1.9 Rate Equations

• What is the rate of reaction?

  Change in concentration of a substance per unit time
• What is the collision theory?


  - For particles to react, they have to collide with each other with sufficient energy and at the correct orientation
• What is activation energy?

  The minimum energy particles need to react
• How does the concentration of a solution affect rate of reaction? Explain why

  The higher the concentration, the faster the reaction (unless the reagent is in zero order) because there are more particles in a given molecule therefore more frequent collisions
• How does the surface area of a solid affect the rate of reaction? Explain why

  The more pieces a solid is broken up into, the greater the surface area. The greater the surface area the faster the reaction because there are more particles available to react therefore more frequent collisions
• How does the pressure of a gas affect rate of reaction?

  The higher the pressure, the faster the reaction (unless that reagent is zero order) because more particles in a given space therefore more frequent collisions
• How does the temperature affect rate of reaction?

  The higher the temperature the faster the reaction because particles have more energy therefore the more particles with an energy greater than the activation energy therefore more frequent successful collisions
• How does a catalyst affect rate of reaction?

  A catalyst is a substance that increases the rate of reaction but is not used up because it lowers the activation energy s more particles with energy greater than the activation energy