rate of reaction

• What does the rate of chemical reactions refer to?

  The speed of reactants turning into products
• Why is it important to measure the rate of a reaction?

  To understand how fast reactants are used or products formed
• How can we measure the rate of a reaction?

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

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

  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?

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

  1.5 cm cubed per second
• What is the rate of magnesium used if 3 g is used in 4 minutes?

  0.0125 g per second
• What do average rates of reaction represent?

  The mean rate throughout the entire reaction
• How does the rate of reaction change over time?

  • Starts fast with many reactants
  • Slows down as reactants are used up
  • Graphs show decreasing mass of reactants or increasing volume of products
• What does the graph of reactant mass over time look like?

  Starts high, falls rapidly, then slows
• What does the graph of product volume over time look like?

  Starts at zero, rises quickly, then levels off
• 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 are the different units for measuring reaction rates?

  • Grams per second
  • cm cubed per second
  • Moles per second
  • Decimet cubed per second
  • Moles per minute