Kp vs Kc

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jane_ni_2d
Posts: 67
Joined: Fri Sep 28, 2018 12:23 am

Kp vs Kc

Postby jane_ni_2d » Fri Jan 11, 2019 5:16 pm

Is one of Kp or Kc more important?

Lopez_Melissa-Dis4E
Posts: 66
Joined: Fri Sep 28, 2018 12:20 am

Re: Kp vs Kc

Postby Lopez_Melissa-Dis4E » Fri Jan 11, 2019 5:51 pm

I believe it's a matter of what the question is asking. I would assume that they are equally important.

Diana Bibireata 1B
Posts: 60
Joined: Fri Sep 28, 2018 12:23 am

Re: Kp vs Kc

Postby Diana Bibireata 1B » Fri Jan 11, 2019 6:10 pm

Both are equally important. But keep in mind that Kp is only used for gases while Kc can be used for gases and aqueous solutions.

JadeSebti1L
Posts: 35
Joined: Fri Sep 28, 2018 12:19 am

Re: Kp vs Kc

Postby JadeSebti1L » Fri Jan 11, 2019 6:12 pm

Yes, Kc or Kp totally depends on the question you're asked. If the formula uses gases, use Kp for partial pressure instead of concentration. If you want to find Kc after, you have to a derivation of Kc in terms of Kp using PV=nRT.

Ray Guo 4C
Posts: 90
Joined: Fri Sep 28, 2018 12:15 am

Re: Kp vs Kc

Postby Ray Guo 4C » Fri Jan 11, 2019 6:14 pm

In a reaction that only involves gases, Kp is much more useful than Kc.

LilyL1C
Posts: 24
Joined: Fri Sep 28, 2018 12:20 am

Re: Kp vs Kc

Postby LilyL1C » Fri Jan 11, 2019 6:44 pm

It really depends on the question. If the equation is comprised of only gases and they are asking you to find the equilibrium constant, then you should use Kp. But even if the equation only has gases, and they give you the concentrations of the compounds, it's easier to use Kc. You could still convert the concentrations into pressures using PV=nRT, but it would just be more work.

Erin Kim 2G
Posts: 75
Joined: Fri Sep 28, 2018 12:26 am

Re: Kp vs Kc

Postby Erin Kim 2G » Fri Jan 11, 2019 7:01 pm

neither is more important, it depends on the situation. You use kp for partial pressure, and kc for when the concentration is given.


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