Improve a cooling reaction device

Can a safe open-container design meet a cooling target?

Submit: Approved plan, timed trial table, energy model and tested redesign.

Related lesson: Chemical Reactions

This is a teacher-led extension beyond the short lesson. The task supplies a performance opportunity; completion alone does not certify mastery, full NGSS coverage or state alignment.

Build the idea

Some chemical processes absorb thermal energy from their surroundings. A cooling design must meet a stated temperature-change goal while using limited material. A temperature decrease is evidence of energy transfer, not disappearance of energy. Reaction mixtures may release gas and must stay open.

Evidence and model inputs

Design goal: an adult-approved baking-soda and vinegar mixture cools by at least 2 °C within two minutes using at most 50 mL vinegar and 5 g baking soda. These are design constraints, not guaranteed results. Measure the actual starting and minimum temperatures; if the goal is not met, explain the limitation honestly.

Keep actual observations, published findings and invented model cases labeled separately. If a source or required equipment is unavailable, pause that part with a teacher; do not invent results.

Materials and preparation

Adult-provided vinegar, baking soda, open plastic cups, tray, thermometer, timer, measure and eye protection.

Grade-level scope

Teacher-supervised small-scale household chemistry only. No tasting, skin application or sealed gas-producing devices.

Do the work

1. Teacher approves an open plastic cup in a spill tray, eye protection and small quantities of household materials. Never seal or taste the mixture.
2. Record room and liquid temperatures; predict the direction of thermal energy transfer.
3. Test one permitted starting recipe and record temperature every 20 seconds for two minutes.
4. Change one factor, such as baking-soda amount, within the limits. Keep the cup and measurement procedure consistent; repeat trials.
5. Compare cooling, timing and material use; revise and test the design or document why it fails the goal.

Learner worksheet

Write on paper or type here and print. Entries stay in this page’s memory and are lost when you leave or reload; they are not saved or submitted.

Check your reasoning

1. Where does absorbed energy come from?
2. Why never seal the cup?
3. Is fizzing alone a cooling measurement?
4. What if the goal fails?

Teacher review guide

Review the actual deliverable and discuss the reasoning. For each criterion, use 0 when evidence is absent or fundamentally incorrect, 1 when partly supported with a material error or omission, and 2 when accurate, supported and complete for the stated task. Maximum 8 points is a task score, not a proficiency certification. Give feedback and allow revision.

1. States quantitative criteria and material constraints.
2. Collects timed temperature data under controlled conditions.
3. Explains energy transfer consistently with cooling.
4. Tests a justified revision and evaluates the goal.

Sources and standard reference

• Official NGSS MS-PS1-6 performance expectation — inspect the practice, core idea, crosscutting concept and assessment boundary.

Instructional text and hypothetical cases are original. Linked source readings supply published evidence where specified. Teachers should judge fit with their course and state requirements.