Final answer:
Lowering the temperature decreases the rate of a chemical reaction by reducing the kinetic energy of particles, leading to fewer collisions and less energy to overcome activation energy barriers.
Step-by-step explanation:
The factors that decrease the rate of a reaction include lowering the temperature and are rooted in the kinetic molecular theory of matter. When the temperature is decreased, the kinetic energy of the particles is reduced, which leads to fewer collisions between reacting particles and potentially less energy available to overcome activation energy barriers. Hence, lowering the temperature would result in a slower reaction rate. On the other hand, increasing the concentration of reactants and adding a catalyst are factors that would increase the rate of a reaction. Increased concentration leads to more frequent collisions, while a catalyst provides an alternative pathway with lower activation energy, both of which enhance the reaction rate.