The effect of changes in the concentration of reactants and products on the rate of a chemical reaction that is in equilibrium can be explained using Le Chatelier's principle. This principle states that if a system at equilibrium is subjected to a change in concentration, temperature, or pressure, the system will adjust its position to counteract the change and restore a new equilibrium.When the concentration of reactants or products in a chemical reaction at equilibrium is changed, the system will respond in the following ways:1. If the concentration of a reactant is increased, the system will shift towards the products to consume the excess reactant, thereby increasing the rate of the forward reaction and re-establishing equilibrium.2. If the concentration of a product is increased, the system will shift towards the reactants to consume the excess product, thereby increasing the rate of the reverse reaction and re-establishing equilibrium.3. If the concentration of a reactant is decreased, the system will shift towards the reactants to produce more of the reactant, thereby increasing the rate of the reverse reaction and re-establishing equilibrium.4. If the concentration of a product is decreased, the system will shift towards the products to produce more of the product, thereby increasing the rate of the forward reaction and re-establishing equilibrium.In summary, changes in the concentration of reactants and products affect the rate of a chemical reaction at equilibrium by shifting the position of the equilibrium to counteract the change and restore a new equilibrium state. This shift in equilibrium position results in either an increase or decrease in the rate of the forward or reverse reactions, depending on the specific change in concentration.