## standard vs reaction gibbs free energy [ENDORSED]

$\Delta G^{\circ} = -nFE_{cell}^{\circ}$

shaunajava2e
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### standard vs reaction gibbs free energy

What’s the difference between standard gibbs free energy and reaction gibbs free energy?

Laura Gong 3H
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### Re: standard vs reaction gibbs free energy

Standard Gibbs free energy occurs under standard conditions (1M, 1atm, 298K or 25C). I think reaction Gibbs free energy is just referring the free energy of a particular reaction which may or may not occur under standard conditions.

Chem_Mod
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### Re: standard vs reaction gibbs free energy  [ENDORSED]

Yes, except the temperature is not stipulated in standard Gibbs free energy, $\Delta G^\circ$, just the concentration or pressure of each species. We often report the standard Gibbs free energy change for a reaction, $\Delta G_{r}^\circ$, though we often just write it as the standard Gibbs free energy change, $\Delta G^\circ$.

shaunajava2e
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### Re: standard vs reaction gibbs free energy

more specifically i’m referring to questions 11.15 and 11.21 6th ed, they’re the same reaction occurring at the same temp, but one asks for the standard gibbs (and gives the k value only) while the other asks for the reaction gibbs (giving both k and the partial pressures).

so what i’m understand is that when it asks for the reaction gibbs free energy it’s based on the current state of the reaction most likely not at equilibrium using the reaction quotient right??