## 2011 midterm q4

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

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

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

Miya Eberlein 1J
Posts: 29
Joined: Fri Sep 25, 2015 3:00 am

### 2011 midterm q4

i was just wondering, when solving for K, why the product concentration is 2x and not just x? thank you!

Jamlah Dalie 1K
Posts: 62
Joined: Fri Sep 25, 2015 3:00 am

### Re: 2011 midterm q4

It's because since it says the partial pressures for each of the reactants is equal to half that of the product, you'd have a one half in the denominator multiplied to the reactants so it's the same as multiplying the numerator by 2, by rules of fractions.

Taylor Pio 3H
Posts: 21
Joined: Fri Sep 25, 2015 3:00 am

### Re: 2011 midterm q4

I'm confused on why 2x is not the top. Wouldn't each reactant have a 1/2 in front of it? And then wouldn't you bring a 4 to the top instead of a two?

Jamlah Dalie 1K
Posts: 62
Joined: Fri Sep 25, 2015 3:00 am

### Re: 2011 midterm q4

Well you would put the 1/2 on the outside and it would distribute to each reactant, if that makes sense, rather than each having a separate 1/2 and it distributing to the top as 4.