When to use Kp or Kc

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Searra Harding 4I
Posts: 68
Joined: Fri Sep 28, 2018 12:29 am

When to use Kp or Kc

Postby Searra Harding 4I » Thu Jan 10, 2019 10:54 pm

If a question asks to find K, how do we know whether to make our answer Kp or Kc? I thought that if it is all gases then you use Kp but we have examples where we do the opposite.

Kate Chow 4H
Posts: 61
Joined: Fri Sep 28, 2018 12:28 am

Re: When to use Kp or Kc

Postby Kate Chow 4H » Thu Jan 10, 2019 11:12 pm

I'm also a little confused about this, but I'm pretty sure that you use Kp for gasses unless the problem specifically tells you to use Kc. Also, in some problems, you can determine whether to use Kp or Kc depending on the units given. I know there are instances of this in the assigned problems.

Kessandra Ng 1K
Posts: 67
Joined: Fri Sep 28, 2018 12:25 am

Re: When to use Kp or Kc

Postby Kessandra Ng 1K » Thu Jan 10, 2019 11:26 pm

I also thought that you only use Kp if all the the reactants and products in the reaction are gases, but usually they specify whether they want you to use Kp or Kc in the textbook homework questions so I assume Dr. Lavelle will do the same on his tests also.

GavinAleshire1L
Posts: 29
Joined: Fri Sep 28, 2018 12:21 am

Re: When to use Kp or Kc

Postby GavinAleshire1L » Fri Jan 11, 2019 12:58 am

In terms of the textbook I believe they use K and Kp interchangeably, but I'm not sure if this applies to everything. I think further clarification would be helpful.


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