C6

• What does the rate of chemical reactions refer to?

  The speed of reactants turning into products
• How can we measure the rate of a chemical reaction?

  By measuring reactants used or products formed
• What is the equation for the rate of reaction based on reactants used?

  Rate = quantity of reactants used / time
• What is the equation for the rate of reaction based on products formed?

  Rate = quantity of products formed / time
• What units can be used to measure quantities in the rate of reaction?

  Grams or cm cubed
• How do you convert 2 minutes into seconds?

  120 seconds
• What is the rate of hydrogen production if 180 cm cubed is produced in 2 minutes?

  1.5 cm cubed per second
• How do you calculate the rate if 3 G of magnesium is used in 4 minutes?

  0.0125 G per second
• What do the calculated rates of reaction represent?

  The average or mean rates throughout the reaction
• How does the rate of reaction change over time?

  • Starts fast with many reactants
  • Slows down as reactants are used up
• How can reaction rates be visualized graphically?

  • Time on x-axis
  • Mass of reactant or volume of product on y-axis
• What happens to the mass of magnesium in a reaction graph?

  It starts high and decreases over time
• What happens to the volume of hydrogen produced in a reaction graph?

  It starts at zero and increases rapidly
• What is another unit that can be used for measuring reaction rates?

  Moles per decimet cubed per second
• How do you calculate the rate in moles per minute if 0.6 moles of magnesium are used in 2 minutes?

  0.3 moles per minute
• What will the next video cover regarding reaction rates?

  • Calculating the rate of reaction at a specific time
• What are the factors that affect the rate of chemical reactions?

  Temperature, concentration, pressure, surface area, catalyst
• What is the theory behind chemical reactions called?

  Collision theory
• What must particles do to react according to collision theory?

  Collide with sufficient energy
• What is the term for the minimum energy required for a successful collision?

  Activation energy
• What happens if particles collide with less energy than the activation energy?

  They bounce apart without reacting
• What two main factors determine the rate of a chemical reaction?

  Energy of particles and collision frequency
• How does increasing the energy of particles affect the rate of reaction?

  It increases the likelihood of surpassing activation energy
• What does collision frequency refer to?

  How often particles collide with each other
• How does temperature affect the rate of reaction?

  Higher temperature increases particle energy and collisions
• What happens to particles as temperature increases?

  They move faster and collide more frequently
• How are concentration and pressure related to the rate of reaction?

  Both increase the number of particles per volume
• What effect does higher surface area have on the rate of reaction?

  It increases the frequency of collisions
• If three grams of magnesium are reacted with acid, which form has the highest reaction rate?

  Powdered magnesium
• What is a catalyst?

  A substance that speeds up a reaction
• How do catalysts affect activation energy?

  They lower the activation energy required
• What do catalysts provide to lower activation energy?

  An alternative reaction pathway
• What is a common source of catalysts?

  Transition metals like cobalt and nickel
• What are enzymes?

  Catalysts made by living organisms
• What are the four main factors affecting the rate of chemical reactions?

  • Temperature
  • Concentration
  • Pressure
  • Surface area
  • Presence of a catalyst
• How do temperature, concentration, pressure, and surface area affect the rate of reaction?

  • Increase energy of particles
  • Increase frequency of collisions
  • Result in more successful collisions
• What is the role of a catalyst in a chemical reaction?

  • Speeds up the reaction
  • Lowers activation energy
  • Provides an alternative pathway
• What is the significance of activation energy in chemical reactions?

  • Minimum energy for successful collisions
  • Determines whether a reaction will occur
  • Influences the rate of reaction
• How do transition metals function as catalysts?

  • Act as catalysts in various reactions
  • Lower activation energy
  • Commonly used in industrial processes
• What can graphs measure in a reaction?

  Mean rate and rate at specific time