The decomposition of hydrogen peroxide H2O2 catalyzed by potassium iodide KI is a well-known reaction in chemistry. The overall reaction can be represented as:2 H2O2 aq 2 H2O l + O2 g Potassium iodide acts as a catalyst, which means it speeds up the reaction without being consumed in the process. The effect of changing the concentration of reactants on the reaction rate and sustainability can be explained using the collision theory and the concept of reaction kinetics.1. Reaction rate: The rate of a chemical reaction depends on the frequency of effective collisions between reactant molecules. As the concentration of reactants increases, the number of molecules per unit volume also increases, leading to a higher probability of effective collisions. Consequently, the reaction rate increases with an increase in the concentration of reactants.In the case of the decomposition of hydrogen peroxide catalyzed by potassium iodide, increasing the concentration of either hydrogen peroxide or potassium iodide will result in a faster reaction rate. This is because more reactant molecules are available to collide and interact with each other, leading to a higher frequency of effective collisions.2. Sustainability: The sustainability of a reaction refers to its ability to proceed until the reactants are completely consumed or until equilibrium is reached. In general, a higher concentration of reactants will lead to a longer-lasting reaction, as there are more reactant molecules available to participate in the reaction.However, it is essential to note that the decomposition of hydrogen peroxide is an exothermic reaction, meaning it releases heat. If the reaction rate is too high due to very high concentrations of reactants, the heat generated may cause the reaction to become uncontrollable or even hazardous. Therefore, it is crucial to maintain an appropriate balance between the concentration of reactants and the reaction rate to ensure the sustainability and safety of the reaction.In summary, increasing the concentration of reactants in the decomposition of hydrogen peroxide catalyzed by potassium iodide will lead to an increased reaction rate. However, it is essential to maintain a balance between the concentration of reactants and the reaction rate to ensure the sustainability and safety of the reaction.