Value of Q
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Value of Q
When looking at the equation w(max)= , I was confused as to what Q is? I understand it is the reaction quotient but how exactly do you calculate that?
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Re: Value of Q
You calculate Q in a similar way to the equilibrium constant! It is the concentration of the products raised to their coefficient divided by the reactants raised to their coefficients. the only difference is for Q, the reaction is not at equilibrium.
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Re: Value of Q
As Katie said! Also, if Q<K, reaction will continue to shift towards products, if Q>K, reaction will shift towards reactants.
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Re: Value of Q
Q would represent which direction the equation shifts and it is not at equilibrium, as opposed to K.
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Re: Value of Q
Q is calculated the same way as the equilibrium constant K. So we can figure this out by taking the Q=[products]/[reactants]. If Q=K then the system is at equilibrium.
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Re: Value of Q
Q is the quotient reactant that we learned for and before Midterm 1! It is [P]/[R] like K but NOT at equilibrium.
To compare Q and K use le chatelier's princple:
Q<K; will shift to products so -DeltaG and spontaneous
Q=K; equilibrium
Q>K; will shift to reactants so +DeltaG and spontaneous in the reverse rxn
To compare Q and K use le chatelier's princple:
Q<K; will shift to products so -DeltaG and spontaneous
Q=K; equilibrium
Q>K; will shift to reactants so +DeltaG and spontaneous in the reverse rxn
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Re: Value of Q
Q is the ratio of concentrations of the products over the reactants with respect to their stoichiometric coefficients.
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Re: Value of Q
Hi! The value of Q is the reaction quotient, which can be solved the same as you calculate K (the equilibrium constant).
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Re: Value of Q
Q is the same thing as K, only that the reaction has not reached equilibrium. The problem should give the values of the concentrations for the products and reactants, so you can calculate Q knowing the balanced equation. Depending on the value of Q, the value of the Gibbs free energy will determine if more products or more reactants need to be formed to reach K.
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Re: Value of Q
You calculate Q in the same way you calculate K; it is the concentration of the products, to the power of their stoichiometric coefficient, over the concentration of the reactants to their stoichiometric coefficients.
Re: Value of Q
Concentration of products (to the power of their coefficients) over concentrations of reactants (to the power of their coefficients), or I think you can do the same with partial pressures. It's the same as calculating the equilibrium constant the system's just not at equilibrium
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Re: Value of Q
Q is simply the reaction quotient from the chemical equillibrium unit. It is the ratio of concentrations of products to reactants which is calculated from (concentration of product)^n x (concentration of product 2)^n etc. divided by (concentration of reactant)^n x (concentration of reactant 2)^n. Where n is the number of moles of the corresponding species
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Re: Value of Q
Q is what we call K or the equilibrium but Q is K but not at equilibrium and its used to identify which way the reaction will proceed.
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Re: Value of Q
Q is calculated the same way that we find K. It is the concentration of products over the concentration of reactants both raised to the power of their stoichiometric coefficients when a reaction is not at equilibrium.
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Re: Value of Q
Q is the equilibrium constant. If you have molar concentrations of the reactants and products you can make it reactants/products and put them to the power of number of moles. That gives you the Q value.
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Re: Value of Q
Finding the value of Q is the same as finding the equilibrium constant K. We divide the partial pressure or the molar concentrations with the products on top and the reactants on the bottom with the coefficients as exponents.
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Re: Value of Q
Calculating Q, the reaction quotient, is the same process as calculating K, the equilibrium constant, which we learned earlier. You can do this by taking the concentrations/partial pressures of the products and raising each one to their stoichiometric coefficients and dividing that by the concentrations/partial pressures of the reactants raised to each of their stoichiometric coefficients. You are usually given the values of the concentrations/partial pressures.
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Re: Value of Q
Q is the same concept as K but Q is not at equilibrium and it's used to determine which way the reaction will proceed.
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Re: Value of Q
How do you know to use the equation with Q instead of K based off the question? If the question is asking you to compare something to a K value, is that when we use this equation with the Q?
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