Kc & Kp

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Diana Andrade_4F
Posts: 50
Joined: Tue Nov 05, 2019 12:18 am

Kc & Kp

Postby Diana Andrade_4F » Thu Jan 16, 2020 10:18 pm

How do you know when to use Kc or Kp when dealing with gasses? For example, in problem 5I.17 we use Kc instead of Kp, why?

Anthony Hatashita 4H
Posts: 103
Joined: Wed Sep 18, 2019 12:21 am

Re: Kc & Kp

Postby Anthony Hatashita 4H » Thu Jan 16, 2020 10:33 pm

I think we use Kp when all of the reactants and products are gases.

Letty Liu 2C
Posts: 105
Joined: Fri Aug 09, 2019 12:16 am

Re: Kc & Kp

Postby Letty Liu 2C » Fri Jan 17, 2020 10:29 am

It depends on the information we’re given. For 5I.17, the problem gives us Kc so we have to use that.

William Francis 2E
Posts: 101
Joined: Wed Sep 18, 2019 12:20 am

Re: Kc & Kp

Postby William Francis 2E » Fri Jan 17, 2020 10:38 am

I don't think it really matters when the question does not specify which to use. The calculations are the same.

gabbymaraziti
Posts: 111
Joined: Wed Sep 18, 2019 12:19 am

Re: Kc & Kp

Postby gabbymaraziti » Fri Jan 17, 2020 3:23 pm

Can we just use K and not specify Kc or Kp? Or would we be marked down?

Amanda Mei 1B
Posts: 109
Joined: Sat Aug 24, 2019 12:16 am

Re: Kc & Kp

Postby Amanda Mei 1B » Fri Jan 17, 2020 3:41 pm

gabbymaraziti wrote:Can we just use K and not specify Kc or Kp? Or would we be marked down?


I don't think you'll be marked down for using K.

Kavya Immadisetty 2B
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Joined: Sat Aug 24, 2019 12:17 am
Been upvoted: 1 time

Re: Kc & Kp

Postby Kavya Immadisetty 2B » Fri Jan 17, 2020 3:42 pm

gabbymaraziti wrote:Can we just use K and not specify Kc or Kp? Or would we be marked down?


I feel like they won't care on the test. But it can't hurt to take a look at the units and add the C or P.

sarahsalama2E
Posts: 164
Joined: Fri Aug 30, 2019 12:16 am

Re: Kc & Kp

Postby sarahsalama2E » Fri Jan 17, 2020 4:03 pm

You can tell which one to use by what's given in the question; if the values are given in brackets, then you know the values are concentrations rather than partial pressures and you should use Kc.

KnarGeghamyan1B
Posts: 102
Joined: Fri Aug 09, 2019 12:15 am

Re: Kc & Kp

Postby KnarGeghamyan1B » Fri Jan 17, 2020 4:04 pm

Kc is when the numbers given are concentrations while Kp is when the values are partial pressures.

Elizabeth Harty 1A
Posts: 125
Joined: Sat Jul 20, 2019 12:16 am

Re: Kc & Kp

Postby Elizabeth Harty 1A » Fri Jan 17, 2020 4:07 pm

Are the calculations the same regardless of whether its concentration of partial pressure?

805373590
Posts: 101
Joined: Wed Sep 11, 2019 12:17 am

Re: Kc & Kp

Postby 805373590 » Fri Jan 17, 2020 4:59 pm

We use kc when we are dealing with concentrations but we only use kp when we are dealing with partial pressures of gases.

Diana Chavez-Carrillo 2L
Posts: 122
Joined: Fri Sep 28, 2018 12:18 am

Re: Kc & Kp

Postby Diana Chavez-Carrillo 2L » Fri Jan 17, 2020 8:42 pm

Is it possible for there to be an equation with both gaseous particles and aqueous solutions? How would we go about solving this? Would we use a combination of Kc and Kp?

Sreyes_1C
Posts: 90
Joined: Fri Sep 28, 2018 12:19 am

Re: Kc & Kp

Postby Sreyes_1C » Fri Jan 17, 2020 9:32 pm

Elizabeth Harty 1A wrote:Are the calculations the same regardless of whether its concentration of partial pressure?


i believe the calculations are the same so i think its okay as long as you account for any differences in units or something


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