Final answer:
A catalyst increases the rate of a chemical reaction by providing an alternative reaction pathway with a lower activation energy, thereby allowing more reactant particles to collide effectively and speeding up the reaction.
Step-by-step explanation:
The statement to be completed is: 'The higher the activation energy, the slower the reaction. A catalyst speeds up a reaction by finding an alternate path for the reaction with lower activation energy.'
A catalyst is a substance that increases the rate of a chemical reaction by providing an alternative pathway for the reaction that has a lower activation energy. By lowering the activation energy, a catalyst allows more reactant particles to have the required energy for an effective collision, thus increasing the reaction rate. Additionally, increasing the surface area of a reactant will also lead to an increased reaction rate as it provides more particles available for collisions.