Inverse Kc  [ENDORSED]


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705512695
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Inverse Kc

Postby 705512695 » Sun Jan 17, 2021 1:10 pm

Hello? When do we know we have to use the inverse of Kc or any K?

Tatyana Bonnet 2H
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Re: Inverse Kc  [ENDORSED]

Postby Tatyana Bonnet 2H » Sun Jan 17, 2021 1:22 pm

Hi! You use the inverse of K when you are looking for the K value of the reverse reaction.
For example:
If you have A--> C+B, and lets say the K value is 3 (this will be the "original" reaction you are looking at)
The reverse reaction C+B--->A will have a K value that is the inverse of the "original" or un-reversed reaction. In this case the K value for the reverse reaction will be 1/3. Hope this helps!

Eliot Kagan 2G
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Re: Inverse Kc

Postby Eliot Kagan 2G » Sun Jan 17, 2021 1:24 pm

You will typically use the inverse Kc when solving for the reverse equation.
For example in the reaction 2SO3 = 2SO2 +O2.
kc will equal ([SO2]^2[02])/[SO3]^2
The inverse kc will equal [SO3]^2/([SO2]^2[02])

ellenulitsky Dis 1I
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Re: Inverse Kc

Postby ellenulitsky Dis 1I » Sun Jan 17, 2021 1:25 pm

How I like to think about it is that if it is aA+bB<---->cC+dD then it is Kc, if it is cC+dD<---->aA+bB then it is 1/Kc (this is the inverse). Hope this helps!

Massimo_Capozza_1G
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Re: Inverse Kc

Postby Massimo_Capozza_1G » Sun Jan 17, 2021 1:42 pm

so the inverse is just reactants over products?

Chudi Onyedika 3A
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Re: Inverse Kc

Postby Chudi Onyedika 3A » Sun Jan 17, 2021 1:52 pm

You would use it when you want the Kc of the reverse reaction.

Ryan Agcaoili 2E
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Re: Inverse Kc

Postby Ryan Agcaoili 2E » Sun Jan 17, 2021 1:57 pm

To state, the inverse of Kc is basically the reciprocal of Kc.

David Y
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Re: Inverse Kc

Postby David Y » Sun Jan 17, 2021 5:07 pm

Inverse of K is used for when finding the reverse reaction.

jasmineculilap_3F
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Re: Inverse Kc

Postby jasmineculilap_3F » Sun Jan 17, 2021 5:12 pm

You want to use the inverse of Kc when solving for the Kc of the reverse reaction.

Justin Zhang_1A
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Re: Inverse Kc

Postby Justin Zhang_1A » Sun Jan 17, 2021 5:25 pm

You'll use the inverse of Kc when you're finding the reverse reaction.

jasonfarrales3D
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Re: Inverse Kc

Postby jasonfarrales3D » Sun Jan 17, 2021 5:27 pm

Hi! We would use the inverse value of K for a reaction when we are trying to find the K value of its reverse reaction.
Last edited by jasonfarrales3D on Sun Jan 17, 2021 7:13 pm, edited 1 time in total.

Zainab Jamali 1H
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Re: Inverse Kc

Postby Zainab Jamali 1H » Sun Jan 17, 2021 5:38 pm

inverse of Kc is to the reverse reaction what Kc is to the forward reaction. that's how I remember it!

Crystal Pan 2G
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Re: Inverse Kc

Postby Crystal Pan 2G » Sun Jan 17, 2021 5:42 pm

Kc is the equilibrium constant, so we use it to describe the forward reaction. When we are describing the reverse reaction(when products are making the reactants), we will use 1/Kc to describe the equilibrium constant. Another two to remember are when we multiply the moles of the entire reaction by two, we will square the equilibrium constant, and when we divide the moles of the entire reaction by two, we will square root the equilibrium constant.

Charisma Arreola 2F
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Re: Inverse Kc

Postby Charisma Arreola 2F » Sun Jan 17, 2021 5:42 pm

The inverse is used when you have a reaction with the correct compounds but the reactant or product is on the wrong side.

Melanie Lin 3E
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Re: Inverse Kc

Postby Melanie Lin 3E » Sun Jan 17, 2021 5:44 pm

Hi! You use inverse Kc (1/Kc) when you want to find the equilibrium constant of the reverse reaction.

Abhinav Behl 3G
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Re: Inverse Kc

Postby Abhinav Behl 3G » Sun Jan 17, 2021 5:51 pm

We would need to find the inverse of Kc (1/Kc) whenever we are asked to find the equilibrium constant of the reverse reaction.

Jared Limqueco 3E
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Re: Inverse Kc

Postby Jared Limqueco 3E » Sun Jan 17, 2021 6:05 pm

So you should be using the inverse for a reverse reaction!

JasmineCap1A
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Re: Inverse Kc

Postby JasmineCap1A » Sun Jan 17, 2021 6:37 pm

Massimo_Capozza_1G wrote:so the inverse is just reactants over products?

To answer your question, yes inverse is reactants over products :)

Jerry_T
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Re: Inverse Kc

Postby Jerry_T » Sun Jan 17, 2021 10:33 pm

Inverse Kc is for the reverse reaction where it's reactants over products.

Ellison Gonzales 1H
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Re: Inverse Kc

Postby Ellison Gonzales 1H » Sun Jan 17, 2021 11:27 pm

Would inverse also be when in some problem solutions they make the products a -x and the reactants a +x in the “change” section of an ICE table? I thought it was almost always that products are positive and reactants are negative but I’ve seen it done both ways now

t_rasul2I
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Re: Inverse Kc

Postby t_rasul2I » Sun Jan 17, 2021 11:32 pm

we inverse kc when we are flipping the reaction or in other words using the reverse reaction. A + B -> C w a k of 2 would have a k of 1/2 if the reaction was flipped and C -> A + B

kristinalaudis3e
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Re: Inverse Kc

Postby kristinalaudis3e » Sun Jan 17, 2021 11:33 pm

if it goes fro A+B--> C then it would be K but if it goes from C-->A+B then it would be 1/K

Geethika Janga 1L
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Re: Inverse Kc

Postby Geethika Janga 1L » Sun Jan 17, 2021 11:35 pm

You simply us reverse Kc or 1/Kc when you are switching from a forward to a reverse reaction. If you want to look at it a different way, we use the reciprocal of Kc with the reverse reaction because the [products] become the [reactants] and visa versa.

Susan Chamling 1F
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Re: Inverse Kc

Postby Susan Chamling 1F » Mon Jan 18, 2021 1:44 am

The inverse K provided the K value of the reverse reaction, but can also be helpful when solving a question that requires combining or manipulating several reactions.

Karen Zheng_2K
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Re: Inverse Kc

Postby Karen Zheng_2K » Mon Jan 18, 2021 8:43 am

Inverse of Kc would just be used for the reverse reaction, so products --> reactants!

emwoodc
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Re: Inverse Kc

Postby emwoodc » Wed Jan 20, 2021 7:51 pm

The inverse Kc is for the inverse reaction ! :)

Taylor K 2D
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Re: Inverse Kc

Postby Taylor K 2D » Wed Jan 20, 2021 7:54 pm

You use the invert of Kc when using the reverse reaction, and you use Kc^n when multiplying the entire equation by the same coefficient.

Chris 1C
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Re: Inverse Kc

Postby Chris 1C » Wed Jan 20, 2021 7:55 pm

Since K is for the forward reaction, we use 1/K for the reverse reaction.

Kiyoka Kim 3C
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Re: Inverse Kc

Postby Kiyoka Kim 3C » Thu Jan 21, 2021 4:42 am

This website https://courses.lumenlearning.com/suny- ... th%20power. has some good explanations!

Andy Hon 3E
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Re: Inverse Kc

Postby Andy Hon 3E » Fri Jan 22, 2021 10:23 pm

Kc is used in the forward reaction and Kc^-1 is used in the inverse reaction.

Brianna Chen 3F
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Re: Inverse Kc

Postby Brianna Chen 3F » Sat Jan 23, 2021 10:57 pm

If you flip an equation, you need to take the inverse of the K value.

Joel Meza 3I
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Re: Inverse Kc

Postby Joel Meza 3I » Sun Jan 24, 2021 1:30 pm

You use the inverse of the K value when you want to find the K value of the reverse reaction. So if you are given K for A+B-->C and you want the K for C-->A+B then you take the inverse of the first K.

Emma Strassner 1J
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Re: Inverse Kc

Postby Emma Strassner 1J » Sun Jan 24, 2021 3:41 pm

You would use the inverse when you are dealing with the reverse reaction.

Isabella Cortes 2H
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Re: Inverse Kc

Postby Isabella Cortes 2H » Sun Jan 24, 2021 3:51 pm

you would use inverse K when you are using the reverse reaction

Presley Gao 2C
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Re: Inverse Kc

Postby Presley Gao 2C » Sun Jan 24, 2021 4:16 pm

We have to use the inverse of Kc or any K when we are considering the reverse reaction.

Javier Perez M 1H
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Re: Inverse Kc

Postby Javier Perez M 1H » Sun Jan 31, 2021 11:37 pm

Remember that in reverse, so do your moles of products and reactants flip.

Mansi Solanki 3A
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Re: Inverse Kc

Postby Mansi Solanki 3A » Sun Jan 31, 2021 11:39 pm

You would use the inverse of Kc when you are looking at the reverse reaction taking place since now the reactants would be in the numerator and the products would be in the denominator.

Sam Wentzel 1F 14B
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Re: Inverse Kc

Postby Sam Wentzel 1F 14B » Sun Jan 31, 2021 11:39 pm

Use the inverse for the reverse reaction!

Daniel Hernandez 1G
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Re: Inverse Kc

Postby Daniel Hernandez 1G » Sun Jan 31, 2021 11:44 pm

You would use the inverse of Kc when you are asked to find the equilibrium of the reverse reaction.

LovepreetSran_3H
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Re: Inverse Kc

Postby LovepreetSran_3H » Sun Jan 31, 2021 11:46 pm

You would use it when you want the Kc of the reverse reaction

Mehreen 3I
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Re: Inverse Kc

Postby Mehreen 3I » Sun Jan 31, 2021 11:46 pm

You would only use the inverse of K when you want to find the Kc of the reverse reaction.

MariaCassol1L
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Re: Inverse Kc

Postby MariaCassol1L » Tue Feb 02, 2021 9:05 pm

You use 1/Kc when you are looking at the Kc of a reverse reaction. So for example, if they give you Kc=3 for 2C+O2--->2CO @ a given temperature, then 2CO---> 2C+O2 will have a Kc=1/3 at that same temperature.


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