Constant K and reaction quotient

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Mike Vinci 2B
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Constant K and reaction quotient

Postby Mike Vinci 2B » Sun Feb 04, 2018 11:37 pm

Hi all,
Could someone elaborate on the difference between the equilibrium constant, K, and the reaction quotient, Q? Also, if you could remind me of what it means if Q>K, Q=K, and so on in terms of the chemical reaction, and if these concepts are important for the subject we're studying now.

Mitch Mologne 1A
Posts: 74
Joined: Fri Sep 29, 2017 7:04 am

Re: Constant K and reaction quotient

Postby Mitch Mologne 1A » Sun Feb 04, 2018 11:40 pm

So if Q=K, then a system is at equilibrium. If Q>K, then the system will favor the reverse because that means there is too much product (higher the value the more it favors the products. If Q<K, then the system will favor the forward reaction.

Tasnia Haider 1E
Posts: 55
Joined: Sat Jul 22, 2017 3:01 am

Re: Constant K and reaction quotient

Postby Tasnia Haider 1E » Sun Feb 04, 2018 11:40 pm

K is supposed to symbolize when the reaction is at equilibrium. The reactant quotient is when the reaction is not at equilibrium. When Q>K, that means there is too much product which means the reverse reaction is favored. When Q<K, that means there is too much reactant which means the forward reaction is favored.

Jiun Yue Chung 2I
Posts: 27
Joined: Fri Sep 29, 2017 7:06 am

Re: Constant K and reaction quotient

Postby Jiun Yue Chung 2I » Mon Feb 05, 2018 12:46 am

To add, K, the equilibirum constant determines the relative concentrations (and partial pressures) of the products and reactants of the reaction at equilibrium while the Q, or reaction quotient says the same thing but when the reaction is not at equilibrium. A large K indicates that the concentration of products is large and the opposite would be that the concentration is larger for reactants with a small K value.


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