Organic Chemistry & Material Design — Extension · Physical Science: Chemistry, Grade 11
Use carbon structure, polymer properties, and life-cycle evidence to evaluate materials.
Polymer-Use Design Decision
Investigate
When does reuse improve a modeled material impact?
Use two dedicated sessions: first define the model, boundary, variables and comparison, then collect suitable records or analyze the complete supplied-data route; second complete calculations/graphs, compare alternatives, revise and prepare the report. Extend collection time where needed. Supplied-data work does not certify supervised laboratory minutes or mandated investigations.
Materials
- Provided material-impact table
- Calculator andpaper molecular models
Before you begin
Use only the listed household materials or analyze the supplied data. An adult should review setup. No flames, strong acids/alkalis, unknown chemicals, household mains, radiation sources, or high-speed projectiles are needed. Keep food-study materials separate from eating and wash hands afterward.
Plan a fair test
Compare equal drink-serving function; include production plus use-stage impact and vary use count.
Method
- Write a prediction and the physical/chemical mechanism behind it.
- Draw the setup or system boundary; label variables and units.
- Sketch an addition-polymer repeat unit and explain structure-property links.
- Calculate total impact at 10,50,and 100 uses.
- Test a shorter lifespan or higher washing impact and revise the recommendation.
- Record repeated observations where possible; keep original readings and note resolution or uncertainty.
- Write a claim supported by specific numbers, explain the mechanism, and identify one limitation and a next test.
Example data — for analysis when materials are unavailable
Illustrative teaching data, not measurements from a real district laboratory. Analyze these when materials are unavailable and identify them as provided data. Do not claim to have performed a measurement you did not make.
| Option | Production impact(units) | Per-use impact(units) |
|---|---|---|
| Disposable | 0 | 10 |
| Reusable A | 500 | 2 |
| Reusable B | 300 | 4 |
Analyze and explain
- Find modeled break-even use count for each reusable option.
- Which has least impact at 100 uses?
- Which omitted effects could change your choice?
- Link the pattern to a labeled particle, structure, energy or amount model from the chapter.
- Distinguish supplied illustrative records from measurements actually collected.
- Identify uncertainty and propose a comparison that would test an alternative explanation.
What a strong explanation includes
- A stated prediction, conditions, and controlled variables or explicit model boundary.
- A labeled table/graph with units, calculations, and attention to repeated values or uncertainty.
- A claim citing numerical evidence and a scientifically accurate mechanism.
- A limitation, alternative explanation, and useful follow-up test.
- Preserve initial reasoning and an evidence-supported revision.
- Check units, species identity, system boundary and physical assumptions.
Parent / teacher guide: discuss after the investigation
A equals disposable at 62.5 uses andB at 50 uses. At 100 uses, totals are 1000,700,700 units. Reuse advantage depends on actual lifespan and washing; contamination, local recovery, and other impacts need evaluation before a broad claim. Preserve the original observations, intermediate working and a labeled mechanism. Report the relevant boundary and model assumptions, discuss an alternative explanation, and identify the next useful measurement; do not replace unexpected data with the illustrative record.
Compare this model with the learner’s actual evidence. Different measurements can support a different conclusion; check the reasoning and limitations, not matching wording.
Extend the chapter investigation by evaluating its evidence and proposing a better test.
Problem 1
Answer and explanation
A equals disposable at 62.5 uses andB at 50 uses. At 100 uses, totals are 1000,700,700 units. Reuse advantage depends on actual lifespan and washing; contamination, local recovery, and other impacts need evaluation before a broad claim. Preserve the original observations, intermediate working and a labeled mechanism. Report the relevant boundary and model assumptions, discuss an alternative explanation, and identify the next useful measurement; do not replace unexpected data with the illustrative record.
Problem 2
Answer and explanation
A equals disposable at 62.5 uses andB at 50 uses. At 100 uses, totals are 1000,700,700 units. Reuse advantage depends on actual lifespan and washing; contamination, local recovery, and other impacts need evaluation before a broad claim. Preserve the original observations, intermediate working and a labeled mechanism. Report the relevant boundary and model assumptions, discuss an alternative explanation, and identify the next useful measurement; do not replace unexpected data with the illustrative record.
Problem 3
Answer and explanation
A equals disposable at 62.5 uses andB at 50 uses. At 100 uses, totals are 1000,700,700 units. Reuse advantage depends on actual lifespan and washing; contamination, local recovery, and other impacts need evaluation before a broad claim. Preserve the original observations, intermediate working and a labeled mechanism. Report the relevant boundary and model assumptions, discuss an alternative explanation, and identify the next useful measurement; do not replace unexpected data with the illustrative record.
Problem 4
Answer and explanation
A equals disposable at 62.5 uses andB at 50 uses. At 100 uses, totals are 1000,700,700 units. Reuse advantage depends on actual lifespan and washing; contamination, local recovery, and other impacts need evaluation before a broad claim. Preserve the original observations, intermediate working and a labeled mechanism. Report the relevant boundary and model assumptions, discuss an alternative explanation, and identify the next useful measurement; do not replace unexpected data with the illustrative record.
Problem 5
Answer and explanation
A equals disposable at 62.5 uses andB at 50 uses. At 100 uses, totals are 1000,700,700 units. Reuse advantage depends on actual lifespan and washing; contamination, local recovery, and other impacts need evaluation before a broad claim. Preserve the original observations, intermediate working and a labeled mechanism. Report the relevant boundary and model assumptions, discuss an alternative explanation, and identify the next useful measurement; do not replace unexpected data with the illustrative record.
Problem 6
Answer and explanation
A equals disposable at 62.5 uses andB at 50 uses. At 100 uses, totals are 1000,700,700 units. Reuse advantage depends on actual lifespan and washing; contamination, local recovery, and other impacts need evaluation before a broad claim. Preserve the original observations, intermediate working and a labeled mechanism. Report the relevant boundary and model assumptions, discuss an alternative explanation, and identify the next useful measurement; do not replace unexpected data with the illustrative record.