Involving a Limiting Reactant

Manufacturers of cars, bicycles, and appliances order parts in the same proportion as they are used in their products. For example, auto manufacturers order four times as many wheels as engines and bicycle manufacturers order twice as many pedals as seats. Likewise, when chemicals are mixed together so that they can undergo a reaction, they are often mixed in stoichiometric quantities—that is, in exactly the correct amounts so that all reactants run out (are used up) at the same time. 

Let s consider the production of hydrogen for use in the manufacture of ammonia. Ammonia, a very important fertilizer itself and a starting material for other fertilizers, is made by combining nitrogen from the air with hydrogen. The hydrogen for this process is produced by the reaction of methane with water according to the balanced equation 

Let s consider the question. What mass of water is required to react exactly with 249 g of methane  

How much water will just use up all of the 249 g of methane, leaving no water or methane remaining  

Moles of CH4 Use mole ratio izj from balanced cj/ equation Moles of H2O 

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Assume that your friend has missed several chemistry classes and that she has asked you to help her prepare for a stoichiometry test. Unfortunately, because of other commitments, you do not have time to meet face to face. You agree to email your friend a set of point-form instructions on how to solve stoichiometry problems, including those that involve a limiting reactant. She also needs to understand the concept of percentage yield. Write the text of this email. Assume that your friend has a good understanding of the mole concept. 

Sigure 4.6 A reaction involving a limiting reactant. The reaction occurring is 2 NO(g) +... 

Another example of a reaction that involves a limiting reactant is the manufacture of the pure silicon that is used in computer chips or solar cells (Figure... 

In the preceding examples involving a limiting reactant, we first calculated moles of each reactant. Next, we compared the ratio of moles available to the stoichiometric factor from the balanced equation. This identified the limiting reactant. 

Chemical Reactions That Involve a Limiting Reactant... 

Calculations Involving a Limiting Reactant 73 Discussion Questions and Exercises 79... 

IBLG See questions from "Calculations Involving a Limited Reactant ... 

Stoichiometrically Equivalent Molar Ratios from the Balanced Equation 89 Reactions That Involve a Limiting Reactant 93... 

Calculations Involving a Limiting Reactant 106 For Review 113 Key Terms 113 Questions and Exercises 115... 

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