## Calculating K

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Eileen Si 1G
Posts: 120
Joined: Fri Aug 30, 2019 12:17 am

### Calculating K

Is it possible to calculate K for an unbalanced equation? Or can you only calculate Q?

Hope Hyland 2D
Posts: 50
Joined: Wed Feb 20, 2019 12:16 am

### Re: Calculating K

You can only calculate K for equations that are at equilibrium, which is usually indicated in the problem. If the equation is not balanced, then balance it and then find K (assuming the reaction is at equilibrium). Conversely, Q is calculated when the reaction is NOT at equilibrium, and is simply the ratio of products to reactants. You should also balance the equation before calculating Q.

kim 2I
Posts: 105
Joined: Thu Jul 25, 2019 12:17 am

### Re: Calculating K

You should always balance your chemical reactions before doing any sort of calculations so that the molar ratios are accurate. If by unbalanced you're referring to the fact that the reaction hasn't reached equilibrium yet, then the K cannot be calculated since K represents the EQUILIBRIUM constant. Only the reaction quotient can be calculated.

Joanne Lee 1J
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Joined: Thu Jul 25, 2019 12:15 am

### Re: Calculating K

K can only be used when you know that the reaction is at equilibrium. Therefore, if the unbalanced equation is at equilibrium, simply balance the equation and then you can find K.

Jasmine Fendi 1D
Posts: 108
Joined: Sat Aug 24, 2019 12:15 am

### Re: Calculating K

Always balance the equation! When calculating K, the incorrect coefficients will change the exponents in the equation and you would not calculate the correct equilibrium constant

MTanikella_1K
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Joined: Sat Jul 20, 2019 12:16 am

### Re: Calculating K

To calculate Q and K, your equation should be balanced.

Gurmukhi Bevli 4G
Posts: 49
Joined: Wed Nov 14, 2018 12:20 am

### Re: Calculating K

You cannot calculate K for an unbalanced equation, but unless you know the reaction is at equilibrium, you would be calculating Q for a balanced reaction as well. For both the Q and K cases, your reaction still needs to be balanced.

CameronDis2K
Posts: 51
Joined: Wed Feb 20, 2019 12:18 am

### Re: Calculating K

The idea of balancing a reaction is not associated with K; regardless, in order to solve a chemistry problem, the reaction should be balanced (with coefficients). When it is balanced, depending if the information is given for either pressure or concentration of the reactants AND products @ equilibrium, Kc or Kp can be calculated. And the coefficients in the balanced equation is translated to powers: ex. 2NO --> [NO]^2.

Leyna Dang 2H
Posts: 104
Joined: Thu Jul 25, 2019 12:17 am

### Re: Calculating K

Make sure you balance all of your equations. Not doing so could cause you to end up with the wrong K value since your coefficients might be wrong.

Mariah
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Joined: Fri Aug 02, 2019 12:16 am

### Re: Calculating K

Eileen Si 1G wrote:Is it possible to calculate K for an unbalanced equation? Or can you only calculate Q?

An equation must be balanced and at equilibrium to determine K. You must balance the equation before determining either K or Q.

Gabriel Ordonez 2K
Posts: 113
Joined: Sat Jul 20, 2019 12:15 am

### Re: Calculating K

You need to balance the equation because the coefficients will be your concentration exponents in the equilibrium constant. Without the balanced equation, your constant is wrong. Also, without balancing the chemical equation, you are breaking the laws of conservation highlighted in chem 14a.

Gabriel Ordonez 2K
Posts: 113
Joined: Sat Jul 20, 2019 12:15 am

### Re: Calculating K

You need to balance the equation because the coefficients will be your concentration exponents in the equilibrium constant. Without the balanced equation, your constant is wrong. Also, without balancing the chemical equation, you are breaking the laws of conservation highlighted in chem 14a.

sarahartzell1A
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Joined: Fri Sep 28, 2018 12:17 am

### Re: Calculating K

The equation should be balanced.

Jacob Motawakel
Posts: 103
Joined: Wed Sep 18, 2019 12:20 am
Been upvoted: 1 time

### Re: Calculating K

You need balanced equations so you can have the correct coefficients when calculating k. When calculating k the coefficients of the balanced equation become the exponents of the k equation.

005162902
Posts: 102
Joined: Wed Sep 18, 2019 12:15 am

### Re: Calculating K

You should always make sure a chemical reaction is balanced before proceeding to make any calculations. Always.

HuyHa_2H
Posts: 100
Joined: Wed Sep 11, 2019 12:15 am

### Re: Calculating K

The equation has to always be balanced to find both K and Q. The only difference is that K is for when it's at equilibrium whereas Q is not.

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