## Sign of delta G

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

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

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

Aiden Metzner 2C
Posts: 104
Joined: Wed Sep 18, 2019 12:21 am

### Sign of delta G

Instead of using the sign of delta G to determine which way a reaction can proceed. Could we also just figure out if Q is less then or more then K and decide that way?

Renee Grange 1I
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### Re: Sign of delta G

Yes, I think you could do that.

Morgan Carrington 2H
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Joined: Wed Nov 14, 2018 12:22 am

### Re: Sign of delta G

It would make sense to do this, but I guess it also depends on what information is given within the problem. You would need enough information to calculate the K value if it was not already given and that could take more time than you have.

KnarGeghamyan1B
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Joined: Fri Aug 09, 2019 12:15 am

### Re: Sign of delta G

I agree, it depends on if they give you concentrations (use K vs Q) or information to find enthalpy and temperature (use G).

Amy Pham 1D
Posts: 103
Joined: Fri Aug 09, 2019 12:15 am

### Re: Sign of delta G

There are many different methods to determine whether a reaction will proceed to favor reactants or products, or if it is at equilibrium: deltaG and comparing K to Q are two of the many. It all depends on what type of problem it is and what information is given, but yes these are definitely two methods to determine the direction of a given reaction.

Jessica Kwek 4F
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Joined: Mon Jan 06, 2020 7:57 am

### Re: Sign of delta G

Yes, if you have enough information you should be able to use the values of Q and K.

Gurmukhi Bevli 4G
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Joined: Wed Nov 14, 2018 12:20 am

### Re: Sign of delta G

Yes I think thats possible, provided you have been given enough information.

kristi le 2F
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### Re: Sign of delta G

Yes, because one of the equations for delta G depends on Q.

AniP_2D
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Joined: Sat Aug 17, 2019 12:17 am

### Re: Sign of delta G

I believe you can, but just to be safe I would use the sign of G to determine the answer for that.

Pablo 1K
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Joined: Sat Feb 02, 2019 12:15 am

### Re: Sign of delta G

Sign of delta G may be the most relevant info as info relating to K may not be available.

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