To calculate the percentage change in the concentration of reactants and products in a chemical equilibrium, we need to know the initial concentrations of the reactants and products, as well as the balanced chemical equation for the reaction. However, since this information is not provided, I will assume a generic reaction and provide a general approach to solving this problem.Let's consider a generic reaction:A + B C + Dwhere A and B are reactants, and C and D are products. Let's assume that the common ion is C.Initially, let the concentrations be [A] = a, [B] = b, [C] = c, and [D] = d.The equilibrium constant expression is:Kc = [C][D] / [A][B] Now, let's increase the concentration of the common ion C by 0.1 M. The new concentration of C will be c + 0.1.At the new equilibrium, let the change in the concentration of A be -x, B be -x, C be x, and D be x. The new concentrations will be:[A] = a - x[B] = b - x[C] = c + 0.1 + x[D] = d + xThe new equilibrium constant expression is:Kc = [ c + 0.1 + x d + x ] / [ a - x b - x ] Since the temperature has not changed, the value of Kc remains the same:1.5 x 10^-5 = [ c + 0.1 + x d + x ] / [ a - x b - x ] Now, you would need to solve for x, which represents the change in the concentration of the reactants and products. Once you have the value of x, you can calculate the percentage change in the concentration of each species:Percentage change in [A] = x/a * 100Percentage change in [B] = x/b * 100Percentage change in [C] = x/ c + 0.1 * 100Percentage change in [D] = x/d * 100Without the specific initial concentrations and the balanced chemical equation, it is not possible to provide numerical values for the percentage changes. However, this general approach can be applied to any specific reaction with known initial concentrations and a common ion.