Chemical Reactions & Energy
In our next unit, students explore how chemical reactions can be used to solve real-world problems. The central challenge asks students to think about how food could be heated when common methods—such as electricity or flames—are not available. This question provides the context for investigating both science concepts and engineering decision-making.
Students begin by observing a real example of a device that heats food without a flame. From there, they develop initial ideas about what might be happening at the particle level and identify questions they need to answer before attempting their own designs. Along the way, they practice modeling systems and tracking where energy is transferred.
Next, students carry out investigations to determine whether different chemical processes release or absorb energy. They collect temperature data, compare outcomes across multiple reactions, and use evidence to decide which reactions are most effective for their purpose. These activities build an understanding of how energy transfer depends on both the substances involved and the amounts used.
With this scientific foundation, students shift into an engineering phase. They define criteria and constraints for a workable solution, including effectiveness, efficiency, and practicality. Students then design, test, and revise prototypes, using data and peer feedback to guide improvements.
As the unit progresses, students compare designs, consider trade-offs, and think about how changes to one part of a system can affect others. This emphasizes the iterative nature of engineering and the importance of evaluating unintended consequences and stakeholder needs.
The unit concludes with students applying what they have learned to evaluate competing solutions in a new context. Throughout the unit, students practice scientific reasoning, data analysis, collaboration, and evidence-based decision-making while deepening their understanding of chemical reactions and energy transfer
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