## K and Q

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Andy_Yousif_1A
Posts: 10
Joined: Wed Sep 21, 2016 2:59 pm

### K and Q

Why is Q not equal to K if they have the same formula?

Christian Hardoy 3F
Posts: 41
Joined: Fri Jul 15, 2016 3:00 am

### Re: K and Q

Q can be greater than, equal to, or less than K. Q is the reaction quotient and can be calculated at any point during a reaction. It has the same formula as K because it is used to determine if an equation is at equilibrium at a certain point during a reaction. Remember that the "formula" for K and Q gives you a ratio of products to reactants. K is the ratio when the reaction is at equilibrium. If Q is larger than K, it means that the numerator in the equation is larger than the numerator when the reaction is at equilibrium, meaning that the current amount of products is too large, relative to the amount of reactants. When Q > K, the reaction will proceed to the left, as the reaction moves back towards the equilibrium ratio. When Q < K, the numerator is smaller than the numerator when the reaction is at equilibrium, meaning that the current amount of products is too small, relative to the amount of reactants. In this case, the reaction will proceed to the right, as the reaction moves back towards the equilibrium ratio. When the system is at equilibrium, Q will equal K.