How is the reaction quotient used to determine whether a system is at equilibrium?

The answer to the question above is explained below

Explanation:

The reaction quotient, Q, is a measure of the relative amounts of reactants and products during a chemical reaction as it can be used to determine in which direction a reaction will proceed at a given point in time. Equilibrium constant is the numerical value of reaction quotient at the end of the reaction, when equilibrium is reached.

If Q = K then the system is already at equilibrium. If Q < Keq, the reaction will move toward the products to reach equilibrium. If Q > Keq, the reaction will move toward the reactants in order to reach equilibrium. Therefore, by comparing Q and K, we can determine the direction of a reaction.

Where Q= reaction quotient and Keq= equilibrium constant for the reaction.

The larger the equilibrium constant, the further the equilibrium lies toward the products. Reaction quotient is a quantity that changes as a reaction system approaches equilibrium.  

We can determine the equilibrium constant  based on equilibrium concentrations. K is the constant of a certain reaction when it is in equilibrium. Equilibrium occurs when there is a constant ratio between the concentration of the reactants and the products.

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