## 11.17

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

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

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

josephyim1L
Posts: 61
Joined: Fri Sep 28, 2018 12:15 am

### 11.17

Can someone walk through this question with me:

11.17 (a) Calculate the reaction Gibbs free energy of N2(g) ->3 H2(g) S 2 NH3(g) when the partial pressures of N2, H2, and NH3 are 4.2 bar, 1.8 bar, and 21 bar, respectively, and the temperature is 400. K. For this reaction, K = 41 at 400. K. (b) Indicate whether this reaction mixture is likely to form reactants, is likely to form products, or is at equilibrium.

Chem_Mod
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### Re: 11.17

The problem gives you information about the K value and concentrations that can be used to get the Q value. ΔG = ΔG0 + R*T*ln(Q) can then be used to calculate the ΔG.

Danny Zhang 4L
Posts: 62
Joined: Fri Sep 28, 2018 12:26 am

### Re: 11.17

Going further with the directions that is provided, you can calculate ΔG^(o) with the K given to you through -RTln(K).
Last edited by Danny Zhang 4L on Thu Feb 28, 2019 9:32 pm, edited 1 time in total.

Carissa Young 1K
Posts: 65
Joined: Fri Sep 28, 2018 12:17 am

### Re: 11.17

Since the reaction is not at equilibrium, you need to use deltaG=deltaGo + RTlnQ which can be further written as deltaG=-RTlnK + RTlnQ