Identifying the Limiting Reagent in Stoichiometry

This video tutorial, part of a stoichiometry series, explains how to identify limiting reagents and calculate reaction yields. It uses a s'mores analogy to illustrate the concept of limiting reagents and theoretical yield. The tutorial then applies these concepts to a chemical reaction involving magnesium and nitrogen, demonstrating how to determine the limiting reagent and calculate the theoretical yield. Finally, it covers how to calculate the percent yield based on actual and theoretical yields, emphasizing the importance of these calculations in chemistry.

What is the limiting reagent in the s'mores example?

• Graham crackers

• Marshmallows

• Chocolate bars

• None of the above

How many s'mores can be made according to the theoretical yield in the s'mores example?

• 24

• 20

• 40

• 27

What is the product of magnesium and nitrogen reaction?

• Nitrogen gas

• Magnesium oxide

• Magnesium nitrate

• Magnesium nitride

What is the molar mass of magnesium used in the calculations?

• 45 grams per mole

• 100.9 grams per mole

• 28 grams per mole

• 24.3 grams per mole

How many grams of nitrogen were used in the reaction?

• 75 grams

• 162 grams

• 45 grams

• 104 grams

Which reactant is the limiting reagent in the magnesium and nitrogen reaction?

• Magnesium

• Nitrogen

• Both are limiting

• Neither is limiting

What is the theoretical yield of magnesium nitride?

• 104 grams

• 88.7 grams

• 200 grams

• 162 grams

What is left in excess after the magnesium and nitrogen reaction?

• None of the above

• Magnesium nitride

• Nitrogen

• Magnesium

What is the percent yield of the reaction if 88.7 grams of magnesium nitride were collected?

• 100%

• 75%

• 85%

• 95%

Why is the actual yield different from the theoretical yield?

• Both A and B

• Theoretical yield is always higher

• Reaction inefficiencies

• Errors in measurement