[skyblue]

Hi,

You are given this reaction CaCO3 (s)=CaO (s)+CO2 (g)

Compare the equilibrium partial pressure of CO2 (g) with the atmospheric partial pressure of CO2 equal to 10^-3.5 atmospheres. Which way will the reaction go?

Okay...I tried searching for an equation to answer this question and came up with deltaG=-RTlnKp

I don't remember this equation from gen chem, but that was the only equation that fit.

So I calculated the gibbs energy and got 130.9 kj/mol and solved for Kp and got 1.194*10^-23.

So now I just compare that Kp with the 10^-3.5 atms? So if it is smaller than the atmospheric pressure, which way does it go? Left?

[Polytriazole]

To start, your equation has only gotten you part of the way there, but you're on the right track.  Do a unit analysis for the values in the equation you used to see why.  What units is K_p in?  Are these the same units as for the partial pressure of CO₂?

Take another look at the source you got this equation from.  Are there example problems near it that can take you further in the problem? 

As for getting a final answer, once you've gotten your partial pressure of CO₂, look up Le Chatelier's principle and see if that gives you any ideas.