1. Mass-Mass Conversions 56.0 g N 2 x g N 2 g NH 3 28.0 1 1 2 = 1904 = 68.0 1. When nitrogen and hydrogen react, they form ammonia gas, which has the formula NH 3. If 56.0 g of nitrogen are used up in the reaction, how many grams of ammonia will be produced? N 2 + 3 H 2  2 NH 3 mol N 2 x mol NH 3 x 1 17.0 1

2. Mass-Mass Conversions 42.0 g Na 2 O x g Na 2 O g Na 62.0 1 2 4 124 = 3864 = 31.2 2.Sodium metal reacts with oxygen to produce solid sodium oxide. How many grams of sodium must react to produce 42.0 g of sodium oxide? 2. Sodium metal reacts with oxygen to produce solid sodium oxide. How many grams of sodium must react to produce 42.0 g of sodium oxide? 4Na + O 2  2 Na 2 O mol Na 2 O x mol Na x 1 23.0 1

3. Mass-Mass Conversions 12.0 g H 2 x g H 2 g H 2 O 2.0 1 2 2 = 216 = 108 3. When 12.0 g of hydrogen reacts with oxygen, how many grams of water are produced? 2H 2 + O 2  2 H 2 O mol H 2 x mol H 2 O x 1 18.0 1

4. % Yield: Actual Yield: amount of product produced when the reaction is performed in a lab. Theoretical Yield: amount of product expected to be produced based on the balanced equation and the amount of reactants. Percent Yield = ( Actual yield / Theoretical yield) x 100%

5. % Yield 5.99 g C 3 H 8 x g C 3 H 8 g CO 2 44.0 1 1 3 1 = 17.97 = 18.0 1. What is the % yield of carbon dioxide when 5.99 grams of propane are burned and 12.052 grams of carbon dioxide are collected? C 3 H 8 + 5O 2  3CO 2 + 4H 2 O mol C 3 H 8 x mol CO 2 x 1 44.0 1 Theoretical yield Actual yield

6. % Yield = Theoretical g CO 2 18.0 = 1205.2 = 18.0 1. What is the % yield of carbon dioxide when 5.99 grams of propane are burned and 12.052 grams of carbon dioxide are collected? C 3 H 8 + 5O 2  3CO 2 + 4H 2 O Actual x 100 % = 18.0 12.052 Theoretical yield Actual yield = 12.052 g CO 2 x 100 % 67.0 %

7. Limiting and Excess Reagent Limiting Reactant Reactant used up first in a chemical reaction. (Limits amount of product produced!!) Excess Reactant Reactant that is not used up in a chemical reaction (Will have leftover reactant, too much!!)