Factors affecting the rate of reaction - Topic 6

• Collision theory explains how particles need to collide with enough energy for a reaction to take place.
• For a collision to be successful, the particles must?

  collide and also have enough energy
• What is the minimum amount of energy required for particles to successfully react?

  Activation energy
•  A higher frequency of collisions and particles having more energy increases the chance of ________ _____

  Successful collisions
• The rate of reaction increases if the _______ of collisions increases

  frequency
•  The rate of reaction increases if the particles have more _____

  energy
• What 5 factors affect the rate of reaction?

  Temperature, concentration, surface area, pressure and catalyst
• How does Surface Area affect the Rate of Reaction?

  The smaller the reactants, the larger the SA:V ratio, meaning there is more contact points exposed for reactants, so there is a higher frequency of collisions increasing the chance of successful collisions.
• How does temperature affect the rate of reaction?

  Temperature increases the kinetic energy of the particles, causing them to move faster and increase the frequency of collisions. Meaning a higher percentage of the particles have energy greater than the activation energy, increasing the chance of successful collisions.
• What is concentration?

  How much dissolved solute there is in a given volume of a solvent
• How does concentration affect the rate of reaction?

  The number of particles increases in a given volume ,the concentration increases, increasing the frequency of collisions, increasing the chance of successful collisions.
• Why does the rate of reaction decrease as the reaction takes place?

  Number of reacting particles decrease as they get used up, frequency of collisions decrease, less chance of successful collisions.
• How does pressure affect the rate of reaction?

  The more particles in a given volume, increases the pressure, meaning an increase in the frequency of collisions and increasing the chance of successful collisions
• What are catalysts?

  A chemical substance that speeds up reactions without being affected or used up.
• How does catalysts affect the rate of reaction?

  They lower the activation energy of the particles and provide an alternative pathway. Causing a higher percentage of particles to have more energy than the activation energy, increasing the chance of successful collisions.