The intensity of light can affect the reaction rate of the decomposition of hydrogen peroxide H2O2 catalyzed by potassium iodide KI due to the photolysis of hydrogen peroxide and the effect of light on the catalyst.1. Photolysis of hydrogen peroxide: When hydrogen peroxide is exposed to light, especially ultraviolet UV light, it can undergo a process called photolysis. Photolysis is the decomposition of a chemical compound by the absorption of light. In this case, hydrogen peroxide can break down into water H2O and oxygen O2 when exposed to light:2H2O2 aq + UV light 2H2O l + O2 g As the intensity of light increases, the rate of photolysis of hydrogen peroxide also increases, which can lead to a faster overall decomposition rate.2. Effect of light on the catalyst: The reaction rate of the decomposition of hydrogen peroxide catalyzed by potassium iodide can also be affected by the intensity of light due to the effect of light on the catalyst itself. When potassium iodide is exposed to light, it can undergo a process called photoactivation, in which the light energy can excite the electrons in the iodide ions I- and increase their reactivity. This can lead to a faster reaction rate between the hydrogen peroxide and the iodide ions, thus increasing the overall decomposition rate.In conclusion, the intensity of light can affect the reaction rate of the decomposition of hydrogen peroxide catalyzed by potassium iodide by increasing the rate of photolysis of hydrogen peroxide and by increasing the reactivity of the iodide ions in the catalyst. As the intensity of light increases, the overall decomposition rate of hydrogen peroxide is expected to increase as well.