Rate of Reaction

• Chemical reaction


  A reaction between two substances where new bonds are formed and a new substance is made
• Indicators of a chemical reaction


  • Temperature change
  • Colour change
  • Solid formation
  • Effervescence
• Rate of reaction


  The speed at which a reaction occurs
• Measuring rate of reaction


  • Seeing how much gas is formed per second
  • Using a timer/stopwatch
• To make the reaction faster


  1. Increase the concentration of acid

  2. Add a catalyst

  3. Turn the magnesium to powder

  4. Increase the temperature
• More particles per unit volume


  • The reaction will be faster since there is more reactant
  • More product will be formed at the end since the size of the reactants is positively correlated to the amount of the end product
• Increasing the surface area increases the number of collisions between molecules, increasing the chance that they will react.
• A catalyst speeds up the reaction without being used up or changed itself.
• Temperature affects the kinetic energy of the particles, which can increase the frequency of successful collisions and therefore the rate of reaction.
• A catalyst speeds up reactions by providing an alternative pathway with lower activation energy.
• Temperature affects the kinetic energy of particles, leading to increased frequency of successful collisions and higher rates of reaction.
• Catalysts are not consumed during the reaction and remain unchanged at the end.
• Activation Energy (Ea) - The minimum energy required for atoms/molecules to come together and form products.
• Concentration affects the likelihood of successful collisions, as more molecules mean more opportunities for collision.
• Surface area affects the likelihood of successful collisions, as larger surfaces offer more chances for particle interactions.
• Concentration refers to how many particles of substance there are per unit volume.
• Rate of Reaction = [Product] / Time
• Collision theory


  Explains the rate of a reaction in terms of how likely collisions between particles are
• The more collisions, the more likely particles are to react with one another
• Not all collisions result in a reaction
• Particles need sufficient energy to react
• More frequent collisions


  More successful collisions
• More successful collisions


  Faster reaction rate
• Factors affecting rate of reaction


  • Temperature
  • Concentration
  • Pressure
  • Surface area
  • Catalyst
• How increasing factors affect rate of reaction

  1. Temperature: Increases particle energy, increases collision frequency

  2. Concentration: Increases number of particles, increases collision frequency

  3. Pressure: Decreases particle spacing, increases collision frequency

  4. Surface area: Increases collision area, increases collision frequency

  5. Catalyst: Lowers activation energy, increases successful collisions