Increasing the temperature generally increases the rate of a photochemical reaction. This is because higher temperatures provide more energy to the reacting molecules, which increases the likelihood of successful collisions and the formation of products. The relationship between temperature and reaction rate can be described by the Arrhenius equation:k = Ae^-Ea/RT where k is the rate constant, A is the Arrhenius constant also known as the pre-exponential factor , Ea is the activation energy, R is the gas constant 8.314 J/molK , and T is the temperature in Kelvin.To predict the effect of changing temperature on the reaction rate, you would need to determine the activation energy Ea and the Arrhenius constant A for the specific photochemical reaction. This can be done experimentally by measuring the reaction rate at different temperatures and then plotting the natural logarithm of the rate constant ln k against the inverse of the temperature 1/T . The slope of the resulting linear plot will be equal to -Ea/R, and the intercept will be equal to ln A .Once you have determined the activation energy and the Arrhenius constant, you can use the Arrhenius equation to predict how the reaction rate will change with temperature. For example, if you increase the temperature, the exponential term in the equation will become less negative, leading to an increase in the rate constant k and thus an increase in the reaction rate. Conversely, if you decrease the temperature, the exponential term will become more negative, leading to a decrease in the rate constant and a slower reaction rate.