Qc vs Kc

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Bryce Ramirez 1J
Posts: 120
Joined: Sat Aug 24, 2019 12:16 am

Qc vs Kc

Postby Bryce Ramirez 1J » Sat Mar 14, 2020 8:30 pm

What are the rules for when Qc is greater than Kc and when Qc is less than Kc? And what happens when the two are exactly equal?

Indy Bui 1l
Posts: 99
Joined: Sat Sep 07, 2019 12:19 am

Re: Qc vs Kc

Postby Indy Bui 1l » Sat Mar 14, 2020 8:33 pm

If they are equal then the reaction is at equilibrium. If Q>K then the forward reaction or products are favored. The opposite is true for Q<K the reactants are favored.

Jared_Yuge
Posts: 100
Joined: Sat Aug 17, 2019 12:17 am

Re: Qc vs Kc

Postby Jared_Yuge » Sat Mar 14, 2020 8:33 pm

Q will tend to go towards Kc, so when Q >Kc it will shift towards the reactants and when Q<Kc it will shift towards the products.

chimerila
Posts: 53
Joined: Wed Nov 14, 2018 12:23 am

Re: Qc vs Kc

Postby chimerila » Sat Mar 14, 2020 8:34 pm

Q > K, system shifts left
Q < K, system shifts right
Q = K, system is at equilibrium, no shift in either direction

Jared_Yuge
Posts: 100
Joined: Sat Aug 17, 2019 12:17 am

Re: Qc vs Kc

Postby Jared_Yuge » Sat Mar 14, 2020 8:35 pm

When Q and Kc are equal then the reaction has reached equilibrium and Q will stay the same. This doesn't mean that the reaction is no longer occurring rather that both the forward reaction and the reverse reaction are happening at the same rate

Jacey Yang 1F
Posts: 101
Joined: Fri Aug 09, 2019 12:17 am

Re: Qc vs Kc

Postby Jacey Yang 1F » Sat Mar 14, 2020 8:36 pm

If Q>K, then the products are greater and the reverse reaction is favored. If Q<K, then reactants are greater and the forward reaction is favored.

Frank He 4G
Posts: 50
Joined: Tue Nov 12, 2019 12:19 am

Re: Qc vs Kc

Postby Frank He 4G » Sat Mar 14, 2020 8:50 pm

Since Q is calculated similarly, when Q is higher than K, we know that there are more products than reactants at Q. If there are more products than at equilibrium, then the reaction has to be proceeding in reverse to go to equilibrium. And the reverse is also true.

Adriana_4F
Posts: 74
Joined: Fri Sep 28, 2018 12:29 am

Re: Qc vs Kc

Postby Adriana_4F » Sat Mar 14, 2020 8:56 pm

Q > K ----> Reactants are favored
Q < K -----> Products favored
Q = K -----> Equilibrium

Think about the concentration of reactants and products: When Q > K, the concentration (or activities) of products increase (numerator increases) causing the rxn to make more reactants

Gurmukhi Bevli 4G
Posts: 49
Joined: Wed Nov 14, 2018 12:20 am

Re: Qc vs Kc

Postby Gurmukhi Bevli 4G » Wed Mar 18, 2020 1:20 am

For Q=K, the reaction is at equilibrium
For Q>K, the forward reaction is favored (towards the products)
For Q<K, the reverse reaction is favored (towards the reactants)


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