Using AACT Resources to Help Teach Stoichiometry

As chemistry teachers around the country plan activities for their students, AACT will be highlighting resources from our high school resource library that can be used to reinforce topics in different units throughout the school year. Our last post highlighted resources that could be used to support a Chemical Equations unit. We will now focus on articles, videos, simulations, and activities that could be used in a Stoichiometry unit.

Since our original post in January 2018, we have added a few more resources that you might consider trying with your students. Additionally, we have created a unit plan that uses many of our resources to help you teach a unit on Stoichiometry.

Use one of our new lesson plans to teach your students how to approach stoichiometry problems:

• The lesson, Map It Out! shows students how to solve stoichiometry problems using a graphic organizer and Cornell notes. This six step process includes writing a balanced equation, identifying the known and unknown substances, selecting the correct mole ratio, determining the path to a solution, using conversion factors and calculating the theoretical yield.
• The Stoichiometry Set-up Method lesson plan shows students how to follow a process of visual cues in combination with a step-by-step problem solving method for different types of stoichiometric problems. This method can be particularly beneficial for students who struggle with completing multi-step calculations. Read more about this lesson in the September 2015 issue of Chemistry Solutions.

Students can participate in a quiz that challenges their knowledge of reaction types, balancing equations and solving stoichiometry problems with the Chemical Reactions and Stoichiometry simulation. During this quiz based activity, students are presented with five different reactions to analyze, each having three related questions to answer. The questions are randomized so students will not have the same order as their peers. Additionally, there are 20 possible chemical equations in the quiz, so students can complete it several times without receiving the same problems.

Connect stoichiometry to real life with one of our new lessons about the chemistry of airbags.

• In the first lesson plan, Stoichiometry of Air Bags, students are introduced to the concept of gram to gram stoichiometry calculations through a scenario regarding air bags. They are tasked with calculating the amount of sodium gas (NaN3) that must be produced to inflate a vehicle air bag to the correct size. Follow-up practice problems are also provided.
• The second lesson plan, Mechanisms and Properties of Airbags, teaches students about the mechanisms and properties of airbags, and examines the choice of airbag inflator from several points of view. This lesson is part of the resources put together by the 2016 AACT-Ford Content Writing Team and includes NGSS alignment along with links to several short videos about airbags.

Introduce the concept of limiting reactants by using a teacher demo or one or more of our student activities.

• Allow your students to observe a series of reactions between acetic acid and sodium bicarbonate with the Introducing Limiting Reactants demonstration. After observing the reactions, students analyze the quantities of reactants used as well as the results in order to understand the concept of limiting reactants. They will also determine if the reaction is an endothermic or exothermic process based on their observations.
• If you prefer a hands on activity rather than a teacher demonstration, use the lab, Limiting Reactant in a Balloon to allow your students to perform a reaction between acetic acid and sodium bicarbonate to determine the amount of product formed and the limiting reactant.
• Students can investigate the idea of limiting reactant using a brownie recipe with the Limiting Reactants in Brownies. In a similar lab, Limiting Reactant Candy, students use candy to help them understand what is meant by the term, "limiting reactant" and identify it in a non-chemistry situation. One more activity, Cookie Stoichiometry, has students answer stoichiometry related questions using a chocolate chip cookie recipe.
• Your students can get practice drawing particle diagrams to demonstrate stoichiometry and limiting reactants with the Limiting Reactant Activity.

We also have several resources that can be used as a culminating activity for a stoichiometry unit.

• Use the activity, Calculating Your Carbon Footprint to assess your student’s understanding of the topic. In this activity, students apply their knowledge of writing and balancing chemical equations as well as stoichiometry calculations to estimate their carbon footprint and then reflect on their carbon footprint and what it means. Read more about this lesson in the May 2017 issue of Chemistry Solutions.
• Students create a stoichiometric mixture of hydrogen and oxygen gases to launch a soda bottle rocket in the Launching Rockets lab. In addition to student activity sheets, this resource includes comprehensive teacher notes, video instructions and NGSS alignment.

We hope that these activities can help you to reinforce several of the topics covered in a stoichiometry unit. Most of these lessons were made possible by great teachers who shared their own resources. We need your help to keep the collection growing. Do you have a great demonstration, activity, or lesson related to this topic that you would like to share with the community? Please send it along for consideration.