The equilibrium constant (K) is a number that shows the ratio of products to reactants when a reversible reaction is at equilibrium.
- It tells us how far a reaction goes towards forming products or staying with reactants.
- If K is large, it means the reaction favors products (more products are present at equilibrium).
- If K is small, it means the reaction favors reactants (more reactants remain at equilibrium).
- If K is around 1, both reactants and products are present in similar amounts.
In short: The equilibrium constant is a measure of the extent of a reaction at equilibrium.