equilibrium constant purpose

[Mallika Singh 1G]

What exactly does K tell us about a reaction?

[lilymayek_1E]

K is a summary of the composition of a reactant mixture at equilibrium essentially; it's a value that represents where reactants and products have no net change during the reaction, and this state is represented by K (which is essentially a ratio value between reactants and products).

[Adam Kramer 1A]

K will tell the proportion of concentrations needed between products and reactants in a reaction at equilibrium, or in the case of Kp, the partial pressures that will allow the reaction to be at equilibrium.

[Michelle N - 2C]

From what I know, K basically tells us that there's a certain ratio needed from the concentrations of products and from the concentrations of reactants so that it could reach equilibrium. With a certain amount available within the solution, there has will be both forward and reverse rates occurring (R to P and P to R). Once those two rates become constant, they have reached equilibrium, and thus, K.

Once you know K, you can have all sorts of different reaction vessels with different initial concentrations, yet they should all come together with the same K value.

[Marni Kahn 1A]

K is also important because if given K and initial concentrations of one or more reactants, you can use that K value to find the composition of the mixture at equilibrium.

[Amy Pham 1D]

From an experimental standpoint, knowing the K of a reaction would allow us to determine when an reaction has reached equilibrium. With the knowledge of K, you could measure the concentrations/partial pressures of the reactants and products in the reaction and use them to calculate a value of Q. You could then compare Q to K, and if they are the same, then you know that your reaction has reached equilibrium.

[Justin Quan 4I]

The equilibrium constant K tells you the ratio of products to reactants. If K is a large number, it means that the equilibrium concentration of the products is large. Comparing K to Q will also help you decide which direction the reaction will proceed.

[Mariah]

It helps us to know the ratio of products and reactants when a rx is at equilibrium.