Kinetics

• Collision


  Chemical reactions occur when particles of substances collide
• Successful collision


  • Energy greater than or equal to the activation energy
  • Correct particle orientation
• Reaction conditions


  Conditions of a reaction that impact the collisions of the particles
• Changing reaction conditions


  Provides particles with more energy
• Providing particles with more energy

  Increases the likelihood of a collision occurring with sufficient energy to react
• Increasing the likelihood of a collision occurring with sufficient energy

  Increases the rate of reaction
• Maxwell-Boltzmann distribution


  Pattern of energy distribution among molecules in a substance

  
• Changing reaction conditions


  Alters the shape of the Maxwell-Boltzmann distribution curve
• The total area under the Maxwell-Boltzmann distribution curve represents the total number of molecules and must remain constant

  
• Thermal energy


  Energy transferred to a substance when heated
• Thermal energy transfer


  Increases the kinetic energy and movement of molecules
• Increased molecular movement


  Increases collision frequency and energy
• Increased collision frequency and energy

  Increases the number of collisions with energy greater than activation energy
• Increasing reaction temperature


  Increases the rate of reaction
• Increasing temperature


  Shifts the Maxwell-Boltzmann distribution curve to the right
• Increasing concentration or pressure


  Packs molecules closer together
• Packing molecules closer together

  Increases collision likelihood
• Increasing concentration or pressure

  Shifts the Maxwell-Boltzmann distribution curve to the right
• Catalyst


  Substance that increases the rate of reaction without being used up
• How a catalyst works


  • Provides an alternative reaction path with lower activation energy
• Using a catalyst


  Shifts the position of the activation energy in the Maxwell-Boltzmann distribution curve to the left