2 Limiting Reagent and Percent Yield 12.3Limiting Reagent and Percent YieldIf a carpenter had two tabletops and seven table legs, he could only build one four-legged table. The number of table legs is the limiting factor in the construction of four-legged tables. Similarly, in chemistry, the amount of product made in a chemical reaction may be limited by the amount of one or more of the reactants.
3 Limiting and Excess Reagents 12.3Limiting and Excess ReagentsLimiting and Excess ReagentsHow is the amount of product in a reaction affected by an insufficient quantity of any of the reactants?
4 Limiting and Excess Reagents 12.3Limiting and Excess ReagentsIn a chemical reaction, an insufficient quantity of any of the reactants will limit the amount of product that forms.The limiting reagent is the reagent that determines the amount of product that can be formed by a reaction.
5 Limiting and Excess Reagents 12.3Limiting and Excess ReagentsIn the reaction of nitrogen and hydrogen, hydrogen is the limiting reagent. Nitrogen is the reagent that is not completely used up in the reaction. The reagent that is not used up is called the excess reagent.
6 Limiting and Excess Reagents 12.3Limiting and Excess ReagentsThe Chemical Equation for the Preparation of AmmoniaThe “recipe” calls for 3 molecules of H2 for every 1 molecule of N2 . In this particular experiment, H2 is the limiting reagent and N2 is in excess. Inferring How would the amount of products formed change if you started with four molecules of N2 and three molecules of H2?
7 Limiting and Excess Reagents Animation 13Apply the limiting reagent concept to the production of iron from iron ore.
17 for Sample Problem 12.8Problem Solving Solve Problem 28 with the help of an interactive guided tutorial.
18 Percent Yield 12.3 What does the percent yield of a reaction measure?
19 A batting average is actually a percent yield. 12.3Percent YieldThe percent yield is a measure of the efficiency of a reaction carried out in the laboratory.A batting average is actually a percent yield.A batting average is actually a percent yield.
20 12.3Percent YieldThe theoretical yield is the maximum amount of product that could be formed from given amounts of reactants.In contrast, the amount of product that actually forms when the reaction is carried out in the laboratory is called the actual yield.
21 12.3Percent YieldThe percent yield is the ratio of the actual yield to the theoretical yield expressed as a percent.
33 12.3 Section Quiz.1. In the reaction 3NO2 + H2O 2HNO3 + NO, how many grams of HNO3 can form when g of NO2 and 2.25 g of H2O are allowed to react?0.913 g0.667 g15.7 g1.37 g
34 12.3 Section Quiz.2. How many grams of H2O can be formed from g O2 and 6.00 g H2?30.0 g27.0 g54.0 g13.5 g
35 12.3 Section Quiz.3. Octane burns according to the following equation.2C8H O2 16CO2 + 18H2OWhat is the percent yield if 14.6 g of CO2 are produced when 5.00 g of C8H18 are burned?106%94.8%34.2%62.5%
36 Solve the Concept Map with the help of an interactive guided tutorial.