Dynamic Equilibrium

Many reactions are reversible. That is they can proceed in both directions at the same time.

An equilibrium can be established if a reaction occurs in a closed system

Reactions do not stop at equilibrium, but the concentration of products and reactants remains constant because the reaction is proceeding at the same rate in both directions.

This does not mean that there are equal amounts of products and reactant though.

This video explains about Dynamic Equilibrium