Module 6 Intro

Module 6—Stoichiometry

Reflect and Connect

Module Assessment (Part 1)—Stoichiometry Calculator

In this lesson you have learned to calculate the number of moles of an unknown substance by using a mole ratio. You may have identified that this calculation is one that you may be asked to perform many times. Our society routinely uses technology to perform many routine, or repetitive, tasks. When calculations are required, spreadsheets or computer programs are often used. In this exercise you will use your knowledge of stoichiometry to construct an automatic mole calculator that will calculate the moles for each of the substances listed in the balanced chemical equation. You will use the moles for one species and the coefficients provided in the balanced chemical equation. You will also write instructions on how to use your calculator.

Submit an electronic version of your calculator and the instructions for its use to your teacher along with a brief explanation of how it was constructed. Provide an example of how you tested the calculator to ensure that it works properly. Your teacher will review your work and provide feedback. You are welcome to use any feedback to modify and improve your work. Save copies of your work and the feedback from your teacher in your course folder. In the next lessons you will be asked to add other aspects to your Stoichiometry Calculator. At the completion of this module, you will submit your completed Stoichiometry Calculator and instructions as the Module Assessment.

Reflect on the Big Picture

How does your understanding of stoichiometry help you understand a chemical system with an intended purpose? Earlier in this lesson you learned that the quantities of reactants involved in a chemical reaction can influence the quantities of products. You also learned that knowledge of the ratio by which substances react is important in the design of a reaction.

How is an understanding of stoichiometry used in cooking? In Module 5, Lesson 2, you experimented with baking soda, and you found that it would produce carbon dioxide gas with the addition of water.

Another commonly used baking product is baking powder, which contains sodium hydrogen carbonate and tartaric acid mixed together as solids. In what proportions must the components be present in order for baking powder to achieve its desired purpose? How does the design of baking powder represent an understanding of stoichiometry and provide convenience for people using the product? Place a copy of your answers in your course folder and send a copy to your teacher.

Assessment

Submit the following assessment items to your teacher:

• Module 6: Lesson 1 Assignment

• Discuss

• Reflect on the Big Picture

• Module Assessment (Part 1)—Stoichiometry Calculator