Kinetics

Cards (26)

  • What is the collision theory?
    The collision theory states that chemical reactions occur when particles collide with sufficient energy and correct orientation.
  • What is the “sufficient energy“ known as?
    Activation energy
  • What is activation energy?

    Activation energy is the minimum amount of energy required for a chemical reaction to occur.
  • Why do most collisions not lead to a reaction?

    Insufficient energy and incorrect orientation
  • What does the Maxwell Boltzmann distribution show?

    The spread of energies that molecules of a gas or liquid have at a particular temperature
  • What does the Maxwell Boltzmann distribution graph start at 0,0?
    There are no molecules with no energy
  • What is the area under the curve equal to?
    Total number of molecules
  • What is the speed of particles?

    1. The particles have little energy and move slowly
    2. Most particles move with moderate speeds
    3. Particles with energy greater than the activation energy can react
  • What does this line represent?
    Activation energy
  • What does this line represent?
    The mean energy of the particles
  • What does this line represent?
    The most probable energy (mode)
  • What is this graph called?
    Maxwell Boltzmann distribution graph
  • What does this curve show?
    Effect of increase in temperature on rate of reaction
  • How does an increase in temperature affect the normal rate of reaction graph?
    1. The curve shifts to the RIGHT
    2. The peak is LOWER
    3. The area under the graph is the SAME
    4. Area under the curve beyond the activation energy INCREASES
  • What does this curve show?
    Effect of decrease in temperature on rate of reaction
  • How does the decrease in temperature affect the normal rate of reaction graph?
    1. The curve shifts to the LEFT
    2. Peak is HIGHER
    3. The area under the curve is the same
    4. The area under the curve beyond the activation energy DECREASES
  • Why does a small temperature increase lead to a large increase in rate of reaction?
    The combination of more collisions and energetic collisions
  • Explain how a decrease in temperature affects rate of reaction.
    1. Fewer particles will have energy greater than or equal to the activation energy
    2. Fewer successful collisions in a given time
  • How does an increase in pressure and concentration affect the rate of reaction?
    1. Particles are closer together and collide more often
    2. More frequent collisions
    3. Higher chance of a reaction
  • What happens to the proportion of molecules exceeding the activation energy when a catalyst is present?
    The proportion increases as the activation energy is lower
  • What happens to the rate of reaction when a catalyst is introduced?
    Increases
  • Will the area under the curve differ when the concentration is increased?
    Yes because there are more particles, meaning the peak will be higher
  • What happens to the mean and the Emp when the concentration is increased?

    They stay the same
  • In the Maxwell-Boltzmann graph what goes on the Y-axis?
    Number of molecules or particles
  • In the Maxwell Boltzmann graph what goes on the X-axis?
    Activation energy
  • What is EMP?
    Most probable energy