using Kp vs Kc

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Clarice Chui 2C
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using Kp vs Kc

Postby Clarice Chui 2C » Fri Jan 10, 2020 12:31 pm

If all the reactants and products are in the gas phase, do you have to use Kp? Or can you use Kc?

Charysa Santos 4G
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Re: using Kp vs Kc

Postby Charysa Santos 4G » Fri Jan 10, 2020 12:33 pm

If all of the reactants and products are in the gas phase, then you must use Kp if only the partial pressures are given. Kc* is used for concentrations, and is thus used when the reactants and products are in the aqueous phase. I think it depends on what you are given.
Last edited by Charysa Santos 4G on Fri Jan 10, 2020 12:37 pm, edited 1 time in total.

Maia_Jackson_2C
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Re: using Kp vs Kc

Postby Maia_Jackson_2C » Fri Jan 10, 2020 12:35 pm

I think you should get the same number for both, but I'm not entirely sure.

Charysa Santos 4G
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Re: using Kp vs Kc

Postby Charysa Santos 4G » Fri Jan 10, 2020 12:36 pm

*Kc can be used for when concentrations are being used, while Kp is more particular to partial pressures and is more specific to gases.

Katie Kyan 2K
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Re: using Kp vs Kc

Postby Katie Kyan 2K » Fri Jan 10, 2020 4:00 pm

I think for an equation involving gases, either Kp or Kc can be used since you can convert from one to the other using the Ideal Gas Law.

Hannah Pham
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Re: using Kp vs Kc

Postby Hannah Pham » Fri Jan 10, 2020 4:02 pm

Kp is for partial pressure, so when your products and reactants are in the gas phase. Kc is for concentration. However, for gases, you can use either Kc or Kp and just convert using the Ideal Gas Law.

Sally Qiu 2E
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Re: using Kp vs Kc

Postby Sally Qiu 2E » Fri Jan 10, 2020 4:10 pm

you would use Kp if you are given the partial pressures.

Kylie Lim 4G
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Re: using Kp vs Kc

Postby Kylie Lim 4G » Fri Jan 10, 2020 4:29 pm

Kp is used when you have the partial pressures of a gas, and Kc is used for concentration which can be found using PV=nRT

Anna Heckler 2C
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Re: using Kp vs Kc

Postby Anna Heckler 2C » Fri Jan 10, 2020 4:54 pm

You can convert between Kp and Kc using the ideal gas law. Kp is used for partial pressures of gases, whereas Kc is used for concentrations.

lauraxie2e
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Re: using Kp vs Kc

Postby lauraxie2e » Sat Jan 11, 2020 12:54 pm

You use Kp

Jaci Glassick 2G
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Re: using Kp vs Kc

Postby Jaci Glassick 2G » Sat Jan 11, 2020 1:08 pm

Both can be used. Kc can be used when dealing with concentrations while Kp can be used when dealing with partial pressures. I believe the values will be the same.

ayushibanerjee06
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Re: using Kp vs Kc

Postby ayushibanerjee06 » Sat Jan 11, 2020 1:35 pm

You can use both but as everyone else mentioned, make sure to pay attention if you are given atms or mols.

Vivianvelazquez_1J
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Re: using Kp vs Kc

Postby Vivianvelazquez_1J » Sat Jan 11, 2020 2:19 pm

If all the reactants and products are in the gas phase you would use Kp. Kp is for partial pressure when your reactants and products are in the gas phase. While Kc is for when concentrations are being used.

Nuoya Jiang
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Joined: Sat Sep 14, 2019 12:17 am

Re: using Kp vs Kc

Postby Nuoya Jiang » Sat Jan 11, 2020 2:43 pm

In fact, you can use both. Table 5G.2 shows an example of how Kc works for gas reactions.


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