K vs. Q
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K vs. Q
Hi! Just to clarify, Q and K are both the ratio of products over reactants, the only difference is that Q is used when the reaction is not at equilibrium? Thanks!
Re: K vs. Q
Hello Lilly!
The time when we would use the reaction quotient (Q) would be any time during the reaction and like you stated, the K constant is used for when at an equilibrium! Hope this helps!
The time when we would use the reaction quotient (Q) would be any time during the reaction and like you stated, the K constant is used for when at an equilibrium! Hope this helps!
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Re: K vs. Q
Exactly! Q is just [P]/[R] at any given time. When Q = K, then we say the reaction is at equilibrium.
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Re: K vs. Q
Yup! They are both calculated the same way, and Q is used as a way to compare the state of the system and whether what direction the reaction is going relative to the value of K.
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Re: K vs. Q
Q could be used at anytime of a reaction that is happening, it is just the ratio of products to reactants. However, K shall only be used when the reaction reaches equilibrium.
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Re: K vs. Q
You are exactly right. Q=[P]/[R] but can be used even if the system is not in equilibrium.
Some important things to keep in mind regarding Q and K:
Q=K at equilibrium.
If Q<K, the reaction will go forward/towards products.
If Q>K, the reaction will go backward/towards reactants.
Some important things to keep in mind regarding Q and K:
Q=K at equilibrium.
If Q<K, the reaction will go forward/towards products.
If Q>K, the reaction will go backward/towards reactants.
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Re: K vs. Q
Yes, Q is used anytime the reaction is not in equilibrium and K is only used when the reaction is in equilibrium. You can use the Q value to comparatively to the K value, to see where you are in the reaction (to see if it needs to shift right or left).
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Re: K vs. Q
They are calculated the same way, however when calculating K the concentrations of product and reactants must be those at which the reaction is at equilibrium, whereas the concentrations of products and reactants used to calculate Q can be from any given point at which the reaction is occurring.
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Re: K vs. Q
Yes, that is correct. Q is the reaction quotient and K is the equilibrium constant. We use Q to figure out which direction a reaction will shift to reach equilibrium. If K > Q, the forward reaction is favored, converting reactants into products. If K < Q, the reverse reaction is favored, converting products into reactants. If K = Q, we know the system is at equilibrium and neither the forward nor reverse reaction is favored; instead they proceed at equal rates.
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Re: K vs. Q
Yes, Q just applies to a reaction that is not at equilibrium, while K is at equilibrium. You can compare the two values to determine which direction the reaction is going.
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Re: K vs. Q
Yes, Q is the reaction quotinent. Use Q when the reaction is not at equilibrium and use K when the reaction is at equilibrium.
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Re: K vs. Q
Q is the reaction quotient of the reaction and can be used to analyze the state of the system. It is important to note both Q and K are calculated with the same formula, but when calculating Q we do not know the state of the system necessarily. If Q>K then the reverse reaction is favored, and if Q<K then the forward reaction is favored. If Q=K, which is rare, then we can say the reaction is at equilibrium.
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Re: K vs. Q
K is used only when the reaction is at equilibrium. Q is used when we are unsure whether or not the reaction is at equilibrium. Although Q can be equal to K (meaning the reaction at that point is at equilibrium), Q can also be greater than or equal to K. K is a constant, whereas Q is not.
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Re: K vs. Q
So if we are given Kc and then are told to calculate Q with the given concentrations of the products and reactants, Q would tell us if the reaction is at equilibrium or if the reaction leans toward the products/reactants?
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Re: K vs. Q
keely_bales_1f wrote:So if we are given Kc and then are told to calculate Q with the given concentrations of the products and reactants, Q would tell us if the reaction is at equilibrium or if the reaction leans toward the products/reactants?
Yup, that's right!
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Re: K vs. Q
Q is a quantity that changes as a reaction system approaches equilibrium. (have not yet reached equilibrium; reaction in progress)
K is the numerical value of Q at the "end" of the reaction when equilibrium is reached.
K is the numerical value of Q at the "end" of the reaction when equilibrium is reached.
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Re: K vs. Q
Yes! Q is used when the system hasn't reach equilibrium yet while K is used when the system has reach equilibrium.
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Re: K vs. Q
Yes Q is used at any time to see where the reaction is at in relation to equilibrium and K is the constant value at equilibrium. If Q=K then it is at equilibrium.
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Re: K vs. Q
Yes, Q and K are both the ratio of [products]/ [reactants] and the only difference is that K is used when equilibrium has been reached and Q is used anytime the reaction is occurring.
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Re: K vs. Q
Hi Lilly! You are correct. The reaction quotient, Q, is used to represent the concentration/partial pressure of products divided by the concentration/partial pressure of reactants of the reaction at ANY time. The equilibrium constant, K, represents the reaction at equilibrium.
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Re: K vs. Q
Correct. Product divided by reactants will determine the K. If reaction is not at equilibrium, Q can be determined in order to identify if the reactant or products will be favored.
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Re: K vs. Q
Hi! You're correct! K is when the system is at equilibrium and Q is when the system is not, so if Q=K then the system has reached equilibrium.
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Re: K vs. Q
Yes, that's correct, Q is just the ratio at any time during the reaction and K (equilibrium constant) is the ratio when the reaction is at equilibrium.
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Re: K vs. Q
Yep you're right Q is when the reaction is not at equilibrium and K is when it is at equilibrium, but it is the same calculation.
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Re: K vs. Q
Yes, Q and K are both the same process of using the ratio of products to reactants. The only difference is that Q is when the reaction is not at equilibrium.
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Re: K vs. Q
Yes you are correct. Q is used when they are not equilibrium values yet. You can find Q at any time during the reaction but K is only when the reaction is at equilibrium.
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Re: K vs. Q
Yes, you are correct! Q is found the same way as K and you use Q when the reaction has not reached equilibrium.
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Re: K vs. Q
Yes, both Q and K are calculated using the same method. The only difference is that K is the ratio of concentrations when the system is at equilibrium. Q is the ratio of concentrations when the system isn't at equilibrium.
Re: K vs. Q
K is used when a reaction is at equilibrium and Q is used when an equation is not over equilibrium. They are both always Products/Reactants
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Re: K vs. Q
Yes! Just to clarify even more, Q is the reaction quotient while K is the equilibrium constant!
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Re: K vs. Q
Q and K are both calculated using the [p]/[r]. Q is the reaction quotient, and is used at any time where the reaction is not at equilibrium. K is for when the reaction is at equilibrium.
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Re: K vs. Q
You're correct! I believe Q can be calculated at any time during the reaction (including at equilibrium) but if it is specified that the reaction is at equilibrium you can use K instead.
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Re: K vs. Q
You're right! The K is used for the system when it is in equilibrium while Q can be used at any point in time for the system.
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Re: K vs. Q
Yep, Q is just the expression anytime during the expression wheres as K is the value for when it is in equilibrium.
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Re: K vs. Q
Correct. Whenever you take the ratio of the concentration (or partial pressure) of products over reactants when it is not at equilibrium, you are solving for Q, the reaction quotient. If the reaction is at equilibrium, then the ratio of products to reactants is the equilibrium constant, K.
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Re: K vs. Q
Q represents products/reactants in general, while K only represents products/reactants at equilibrium.
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Re: K vs. Q
They are both calculated the same way however Q reflects the state of the reaction whereas K represents the reaction at equilibrium.
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Re: K vs. Q
Yes Q and K are essentially the same thing. The only difference is that K is the concentration of products and reactants when it is at equilibrium and Q is at any time during the reaction. Q's value relative to K can be used to determine the direction that the reaction is tending towards.
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Re: K vs. Q
Q and K are found the exact same way with the ratio of products/reactants, but K is just specifically referring to the value when the reaction reaches equilibrium.
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Re: K vs. Q
Just to clarify, will we always be able to assume that the reaction is at equilibrium when K=Q? Thanks!!
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Re: K vs. Q
Lilly Catarozoli 1B wrote:Hi! Just to clarify, Q and K are both the ratio of products over reactants, the only difference is that Q is used when the reaction is not at equilibrium? Thanks!
Yes, exactly! The Q is known as the reaction quotient and it is used when the reaction is not at equilibrium (all other times).
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Re: K vs. Q
They are both calculated using the same method ([P]/[R]), but Q represents the reaction at any time while K represents the reaction at equilibrium.
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Re: K vs. Q
Devan Nathu - 2H wrote:Just to clarify, will we always be able to assume that the reaction is at equilibrium when K=Q? Thanks!!
Yes, since K is the equilibrium constant, when Q (the reaction quotient) is equal to K, the reaction is at equilibrium.
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Re: K vs. Q
Q is P/R at any time during the reaction and we can use it to determine which reaction is favored.
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