1. P ERCENT Y IELD

2. OBJECTIVE I can calculate percent yield of a reaction

3. T HEORETICAL Y IELD Theoretical yield is the maximum amount of product that could be formed from given amounts of reactants. Theoretical yield is calculated using the gram to gram stoichiometry roadmap.

4. A CTUAL Y IELD Actual yield is actual measured amount of product formed when the reaction is carried out in the lab. Actual yield is an experimental value. You do an experiment and measure the mass of the product formed.

5. P ERCENT Y IELD Percent yield is the ratio of the actual yield to the theoretical yield expressed as a percent.

6. Example 1: 2 H 2 + O 2  2H 2 O Using stoichiometry, you calculate that a reaction of oxygen gas in an excess of hydrogen gas would yield 28.3 g of water. 28.3 g H 2 O = theoretical yield Perform the experiment in the lab and you measure 26.3 g of water produced. 26.3g H 2 O = actual yield

7. Example 1: 2 H 2 + O 2  2H 2 O You calculate that a reaction of oxygen gas in an excess of hydrogen gas would yield 28.3 g of water. 28.3 g H 2 O = theoretical yield Perform the experiment in the lab and you measure 26.3 g of water produced. 26.3g H 2 O = actual yield

8. E XAMPLE 2 Balance the equation. ____NO 2 + ____H 2 O  ____HNO 3 + ____NO

9. E XAMPLE 2 3 NO 2 + H 2 O  2 HNO 3 + NO a. 9.55 g of NO 2 will be used in this reaction. Calculate the amount (grams) of HNO 3 that is possible to produce with this amount of NO 2. (the theoretical yield) 9.55 g NO 2 x _____________ x _____________ x ____________ = ______ g HNO 3

10. E XAMPLE 2 3 NO 2 + H 2 O  2 HNO 3 + NO a. 9.55 g of NO 2 will be used in this reaction. Calculate the amount (grams) of HNO 3 that is possible to produce with this amount of NO 2. (the theoretical yield) 9.55 g NO 2 x = 8.72 g HNO 3 46.0 g NO 2 3 mol NO 2 1 mol NO 2 x 2 mol HNO 3 x 1 mol HNO 3 63.0 g HNO 3 Theoretical Yield

11. E XAMPLE 2 – THE PERCENT YIELD In the lab, an excess of water is mixed with the NO 2, and the reaction is allowed to run until completion. The products are weighed and there is 7.23 g of HNO 3 left over (the actual yield). Calculate the percent yield of the experiment.

12. E XAMPLE 2 In the lab, an excess of water is mixed with the NO 2, and the reaction is allowed to run until completion. The products are weighed and there is 7.23 g of HNO 3 left over (the actual yield). Calculate the percent yield of the experiment.

13. E XAMPLE 2 In the lab, an excess of water is mixed with the NO 2, and the reaction is allowed to run until completion. The products are weighed and there is 7.23 g of HNO 3 left over (the actual yield). Calculate the percent yield of the experiment.

14. OBJECTIVE I can calculate percent yield of a reaction