then the process is nonspontaneous in the forward direction and spontaneous in the reverse direction.

SVajragiri_1C
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### Re: Signs for Gibbs Free Energy

When G is negative, the reaction is spontaneous and thermodynamically stable, and if G is positive the reaction is non-spontaneous and thermodynamically unstable. You can calculate this using the equation G = H - TS.

Louise Lin 2B
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### Re: Signs for Gibbs Free Energy

A negative deltaG means that the reaction is spontaneous, and usually exothermic. A positive delta G means that the reaction is nonspontaneous, and usually endothermic.

kausalya_1k
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### Re: Signs for Gibbs Free Energy

When deltaG is less than 0 (negative) the forward reaction is spontaneous. When deltaG is positive, the reverse reaction is spontaneous. When deltaG=0, the system is at equilibrium.

Shail Avasthi 2C
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### Re: Signs for Gibbs Free Energy

When ΔG is positive, the reaction is non-spontaneous and requires an input of energy to proceed towards the products. When ΔG is negative, the reaction is spontaneous and releases energy as it proceeds towards the products.

Mariah
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### Re: Signs for Gibbs Free Energy

Prasanna Padmanabham 4I wrote:When the Gibbs Free Energy is negative it means that the forward reaction is spontaneous while if it is positive, it means that the reverse reaction is spontaneous.

Spontaneous means that it will occur on its own correct?

Katie Bart 1I
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### Re: Signs for Gibbs Free Energy

It also helps me to think of the signs in terms of energy being absorbed and released.

Jasmine Fendi 1D
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### Re: Signs for Gibbs Free Energy

When the sign is negative, it means that the reaction is spontaneous. That is because the reaction would result in molecules being in their most stable state which would require less energy to maintain the bonds. As a result, the overall energy is negative because energy is being released. The same is for the opposite. When the sign is positive, the reaction is not spontaneous and therefore requires energy.

lauraxie2e
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### Re: Signs for Gibbs Free Energy

negative is exothermic and positive is endothermic

Kallista McCarty 1C
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### Re: Signs for Gibbs Free Energy

Negative is spontaneous (exothermic) and positive is not spontaneous (endothermic)