Changing the concentration of reactants or products affects the equilibrium position of a chemical reaction according to 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 equilibrium position to counteract the change.When the concentration of reactants or products is changed, the system will shift its equilibrium position to re-establish equilibrium. If the concentration of a reactant is increased, the system will shift towards the products to consume the excess reactant. Conversely, if the concentration of a product is increased, the system will shift towards the reactants to consume the excess product.For example, consider the following reversible reaction:N2 g + 3H2 g 2NH3 g This reaction represents the synthesis of ammonia NH3 from nitrogen N2 and hydrogen H2 gases. At equilibrium, the rate of the forward reaction formation of NH3 is equal to the rate of the reverse reaction decomposition of NH3 .Now, let's say we increase the concentration of nitrogen gas N2 in the system. According to Le Chatelier's Principle, the system will shift its equilibrium position to counteract this change. In this case, the system will shift towards the products NH3 to consume the excess N2. As a result, the rate of the forward reaction will temporarily increase, and more ammonia will be produced until a new equilibrium is established.On the other hand, if we were to increase the concentration of ammonia NH3 , the system would shift towards the reactants N2 and H2 to consume the excess NH3. The rate of the reverse reaction would temporarily increase, and more nitrogen and hydrogen gases would be produced until a new equilibrium is reached.In summary, changing the concentration of reactants or products affects the equilibrium position of a chemical reaction by causing the system to shift its equilibrium position in a direction that counteracts the change, according to Le Chatelier's Principle.