Catalyst

• What is a catalyst?


  A substance that speeds up a chemical change - increases the rate of a reaction without being chemically changed or used up during the reaction.
• How do catalysts work?

  It offers an alternative to the products, which has a smaller activation barrier, so more particles can react at a time, increasing the rate of reaction.
• With and without a catalyst:

  
• • Lowering the activation energy increases the frequency of successful collisions, so increasing the rate of reaction.
• • The catalyst provides a surface for the reacting particles to successfully collide with each other - providing the surface area increases the frequency of successful collisions, increasing rate of reaction.
• Effect of a catalyst