Final answer:
An increase in temperature leads to a higher reaction rate by increasing the frequency and force of collisions between reactant particles.
Step-by-step explanation:
The rate of a chemical reaction increases when the temperature increases. This is because when the reactant particles are heated, they move faster and collide more frequently with greater force. This increases the chances of effective collisions, where the reactants surmount the activation energy barrier and form products. Therefore, an increase in temperature leads to a higher reaction rate.