## Spontaneous

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

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

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

eduardomorales5
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### Spontaneous

How do we determine if a reaction is spontaneous? What does having a Gibbs free energy of 0 mean relative to the energy of the reaction?

Victoria Zheng--2F
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### Re: Spontaneous

A reaction will be spontaneous if the change in Gibbs Free energy is a negative value. A reaction will not be spontaneous if the change in Gibbs Free energy is a positive value.

Elizabeth Harty 1A
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### Re: Spontaneous

You can look at the sign of delta g. If it is negative its spontaneous if its positive its not.

CameronDis2K
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### Re: Spontaneous

a negative delta G (corresponding to a positive delta S) correlates to a spontaneous reaction, while a positive is vice versa. If the delta G is 0, the system will have reached equilibrium, and the forward and backward rates are the same.

Uisa_Manumaleuna_3E
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### Re: Spontaneous

professor lavelle said that every time we're asked whether or not something is spontaneous we know that delta g has to be negative. that's it really.

Tiffany_Chen 2K
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### Re: Spontaneous

When deltaG (free energy available to do work) is negative!

Jialun Chen 4F
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### Re: Spontaneous

The sign of Gibb's free energy determines the spontaneity of a reaction.

Kishan Shah 2G
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### Re: Spontaneous

A negative delta G value or a positive detla S universe (total) value.

Justin Seok 2A
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### Re: Spontaneous

A reaction that is spontaneous will have a negative Gibbs free energy, while a reaction that has a Gibbs free energy is in equilibrium.

Connor Chappell 2B
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### Re: Spontaneous

If the change in gibbs free energy is negative, the reaction is spontaneous. If it is positive, it is not. It the change in gibbs free energy is equal to 0, the reaction is in equilibrium.

805373590
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### Re: Spontaneous

If our delta g is negative then the reaction is spontaneous in the forward direction.

Maya Beal Dis 1D
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### Re: Spontaneous

It delta G is positive it means the reaction is spontaneous in the reverse direction.

Jialun Chen 4F
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### Re: Spontaneous

DeltaG's sign determines spontaneity. If positive, not spontaneous; if negative, spontaneous; if =0, at equilibrium.

Posts: 102
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### Re: Spontaneous

A reaction will be spontaneous if the Gibbs free energy value is negative. So to find that point you would set the equation to zero to solve and then say that all values less that the one you find will make the reaction spontaneous.

Daria MacAuslan 1H
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### Re: Spontaneous

When the change in Gibbs Free Energy value is negative, then we can know that the reaction is spontaneous and proceeding towards the products. If it is a positive change, then the reaction is not favorable or spontaneous and proceeds towards reactants.

Abby Soriano 1J
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### Re: Spontaneous

A reaction is spontaneous if it has a negative delta G (meaning it also proceeds in the forward direction towards the products). When delta G is 0, the reaction is at equilibrium since the free energy of the products equals the free energy of the reactants and no more work can be done.

Brandon Valafar
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### Re: Spontaneous

If the delta G value is negative, then it is spontaneous toward the forward direction.

Alison Trinh 1E
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### Re: Spontaneous

If DeltaG is less than 0 at a certain composition of the reaction mixture, then the forward reaction is spontaneous. If DeltaG is greater than 0 at a certain composition of the reaction mixture then the reverse reaction is spontaneous.

Dan M -3E
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### Re: Spontaneous

If deltaG is equal to 0, than the reaction is at equilibrium, and not proceeding in either direction.

san_2F
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### Re: Spontaneous

if delta G is less than 0, that means the reaction is spontaneous. You can also think of spontaneity in terms of the equation delta G= delta H - T*Delta S in order to assess which values of delta H and delta S can produce a spontaneous reaction with a negative delta G.

Jesalynne 2F
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### Re: Spontaneous

When delta G is negative the reaction is spontaneous, but when delta G is positive the reaction is not spontaneous. When delta G is equal to 0 then the reaction is not spontaneous because it is at equilibrium.

Omar Selim 1D
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### Re: Spontaneous

In order for a reaction to be considered spontaneous, the value of delta G must be a negative number. delta g = delta H - TDELTAS. If delta g is 0, the reaction is at equilibrium.

Posts: 74
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### Re: Spontaneous

Here is an image that can help!
Attachments

Emil Velasco 1H
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### Re: Spontaneous

Gibbs Free Energy being at zero signals that the reaction is at equilibrium