### change in Kc

Posted:

**Wed Feb 12, 2020 12:10 pm**when there is a constant multiplied to the overall chemical equation, how does Kc change? what are the rules for Kc when there is a change to the overall reaction(s)?

Created by Dr. Laurence Lavelle

https://lavelle.chem.ucla.edu/forum/

https://lavelle.chem.ucla.edu/forum/viewtopic.php?f=49&t=59271

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Posted: **Wed Feb 12, 2020 12:10 pm**

when there is a constant multiplied to the overall chemical equation, how does Kc change? what are the rules for Kc when there is a change to the overall reaction(s)?

Posted: **Wed Feb 12, 2020 12:15 pm**

you raise Kc to whatever you multiply by. if you multiply by 2 then Kc = Kc^2, if you divide by 2 / multiply by 1/2 then Kc = Kc^1/2 or square root of Kc.

Posted: **Thu Feb 13, 2020 1:24 am**

I agree with the previous response. If you think about it, it makes sense because you're changing the coefficient of each reactant/product by the same factor, and the coefficients determine what power the values are raised to. For example, if the overall reaction is multiplied by 2, then each reactant/product in K is raised to the power of 2, and K overall would be raised to the power of 2.

Posted: **Thu Feb 13, 2020 2:38 am**

If you reverse the reaction, then Kc becomes 1/Kc. If you multiply the reaction by a constant, Kc equals Kc^x, where x is that constant.

Posted: **Thu Feb 13, 2020 8:42 am**

Multiplying a reaction by some constant is the mathematical equivalent of raising the power of the Kc of said reaction to that same constant.

Posted: **Thu Feb 13, 2020 9:23 am**

If you were to reverse a reaction, the value for the constant will be the inverse (1/Kc) whereas if you multiply the reaction by some constant, the value of Kc will have to be raised by the same value (Kc^x).