18.1

• what is the definition for rate of reaction?

  change in concentration of a reactant/product per unit time
• Adding a catalyst increases the proportion of collisions that are successful


  True

  provides an alternative route with a lower activation energy

  = more particles with lower energy can now react successfully
• Increasing the concentration of a reactant increases the proportion of collisions that are successful

  • increases frequency of collisions, not proportion of those successful
  • may not be successful due to insufficient kinetic energy
• Increasing the temperature increases the proportion of collisions that are successful


  true

  • more kinetic energy increases the chances of successful collisions
• Increasing the temperature lowers the activation energy


  false

  • only catalysts can lower activation energy
• how can successful collisions be increased?

  • have minimum activation energy
  • collide with correct orientation
• Surface area can be increased by using smaller pieces of a solid reactant


  true

  smaller particles increase the surface area available
• List 4 possible ways you could possibly measure the rate of chemical reactions

  measure:

  1. volume of gas produced
  2. loss of mass
  3. increase of mass
  4. colour change
• what is the formula for rate of reaction?

  Rate of reaction = change in concentration of reactant or product/time
• what is rate constant (k)?

  the constant that links the rate of

  reaction with the concentration of the reactants

  raised to the power of their orders in the rate

  equation
• what is overall order?

  the sum of all the individual orders in a reaction equation
• What does the term ‘order’ mean?

  The order of a reactant is the power (indices) to which the concentration of the reactant is raised by in the rate equation