What is the Difference Between Equilibrium Constant and Reaction Quotient?

The main differences between the equilibrium constant (K) and the reaction quotient (Q) are:

1. Time: K represents the concentrations at equilibrium, while Q can use the concentrations at any given time during the reaction.
2. Value: The value of Q changes during a reaction, whereas the value of K does not change unless the temperature changes.
3. Equilibrium: Q can be calculated at any point during the reaction, whether it is at equilibrium or not. In contrast, K is calculated only when the reaction reaches equilibrium.
4. Comparison: By comparing Q and K, we can determine in which direction the reaction will proceed initially.

In summary, the equilibrium constant (K) is a measure of the reaction's state at equilibrium, while the reaction quotient (Q) describes the state of the system with respect to equilibrium at any given time during the reaction. Comparing Q and K allows us to understand the direction in which the reaction will proceed.

Comparative Table: Equilibrium Constant vs Reaction Quotient

The equilibrium constant (K) and the reaction quotient (Q) are both used to describe the state of a chemical reaction with respect to equilibrium. However, they differ in several aspects:

In summary, the equilibrium constant (K) is a constant value that represents the ratio of products to reactants at equilibrium, while the reaction quotient (Q) is a variable value that represents the ratio of products to reactants at any point during the reaction. Comparing Q and K can help determine the direction in which a reaction will proceed to reach equilibrium.