Concentrations

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Jorja De Jesus 2C
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Concentrations

Postby Jorja De Jesus 2C » Sat Jan 18, 2020 11:48 pm

When is concentration the only thing that affects K and when is it not the only thing?

Lara Kristine Bacasen 1L
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Re: Concentrations

Postby Lara Kristine Bacasen 1L » Sun Jan 19, 2020 12:09 am

I'm not sure if this answers your question but if the temperature is the same the concentration does not change the equilibrium constant (k). However, if you change the temperature it does change the equilibrium constant.

Kayla Maldonado 1C
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Re: Concentrations

Postby Kayla Maldonado 1C » Sun Jan 19, 2020 12:20 am

Lara Kristine Bacasen 1L wrote:I'm not sure if this answers your question but if the temperature is the same the concentration does not change the equilibrium constant (k). However, if you change the temperature it does change the equilibrium constant.

So temperature is the only thing that can affect the the equilibrium constant ?

Lara Kristine Bacasen 1L
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Re: Concentrations

Postby Lara Kristine Bacasen 1L » Sun Jan 19, 2020 2:53 pm

Kayla Maldonado 1A wrote:
Lara Kristine Bacasen 1L wrote:I'm not sure if this answers your question but if the temperature is the same the concentration does not change the equilibrium constant (k). However, if you change the temperature it does change the equilibrium constant.

So temperature is the only thing that can affect the the equilibrium constant ?

Yes, I believe so. If you change the concentration of something in the mixture, the position of equilibrium moves in. Like from favoring products or the reactants. This happens to fix the change that was made but the K doesn't change.

Matt F
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Re: Concentrations

Postby Matt F » Sun Jan 19, 2020 3:29 pm

Changing the concentration or pressure can cause the equilibrium to "favor" the products or reactants, but in both cases the equilibrium constant K will stay the same. Only when temperature is changed is K changed because of a permanent change in the system's dynamics (depending on if it's endothermic or exothermic)

Rory Simpson 2F
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Re: Concentrations

Postby Rory Simpson 2F » Sun Jan 19, 2020 3:31 pm

Concentration and pressure only affects Q and not K; the reaction will shift accordingly to return to a ratio of reactants and products equal to K. Temperature actually changes K because of the changes in energy that are involved in the reaction.

Anokhi Patel 2B
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Re: Concentrations

Postby Anokhi Patel 2B » Sun Jan 19, 2020 3:45 pm

K is only affected by the concentration when measuring Kc instead of the K for partial pressure Kp.

Cavalli_1H
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Re: Concentrations

Postby Cavalli_1H » Sun Jan 19, 2020 3:58 pm

concentration only affects K when you are working with Kc (involving aqueous solutions)

Jocelyn Thorp 1A
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Re: Concentrations

Postby Jocelyn Thorp 1A » Sun Jan 19, 2020 4:22 pm

Matt F wrote:Changing the concentration or pressure can cause the equilibrium to "favor" the products or reactants, but in both cases the equilibrium constant K will stay the same. Only when temperature is changed is K changed because of a permanent change in the system's dynamics (depending on if it's endothermic or exothermic)


Adding on to this:

If the reaction is exothermic, adding heat will make k go down; cooling will make k go up.
If the reaction is endothermic, adding heat will make k increase; cooling will make k decrease.

Veronica Lu 2H
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Re: Concentrations

Postby Veronica Lu 2H » Sun Jan 19, 2020 6:28 pm

the concentration only affects the Kc not Kp

Sreyes_1C
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Re: Concentrations

Postby Sreyes_1C » Sun Jan 19, 2020 6:41 pm

Kayla Maldonado 1A wrote:
Lara Kristine Bacasen 1L wrote:I'm not sure if this answers your question but if the temperature is the same the concentration does not change the equilibrium constant (k). However, if you change the temperature it does change the equilibrium constant.

So temperature is the only thing that can affect the the equilibrium constant ?


Yes I believe temperature is the only thing that can affect it

TimVintsDis4L
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Re: Concentrations

Postby TimVintsDis4L » Sun Jan 19, 2020 6:44 pm

Temperature is the only thing that affects the constant because even if the concentration changes, the equation will do its best to mitigate the change. Le Chatelier's Principle pretty much explains this.

005324438
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Re: Concentrations

Postby 005324438 » Sun Jan 19, 2020 7:02 pm

Concentrations don't effect the K value in itself, but can effect the direction of the reaction. Only temperature can change the K value.


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