Percentage yield

• What is the term for the amount of product from a chemical reaction?

  Yield
• How can yield be measured?

  In grams or moles
• What is the actual yield?

  The amount we actually get from a reaction
• What is the theoretical yield?

  The yield expected based on calculations
• If 2 grams of hydrogen reacts with 16 grams of oxygen, what is the theoretical yield of water?

  18 grams
• Why might the actual yield be less than the theoretical yield?

  There are several reasons for this discrepancy
• What is one reason for a lower actual yield?

  Reactants might not fully react
• What is a reversible reaction?

  A reaction that can go in both directions
• In the nitrogen and hydrogen reaction, why doesn't it go to completion?

  It is a reversible reaction
• What is a side reaction?

  When reactants produce unexpected products
• What might happen to nitrogen in the ammonia reaction?

  It could react with oxygen to form nitrogen dioxide
• What is one way product can be lost during a reaction?

  Gaseous products can escape
• What happens when filtering a solution?

  Some liquid or solid may be left behind
• How do you calculate percentage yield?

  Actual yield divided by theoretical yield times 100
• What is the percentage yield if the actual yield is 15 grams and the theoretical yield is 18 grams?

  83.3 percent
• What is the range of percentage yield?

  From 0 percent to 100 percent
• What are the common reasons for lower actual yield in reactions?

  • Reactants might not fully react
  • Side reactions producing different products
  • Loss of product during the process
• How do you determine the efficiency of a chemical reaction?

  • Calculate the percentage yield
  • Compare actual yield to theoretical yield
  • Assess factors affecting yield