K vs P

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Agustina Santa Cruz 2F
Posts: 88
Joined: Wed Sep 30, 2020 10:01 pm

K vs P

Postby Agustina Santa Cruz 2F » Sun Jan 10, 2021 7:57 pm

When should you calculate P instead of K? I initially thought P was only for gases but then I think I saw K be calculated for a homogenous gas reaction.

Seraphina Joseph 1C
Posts: 97
Joined: Wed Sep 30, 2020 9:31 pm

Re: K vs P

Postby Seraphina Joseph 1C » Sun Jan 10, 2021 8:00 pm

Do you mean P meaning pressure or P meaning products?

AndrewNguyen_2H
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Joined: Wed Sep 30, 2020 9:59 pm

Re: K vs P

Postby AndrewNguyen_2H » Sun Jan 10, 2021 8:02 pm

A reaction with solely gases can use Kc or Kp. You can convert between the two using the ideal gas equation.

Izamary Marquez 2H
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Joined: Wed Sep 30, 2020 9:44 pm

Re: K vs P

Postby Izamary Marquez 2H » Sun Jan 10, 2021 8:11 pm

Also, can someone explain how the relationship Q>P means products are favored (I understand it's because the numerator is higher) but I am confused on how this tells us the direction of the reaction and what it really means regarding the stability of the reaction. If someone could explain the correlation that would be extremely helpful!

Charlotte Chen 3B
Posts: 38
Joined: Wed Nov 18, 2020 12:29 am

Re: K vs P

Postby Charlotte Chen 3B » Sun Jan 10, 2021 8:26 pm

Izamary Marquez 2H wrote:Also, can someone explain how the relationship Q>P means products are favored (I understand it's because the numerator is higher) but I am confused on how this tells us the direction of the reaction and what it really means regarding the stability of the reaction. If someone could explain the correlation that would be extremely helpful!


When Q>K, that means there are more products than reactants present, so the reaction (system) will shift to the left to decrease the amount of products, and produce more reactants. In general, a system in equilibrium will shift (re–distribute the relative amounts of reactants and products) when it is disturbed in order to counter the change

Kiara Phillips 3L
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Joined: Wed Sep 30, 2020 10:04 pm

Re: K vs P

Postby Kiara Phillips 3L » Sun Jan 10, 2021 9:09 pm

Kc vs Kp Fro my understanding they both have to do with the equilibrium constant it is just that Kp is when you are dealing with pressure and gas and Kc is everything that does not fit into that category.

Anastasia Yulo 1C
Posts: 84
Joined: Wed Sep 30, 2020 9:47 pm

Re: K vs P

Postby Anastasia Yulo 1C » Sun Jan 10, 2021 9:54 pm

Kc is the equilibrium quotient which takes into account concentration. Kp is the equilibrium quotient which takes into account pressure. Given partial pressures, concentration can be solved using PV=nRT.


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