6.2 Factors Affecting Rates of Reaction & Collision Theory

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

  Temperature, concentration or pressure, surface area, and the presence or absence of a catalyst
• What is the theory behind chemical reactions known as?

  Collision theory
• According to collision theory, what must happen for particles to react?

  Particles must collide with each other with sufficient energy
• What is the term for the minimum energy required for a successful collision?

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

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

  The amount of energy the particles have and the frequency of collisions
• How does an increase in temperature affect the rate of reaction?

  It increases the energy of particles, leading to more frequent and energetic collisions
• What is the relationship between concentration, pressure, and the rate of reaction?

  Increased concentration or pressure leads to more particles per unit volume, increasing collision frequency
• How does surface area affect the rate of reaction?

  A higher surface area increases the frequency of collisions, leading to a higher rate of reaction
• If you wanted to react magnesium with an acid, which form would have the highest rate of reaction?

  Powdered magnesium
• What is the role of a catalyst in a chemical reaction?

  Catalysts speed up a reaction without being consumed in the process
• How does a catalyst affect activation energy?

  A catalyst lowers the activation energy by providing an alternative reaction pathway
• What are some common sources of catalysts?

  Transition metals like cobalt and nickel
• What are enzymes in the context of catalysts?

  Enzymes are catalysts made by living organisms
• What are the four main factors that affect the rate of chemical reactions?

  • Temperature
  • Concentration or pressure
  • Surface area
  • Presence or absence of a catalyst
• What are the key components of collision theory?

  • Particles must collide to react
  • Collisions must have sufficient energy (activation energy)
  • More energy and more frequent collisions increase reaction rate
• How do temperature, concentration, pressure, surface area, and catalysts affect the rate of reaction?

  • Increase energy of particles or collision frequency
  • Higher temperature leads to faster movement
  • Higher concentration/pressure increases particle density
  • Larger surface area increases collision opportunities
  • Catalysts lower activation energy, increasing successful collisions