Spontaneous






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eduardomorales5
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Spontaneous

Postby eduardomorales5 » Tue Feb 11, 2020 10:37 pm

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

Postby Victoria Zheng--2F » Tue Feb 11, 2020 10:40 pm

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

Postby Elizabeth Harty 1A » Tue Feb 11, 2020 10:48 pm

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

Postby CameronDis2K » Wed Feb 12, 2020 1:24 pm

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

Postby Uisa_Manumaleuna_3E » Wed Feb 12, 2020 9:29 pm

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

Postby Tiffany_Chen 2K » Wed Feb 12, 2020 9:34 pm

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

Jialun Chen 4F
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Re: Spontaneous

Postby Jialun Chen 4F » Thu Feb 13, 2020 12:04 am

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

Kishan Shah 2G
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Re: Spontaneous

Postby Kishan Shah 2G » Thu Feb 13, 2020 1:21 am

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

Justin Seok 2A
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Re: Spontaneous

Postby Justin Seok 2A » Thu Feb 13, 2020 2:40 am

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

Postby Connor Chappell 2B » Thu Feb 13, 2020 8:40 am

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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Joined: Wed Sep 11, 2019 12:17 am

Re: Spontaneous

Postby 805373590 » Thu Feb 13, 2020 8:59 am

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

Postby Maya Beal Dis 1D » Thu Feb 13, 2020 10:45 am

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

Jialun Chen 4F
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Re: Spontaneous

Postby Jialun Chen 4F » Wed Feb 19, 2020 11:59 pm

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

Max Madrzyk Dis 4G
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Re: Spontaneous

Postby Max Madrzyk Dis 4G » Thu Feb 20, 2020 9:48 am

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

Postby Daria MacAuslan 1H » Thu Feb 20, 2020 11:25 am

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

Postby Abby Soriano 1J » Thu Feb 20, 2020 11:32 am

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

Postby Brandon Valafar » Thu Feb 20, 2020 11:50 am

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

Alison Trinh 1E
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Re: Spontaneous

Postby Alison Trinh 1E » Sun Feb 23, 2020 3:19 pm

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

Postby Dan M -3E » Sun Feb 23, 2020 3:39 pm

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

Postby san_2F » Sun Feb 23, 2020 3:50 pm

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

Postby Jesalynne 2F » Sun Feb 23, 2020 4:01 pm

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

Postby Omar Selim 1D » Sun Feb 23, 2020 4:11 pm

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.

Adriana_4F
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Re: Spontaneous

Postby Adriana_4F » Sun Feb 23, 2020 4:13 pm

Here is an image that can help!
Attachments
Screen Shot 2020-02-23 at 4.10.35 PM.png

Emil Velasco 1H
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Re: Spontaneous

Postby Emil Velasco 1H » Sun Feb 23, 2020 6:10 pm

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


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