OpenSciEd 7.2, Lesson 4: Proportions of Reactants Investigation (Vernier Powered, Guided)
Task
Use this Vernier-Powered Tuva Investigation with the Grade 7 OpenSciEd curriculum during Unit 7.2, Lesson 4. Tuva has digitized the Analyzing Our Data Collection Methods handout, the Investigation Procedure for Proportion of Reactants handout, and the Small-Group Data Table, provided in Parts 2–5. Students collect their time and temperature data with a Vernier Go Direct Temperature Probe and use the Tuva Tools to create data visualizations that help them make sense of it and respond to questions. Each group will need a Go Direct Temperature Probe and a computer running Chrome or Edge, the two browsers that can connect to the probe. The probe takes the place of the digital thermometer listed on each group's tray in the OpenSciEd materials list. Tuva is used to deepen data sensemaking; it is not a standalone lesson. Use it in tandem with the OpenSciEd Teacher Edition. Where This Investigation Fits into the Storyline Last lesson, students found that copper sulfate and aluminum foil in saltwater gave the greatest temperature increase. This lesson, students test different proportions of those two reactants to find which one heats food best. When to Use Tuva Day One Before opening Tuva, complete Part 1's navigation discussion. (Use page 8 of the Teacher Edition). Also complete the first two sub-sections of Part 2, the Turn and Talk About Systematic Testing and the Discussion About Different Amounts of Each Reactant to Try. (Use page 10 of the Teacher Edition.) Then, have students pull up Tuva for the rest of Part 2. In Steps 1 to 3 students will evaluate the procedure and record their evaluations in Tuva. You may want to evaluate the first portion of the procedure as a class and/or have students share out after they evaluation the other portions. (Use pages 11–13 of the Teacher Edition for guidance.) Review safety instructions in Step 4, then complete Part 3 using Tuva. Students record their group's assigned amounts in Step 5, connect the probe in Step 6, measure the reactants in Step 7, make their five-minute run in Step 8, examine the solids and liquids in Step 9, graph their data in Step 10, and find their temperature change in Step 11. Note: Readings collected with the probe are held in the browser and are lost if the page is reloaded, so plan for each group to work through Steps 6 to 11 — connecting the probe, measuring the reactants, the five-minute run, filtering the mixture, the graph, and the temperature change — in one sitting. The temperature change each group types in Step 11 is saved with their work, so that is a safe place to break for the day if you do not have time for the exit ticket. Part 4, the Exit Ticket, is Step 12 and will be submitted on Tuva as well. Day Two Before beginning Part 5, the Building Understandings Discussion, have students return to Tuva. Share the class data table. In Step 13 students will take a few moments to enter the class data into a digital table, and in Step 14 they will explore it visually and record their initial ideas about possible claims and evidence using those graphs. Students can bring their Tuva graphs and their initial ideas to Part 5, the Building Understandings Discussion. (Use pages 16–18 of the Teacher Edition to facilitate.) What Happens Next The remainder of the lesson, Parts 6–7 will happen offline. Use the Teacher Edition for guidance.
Last time, we tested different chemical reactions and figured out that root killer (CuSO^^4^^) and aluminum foil (Al). We figured out that mixing copper sulfate and aluminum foil together transferred a lot of energy out of the reaction system and decided to use those reactants for our flameless heaters. In the previous investigation, we used equal amounts of root killer (copper sulfate) and aluminum. | Aluminum (g) | CuSO₄ (g) | Total grams of reactants | Avg. temp change (°C) | | :--- | :--- | :--- | :--- | | 3 | 3 | 6 | 35 | But are equal proportions of reactants the best combination to use? What if we combine different amounts of each reactant? In this investigation, we will be answering: How much of each reactant should we include in our homemade flameless heater? Click Next to get started.
Topics and standards: MS-ETS1-2, MS-ETS1-3, Engineering & Design, Grade 7, MS-PS1-6, OpenSciEd, 3.2.6-8.F