Factors affecting rate

• Rate of Reaction -

  The number of particle collisions per second.
• Successful collisions require:

  • head-on collisions
  • Enough energy to over come the activation energy
• Progress of Reactions

  • Rate of reaction is steady to begin with as there are lots of reactant particles
  • Rate of reaction then slows down as reactant particles are used up
  • Reaction stops when there are no more reactant particles
• Increasing Temperature

  • Particles have more kinetic energy
  • Collisions have more energy
  • More frequent successful collisions
• Increasing Concentration/ pressure

  • Higher number of particles
  • More collisions
  • More frequent successful collisions
• Increasing Surface Area

  • Higher number of surfaces
  • More collisions
  • More frequent successful collisions
• Adding a catalyst

  • Alternate pathway
  • Lower activation energy
  • More frequent successful collisions