Answer: Sometimes, when a chemical reaction takes place, it proceeds for a period of time and then seems to stop before all the reactants are consumed. Chemical equilibrium is the state in which both reactants and products are present in concentrations which have no further tendency to change with time. At equilibrium, with both the forward and reverse reactions taking place at the same rate but the concentration of every species no longer changes. In many chemical reactions equilibrium occurs at the point when essentially all reactants are converted to products, but for other reactions, equilibrium occurs when only part of the reactants is converted into products.
The equilibrium can be affected by a change in temperature in concentration of a reactant or product. The state of equilibrium is especially important in solutions, and there are much vital equilibrium in the chemistry.