Le Chatelier's principle states that if a change is made to a system at equilibrium, the system will adjust itself to counteract that change and restore a new equilibrium. In the context of a chemical reaction, this means that if the concentration of one of the reactants is altered, the reaction will shift in a direction that counteracts the change and re-establishes equilibrium.If the concentration of one of the reactants is increased, the system will respond by shifting the equilibrium position to consume the excess reactant. This means that the reaction will shift in the direction of the products. The increased concentration of the reactant will cause the reaction to proceed faster in the forward direction, producing more products and consuming the added reactant until a new equilibrium is established.On the other hand, if the concentration of one of the reactants is decreased, the system will respond by shifting the equilibrium position to replenish the lost reactant. This means that the reaction will shift in the direction of the reactants. The decreased concentration of the reactant will cause the reaction to proceed faster in the reverse direction, consuming products and producing more reactants until a new equilibrium is established.In summary, according to Le Chatelier's principle, if the concentration of a reactant is increased, the reaction will shift towards the products, and if the concentration of a reactant is decreased, the reaction will shift towards the reactants. This shift in the equilibrium position helps to counteract the change in concentration and re-establish a new equilibrium state.