## HW #11.15 - Calculating reaction Gibbs Free Energy

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

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

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

Jeana Wei 3C
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### HW #11.15 - Calculating reaction Gibbs Free Energy

Calculate the reaction Gibbs free energy of I2(g) -> 2 I(g) at 1200. K (K = 6.8) when the partial pressures of I2 and I are 0.13 bar and 0.98 bar, respectively.

I know I need to use the equation deltaG = deltaG(standard) + RTln(Q) and to find deltaG(standard) by using equation deltaG(standard) = -RTlnK. I'm given K, but which values do I use for R and T? Do I use T = 298 K to find the standard delta G and then use T = 1200K when I'm solving for deltaG in the first equation written above? Also, which value do I use for R?

Thanks!

Chem_Mod
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### Re: HW #11.15 - Calculating reaction Gibbs Free Energy

what you think is correct and R is 8.314