Factors Affecting Rates of Reaction & Collision Theory

• What are the factors that affect the rate of chemical reactions?

  Temperature, concentration, pressure, surface area, catalyst
• What is the theory behind chemical reactions called?

  Collision theory
• What must particles do to react according to collision theory?

  Collide with sufficient energy
• What is the term for the minimum energy required for a reaction?

  Activation energy
• What happens if particles collide with less energy than the activation energy?

  They bounce apart without reacting
• What two main factors determine the rate of a chemical reaction?

  Energy of particles and collision frequency
• How does increasing temperature affect particle movement?

  Particles move faster and collide more frequently
• What is the effect of increased temperature on the rate of reaction?

  Higher rate of successful collisions
• How are concentration and pressure related to the rate of reaction?

  Both increase collision frequency
• What does higher surface area do to the rate of reaction?

  Increases the rate of reaction
• How would using powdered magnesium affect a reaction with acid?

  It increases the reaction rate
• What is the role of a catalyst in a chemical reaction?

  Speeds up the reaction without being used
• How does a catalyst affect activation energy?

  It lowers the activation energy
• What is a common source of catalysts?

  Transition metals like cobalt and nickel
• What are enzymes in biological systems?

  Catalysts made by living organisms
• What are the key factors affecting the rate of chemical reactions?

  • Temperature
  • Concentration
  • Pressure
  • Surface area
  • Presence of a catalyst
• What is collision theory and its significance in chemical reactions?

  • States that particles must collide to react
  • Requires sufficient energy for successful collisions
  • Activation energy is the minimum energy needed
• How do temperature, concentration, pressure, and surface area affect reaction rates?

  • Increase energy of particles
  • Increase frequency of collisions
  • Result in more successful collisions
• How does a catalyst function in a chemical reaction?

  • Lowers activation energy
  • Provides an alternative reaction pathway
  • Increases proportion of successful collisions
• What are some examples of catalysts in reactions?

  • Transition metals (cobalt, nickel)
  • Enzymes (biological catalysts)