Physical Science SHS 11.1 Calculating the Percent Yield.pptx

Calculating the percent yield. Lesson for senior high school students

1. Lesson 11.1 Calculating the Percent Yield

2. calculate the theoretical yield and percent yield of a chemical reaction. 1 At the end of the lesson, you should be able to:

3. Chemical reactions do not occur with 100% efficiency. The efficiency of chemical reactions can be measured using percent yields. The Percent Yield

4. It represents the percentage of successful reactions with respect to the total number of reactions that occured. But before you can calculate percent yield, you need to identify first theoretical and actual yields. The Percent Yield

5. Theoretical yield refers to the maximum amount of product that could possibly be produced in a chemical reaction. This is calculated using stoichiometry given the amounts of reactants. The Percent Yield

6. The actual yield refers to the amount of product that was produced experimentally for a chemical reaction. The actual yield is always less than the theoretical yield. The Percent Yield

7. There are several factors affecting the actual yield such as errors in the experiment, formation of side products, and completion of the reaction. Errors in performing the experiments, which results in the loss of reactants or products may lessen the actual yield. Some reactions have products formed other than those in the main reaction observed, these are called side products. The Percent Yield

8. The percent yield mathematically refers to the efficiency of a chemical reaction. It is calculated by getting the ratio of the actual yield and theoretical yield multiplied by 100. The formula is shown below: The Percent Yield

9. Calcium carbonate decomposes in the presence of heat to form calcium oxide and carbon dioxide. When 5 g of calcium carbonate was heated, 1.35 g of calcium oxide was produced. If the theoretical yield for calcium oxide is 1.5 g, what is the percent yield?

10. When 5 g of calcium carbonate was heated, 1.35 g of calcium oxide was produced. If the theoretical yield for calcium oxide is 1.5 g, what is the percent yield? Step 1: Identify what is required. You are calculating for the percent yield.

11. When 5 g of calcium carbonate was heated, 1.35 g of calcium oxide was produced. If the theoretical yield for calcium oxide is 1.5 g, what is the percent yield? Step 2: Identify the given. You are given the balanced chemical equation. You are also given the theoretical yield (1.5 g) and actual yield (1.35 g)

12. When 5 g of calcium carbonate was heated, 1.35 g of calcium oxide was produced. If the theoretical yield for calcium oxide is 1.5 g, what is the percent yield? Step 3: Write the working equation.

13. When 5 g of calcium carbonate was heated, 1.35 g of calcium oxide was produced. If the theoretical yield for calcium oxide is 1.5 g, what is the percent yield? Step 4: Substitute the given values.

14. When 5 g of calcium carbonate was heated, 1.35 g of calcium oxide was produced. If the theoretical yield for calcium oxide is 1.5 g, what is the percent yield? Step 5: Find the answer Therefore, the reaction had 90% yield.

15. Theoretical yield is the maximum amount of product that can be produced in a reaction. Actual yield is the amount of product obtained from a specific experiment. 1 2 Percent yield is calculated by getting the ratio of the actual yield and theoretical yield multiplied by 100. 3

16. Assess if the following statements are true or false. Chemical reactions always proceed with 100% efficiency. Actual yield is also referred to as the experimental yield. Theoretical yield can be mathematically determined from stoichiometric calculations. Percent yield represents the ratio of the theoretical yield to the actual yield multiplied by 100. Side products increase the percent yield.

17. The reaction between acetic acid and ammonia produces ammonium acetate. What amount of acetic acid (MM = 60.05 g/mol) is needed to produce 12 g ammonium acetate (MM = 77.08 g/mol) if the reaction has a 75% yield?

18. Brown, Theodore E., et al. 2012. Chemistry: The Central Science. 12th ed.: Pearson Prentice Hall. Pearson Education Inc. Whitten, Kenneth W., et al. 2007. Chemistry. 8th ed. California. Thomson Higher Education.