## K vs Kp vs Kc

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KNguyen_1I
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Joined: Sat Aug 17, 2019 12:16 am

### K vs Kp vs Kc

What it says on the tin ^

Jordan Young 2J
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### Re: K vs Kp vs Kc

K is general term for the equilibrium constant of products over reactants. Kp means that the values in the equilibrium constant are the partial pressures of usually gases. Kc means that the values in the equilibrium constant are concentrations of aqueous solutions

WYacob_2C
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### Re: K vs Kp vs Kc

If in a reaction, all species are in the gas phase, typically you would use their partial pressures, meaning you would use Kp. If the species in a reaction are aqueous, you would use the concentrations and Kc.

Verity Lai 2K
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### Re: K vs Kp vs Kc

They generally all mean the same thing, they are the equilibrium constants. The p or c denotes if it is based on partial pressure or the concentration of reactants and products.

LBacker_2E
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### Re: K vs Kp vs Kc

If the question just asks for K, you can choose between Kc and Kp by looking at other information in the problem. If dealing with aqueous solutions you should probably find Kc, but if dealing with gaseous solutions, it might be better to calculate Kp. This seems to be the general trend, but may not always be the case.

805097738
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### Re: K vs Kp vs Kc

K is the general term for equilibrium constant. Kp is for reaction involving gases and Kc is for reactions involving aqueous.

Michellekim1H
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### Re: K vs Kp vs Kc

Kp is only used for partial pressure(for gases) whereas Kc is just the equilibrium constant regarding molar concentrations.

Madeline Phan 1E
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### Re: K vs Kp vs Kc

when writing the expression for k, how do you know when to use brackets or to write p in front?

KNguyen_1I
Posts: 101
Joined: Sat Aug 17, 2019 12:16 am

### Re: K vs Kp vs Kc

Madeline Phan 1J wrote:when writing the expression for k, how do you know when to use brackets or to write p in front?

I know that P is for partial pressure and brackets are used for concentration so Kc.

Hailey Kim 4G
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### Re: K vs Kp vs Kc

Madeline Phan 1J wrote:when writing the expression for k, how do you know when to use brackets or to write p in front?

You use brackets to represent concentration and you use P to represent partial pressure. For a gas, we use its partial pressure and the equilibrium constant is denoted by Kp.

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