## Gibbs Free Energy/Equil Constant Relationship

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

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

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

Sydney Wu 2M
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Joined: Fri Jul 22, 2016 3:00 am

### Gibbs Free Energy/Equil Constant Relationship

On page 41 of the course reader, it says delta G* is positive when K<1 and that delta G* is negative when K>1. Does that mean the forward reaction is not spontaneous when K<1 and is when K>1? I understand the arithmetic but I don't understand because if K<1, the reaction will want to go forward (spontaneous forward), and if K>1, then the reaction will want to go in reverse (not spontaneous forward).

Chem_Mod
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### Re: Gibbs Free Energy/Equil Constant Relationship

"On page 41 of the course reader, it says delta G* is positive when K<1 and that delta G* is negative when K>1. Does that mean the forward reaction is not spontaneous when K<1 and is when K>1?"

Correct

"I understand the arithmetic but I don't understand because if K<1, the reaction will want to go forward (spontaneous forward), and if K>1, then the reaction will want to go in reverse (not spontaneous forward)."

These are equilibrium constants, the reaction is not going in any direction. At equilibrium the [R] and [P] don't change.