An increase in the concentration of a reactant or product in a redox reaction affects the equilibrium position 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.If the concentration of a reactant is increased, the system will shift the equilibrium position to consume the added reactant by producing more products. Conversely, if the concentration of a product is increased, the system will shift the equilibrium position to consume the added product by producing more reactants.However, it is important to note that changing the concentration of reactants or products does not change the equilibrium constant K for the reaction. The equilibrium constant is only affected by changes in temperature.Let's consider the following redox reaction as an example:Fe^2+ aq + Ce^4+ aq Fe^3+ aq + Ce^3+ aq Suppose the initial concentrations are as follows:[Fe^2+] = 0.1 M[Ce^4+] = 0.1 M[Fe^3+] = 0.05 M[Ce^3+] = 0.05 MThe equilibrium constant K for this reaction can be calculated using the initial concentrations:K = [Fe^3+][Ce^3+] / [Fe^2+][Ce^4+]K = 0.05 0.05 / 0.1 0.1 K = 0.25Now, let's say the concentration of Fe^2+ is increased by 0.02 M:New [Fe^2+] = 0.1 + 0.02 = 0.12 MTo find the new equilibrium concentrations, we can use the reaction quotient Q and compare it to the equilibrium constant K . The reaction quotient is calculated using the initial concentrations after the change:Q = [Fe^3+][Ce^3+] / [Fe^2+][Ce^4+]Q = 0.05 0.05 / 0.12 0.1 Q = 0.0208Since Q < K, the reaction will shift to the right to reach equilibrium. Let x be the change in concentration for the species involved in the reaction:[Fe^3+] = 0.05 + x[Ce^3+] = 0.05 + x[Fe^2+] = 0.12 - x[Ce^4+] = 0.1 - xNow, we can use the equilibrium constant K to find the new equilibrium concentrations:K = 0.05 + x 0.05 + x / 0.12 - x 0.1 - x 0.25 = 0.0025 + 0.1x + x^2 / 0.012 - 0.22x + x^2 Solving this quadratic equation for x, we get x 0.014.So, the new equilibrium concentrations are:[Fe^3+] = 0.05 + 0.014 0.064 M[Ce^3+] = 0.05 + 0.014 0.064 M[Fe^2+] = 0.12 - 0.014 0.106 M[Ce^4+] = 0.1 - 0.014 0.086 MEven though the equilibrium concentrations have changed, the equilibrium constant K remains the same at 0.25, as it is not affected by changes in concentration.