The reaction quotient (Q) is a number that helps us predict the direction in which a reaction will proceed before it reaches equilibrium.
- Q is calculated the same way as the equilibrium constant (K), but it uses the current amounts of reactants and products, not just the equilibrium values.
- By comparing Q with K, we can tell what will happen next:
- If Q < K, the reaction moves forward (more products will form).
- If Q > K, the reaction moves backward (more reactants will form).
- If Q = K, the system is already at equilibrium.
In short: Q shows the present state of a reaction and whether it still needs to shift forward or backward to reach equilibrium.