Kinetics

• What is the activation energy (EA)?

  Minimum energy needed for a reaction
• What does the Maxwell-Boltzmann energy distribution illustrate?

  Spread of energies in gas or liquid
• Why does the energy distribution curve go through the origin?

  There are no molecules with no energy
• Why should the energy distribution curve never meet the x-axis?

  There is no maximum energy for molecules
• Where is the mean energy of particles located on the curve?

  Not at the peak of the curve
• What does the area under the Maxwell-Boltzmann curve represent?

  Total number of particles present
• Why do a few particles have low energies?

  Collisions cause some particles to slow down
• How many particles typically have energy greater than the activation energy?

  Only a few particles have energy > EA
• What is the Emp in the context of energy distribution?

  Most probable energy of particles
• What happens to the energy distribution as temperature increases?

  More molecules have higher energies
• What remains constant when temperature increases in the energy distribution?

  Total area under the curve remains constant
• How does the range of energies change with temperature?

  Molecules have a wider range of energies
• What happens to the Emp and mean energy at higher temperatures?

  Both shift to higher energy values
• What is required for reactions to occur?

  Collisions with sufficient energy
• What is the usual unit for measuring the rate of reaction?

  mol dm^-3s^-1
• How is the rate of reaction determined from a concentration vs. time graph?

  Gradient of the curve indicates the rate
• What is the initial rate of a reaction?

  Rate at the start of the reaction
• What topic is the video about?

  Kinetics
• How can reaction rates be calculated from graphs?

  By drawing a tangent and calculating gradient
• What effect does increasing concentration have on reaction rates?

  Increases frequency of effective collisions
• How is kinetics related to rates of reaction?

  Kinetics is comparable to rates of reaction
• How does the shape of the energy distribution curve change with increased concentration?

  Curves become higher, area increases
• What must happen for a reaction to occur?

  A and B must collide
• What happens to the number of molecules with energy > EA when concentration increases?

  More molecules have energy > EA
• What are the two outcomes of a collision between reactants?

  Nothing happens or a reaction occurs
• What is the activation energy?

  Minimum energy required for a reaction
• How do different volumes of the same initial concentrations affect reaction rates?

  Same initial rate, different final amounts
• How is activation energy similar to a fee?

  It's the cost to initiate a reaction
• What factors increase the rate of reaction?

  Higher concentration, temperature, surface area
• What does a qualitative graph of a reaction show?

  Reaction progress over time without numbers
• How is the reaction rate measured in the sodium thiosulfate and hydrochloric acid experiment?

  As 1/time for cross disappearance
• What happens to the reaction rate if the concentration is halved?

  The reaction rate decreases
• Why is measuring 1/time an approximation for reaction rate?

  It does not include concentration
• What effect does increasing surface area have on reaction rates?

  Increases frequency of successful collisions
• How does increasing concentration affect collisions?

  More particles lead to more collisions
• What does a steeper line on a reaction graph indicate?

  A faster reaction rate
• What is the definition of a catalyst?

  Increases reaction rates without being used
• What effect does higher temperature have on reaction rates?

  Increases energy and frequency of collisions
• How do catalysts increase reaction rates?

  By providing an alternative route with lower EA
• What is the Maxwell-Boltzmann distribution curve used for?

  To show energy distribution of particles