Understanding Q

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Cecilia Jardon 1I
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Joined: Thu Sep 27, 2018 11:16 pm

Understanding Q

Postby Cecilia Jardon 1I » Fri Jan 18, 2019 6:47 pm

Just to clarify, Q is the same chemical reaction but just in the state where it has not yet reached equilibrium?

MaanasO 1A
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Joined: Thu Sep 27, 2018 11:26 pm

Re: Understanding Q

Postby MaanasO 1A » Fri Jan 18, 2019 7:10 pm

Hi Cecilia!

So Q and K are calculated in the same way but with different concentrations. Think of K as the Q when the reaction is at equilibrium.

Hope that helps!

Casandra
Posts: 50
Joined: Thu Sep 27, 2018 11:17 pm

Re: Understanding Q

Postby Casandra » Fri Jan 18, 2019 7:16 pm

Q alone tells you nothing, but once compared to K, it tells you where the reaction is in terms of reaching the equilibrium concentration.

Cade Okohira 4K
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Joined: Thu Sep 27, 2018 11:15 pm

Re: Understanding Q

Postby Cade Okohira 4K » Sat Jan 19, 2019 1:57 am

You find Q and K in the same way, by dividing the concentrations of the products by the concentrations of the reactants. However, K is the equilibrium constant, while Q is the reaction quotient, which is the constant of the equation at any time. Q can then be compared to K to find out whether the equation is shifting to the left or right (or favoring the reactants or products).

Dayna Pham 1I
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Re: Understanding Q

Postby Dayna Pham 1I » Sat Jan 19, 2019 2:23 am

Adding onto what they all said, I’d like to relate this to Le Chatelier’s Principle. When pressure/volume/concentration change, it is Q that changes, not K. However, when temperature changes, then K changes.

005113695
Posts: 45
Joined: Thu Sep 27, 2018 11:15 pm

Re: Understanding Q

Postby 005113695 » Sat Jan 19, 2019 3:11 am

Hi!
Q is calculated the same way as K, but instead of being the equilibrium concentration, it can tell you which way the reaction is proceeding.

MichaelMoreno2G
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Joined: Thu Sep 27, 2018 11:26 pm

Re: Understanding Q

Postby MichaelMoreno2G » Sat Jan 19, 2019 10:24 am

Can someone clarify what the significance of Q<K is and vice-versa?

Karishma_1G
Posts: 46
Joined: Thu Sep 27, 2018 11:18 pm

Re: Understanding Q

Postby Karishma_1G » Sat Jan 19, 2019 12:32 pm

K>Q and K<Q is significant because it helps us understand whether the reaction has reached equilibrium or not. Since Q (the reaction quotient) is calculated at a specific time during the span of a reaction, by comparing it to K we can see if the reaction has to form more products or reactants to reach equilibrium. If K>Q, the reaction will proceed to the products. If K<Q, the reaction will proceed to the reactants.

Simmi Diwanji 2B
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Joined: Thu Sep 27, 2018 11:20 pm

Re: Understanding Q

Postby Simmi Diwanji 2B » Sun Jan 20, 2019 3:38 pm

The significance of Q<K and vice versa is that it helps determine whether a reaction has reached equilibrium at a certain point in time. If it hasn't reached equilibrium (Q=K), than that means that the reaction will either favor the reactants or products in order to proceed towards equilibrium.

Sapna Ramappa 1J
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Joined: Thu Sep 27, 2018 11:24 pm

Re: Understanding Q

Postby Sapna Ramappa 1J » Sun Jan 20, 2019 4:21 pm

Comparing Q and K allows us to see whether or not the system is at equilibrium. If Q=K, then the system is at equilibrium. Otherwise, we can see if Q>K or if K>Q to determine whether the reaction favors the reactants or the products.


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