The reaction between potassium iodide KI and hydrogen peroxide H2O2 in an acidic medium can be represented by the following equation:2KI + H2O2 + 2H+ 2K+ + 2I2 + 2H2OTo determine the rate law for this reaction, we need to know the order of the reaction with respect to each reactant. The order of the reaction can be determined experimentally by measuring the initial rates of the reaction at different initial concentrations of the reactants.Let's assume that the order of the reaction with respect to KI is m, and the order with respect to H2O2 is n. The rate law for the reaction can be written as:Rate = k[ KI]^m [H2O2]^nwhere k is the rate constant.Experimental data for this reaction typically show that the reaction is first order with respect to both KI and H2O2. Therefore, m = 1 and n = 1. The rate law for the reaction between potassium iodide and hydrogen peroxide in an acidic medium is:Rate = k[ KI][H2O2]The overall order of the reaction is the sum of the individual orders, which is m + n = 1 + 1 = 2. So, the reaction is second order overall.