Textbook Table 5G.2

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Cecilia Cisneros 1F
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Joined: Wed Sep 30, 2020 9:45 pm

Textbook Table 5G.2

Postby Cecilia Cisneros 1F » Wed Jan 06, 2021 9:00 am

When we refer to the textbook table for the homework problems how do we know which equilibrium constant to use? I used a Kc value for a question asking to find the equilibrium concentrations, but the homework used the K value. I assumed that K by itself should only be used for finding partial pressures? (For reference the two values were different for this reaction so I went with Kc rather than K).

OwenSumter_2F
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Re: Textbook Table 5G.2

Postby OwenSumter_2F » Wed Jan 06, 2021 9:15 am

K is the more common equilibrium constant, and as a general rule we will most likely be working with K, as that is what a reaction will tend to level off to.

Darlene Lien 3E
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Joined: Wed Sep 30, 2020 9:37 pm

Re: Textbook Table 5G.2

Postby Darlene Lien 3E » Wed Jan 06, 2021 9:44 am

Hi, so when the homework tells you to look at Table 5G.2 for the K value, you look at the temperature they give you in the problem and then locate the K value that has that respective temperature. Hope this helps!

Lisa Seidl 3H
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Re: Textbook Table 5G.2

Postby Lisa Seidl 3H » Wed Jan 06, 2021 9:55 am

When you are calculating for the equilibrium constant from the thermodynamics table (using Gibbs free energy for example) then you can only use K but other than that you can use Kc if you want to find the equilibrium in terms of molar concentration rather than partial pressure.

Sreeram Kurada 3H
Posts: 88
Joined: Wed Sep 30, 2020 10:00 pm

Re: Textbook Table 5G.2

Postby Sreeram Kurada 3H » Wed Jan 06, 2021 11:00 am

Yeah, I think K is just a general term referring to the equilibrium constant, and Kp and Kc are specific into whether they are calculating for the equilibrium constant based on pressure or concentration.


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