Unpacked Content
Scientific and Engineering Practices
Constructing Explanations and Designing Solutions
Crosscutting Concepts
Energy and Matter
Knowledge
Students know:
- Engineering is a systematic and often iterative approach to designing objects, processes, and systems to meet human needs and wants.
- The Engineering Design Process (EDP) is a series of steps engineers use to guide them as they solve problems.
- The EDP may include the following cyclical steps: ask, imagine, plan, create, and improve.
- In chemical reactions, the atoms that make up the original substances are regrouped into new substances with different properties.
- Chemical reactions can release thermal energy or store thermal energy. Criteria are requirements for successful designs.
Skills
Students are able to:
- Design and construct a solution to a problem that requires either heating or cooling.
- Describe the given criteria and constraints.
- Test the solution for its ability to solve the problem via the release or absorption of thermal energy to or from the system.
- Use the results of the tests to systematically determine how well the design solution meets the criteria and constraints, and which characteristics of the design solution performed the best.
- Modify the design of the device based on the results of iterative testing, and improve the design relative to the criteria and constraints.
Understanding
Students understand that:
- Some chemical reactions release energy, others store energy.
- The transfer of energy can be measured as energy flows through a designed or natural system.
- A solution needs to be tested, and then modified on the basis of the test results, in order to improve it.
- Although one design may not perform the best across all tests, identifying the characteristics of the design that performed the best in each test can provide useful information for the redesign process - that is, some of the characteristics may be incorporated into the new design.
- The iterative process of testing the most promising solutions and modifying what is proposed on the basis of the test results leads to greater refinement and ultimately to an optimal solution.
Vocabulary
- Design
- Construct
- Test
- Modify
- Device (e.g., glow stick, hand warmer, hot or cold pack, thermal wrap)
- Engineering
- Engineering Design
- Process
- Temperature
- Exothermic (release thermal energy)
- Endothermic (absorb thermal energy
- Thermal energy
- Chemical reactions (e.g., dissolving calcium chloride in water)
- Criteria (e.g., amount/concentration, time, temperature)
