Class Experiments

Hands-on chemistry labs for the Reactivity Rocket Project

Year 10 Chemistry · Reactivity Rocket Project · Phase 1 Lab Pack

The two laboratory experiments below cover the chemistry that drives the rocket project. Each is a complete lab document — background, hypothesis, materials, method, results template, analysis prompts, discussion structure, and extension questions — designed to be issued to students and used directly as their lab-report scaffold.

Lab 1 — Catalysed Decomposition of Hydrogen Peroxide

H₂O₂ Rates Calibration Phase 1 · primary rates lab

What students do. Build three calibration curves of catalysed H₂O₂ decomposition by varying one parameter at a time:

1. Rate vs [H₂O₂] at 3 % and 6 % drugstore-grade peroxide
2. Rate vs [KMnO₄] at four catalyst concentrations (catalyst saturation)
3. Rate vs T at four temperatures (Arrhenius — activation energy)

The teacher then demonstrates the same reaction at 35 % H₂O₂. Students predict the 35 % rate by extrapolation from their student calibration, then reconcile their prediction against the teacher’s measurement.

Reactions. \(2\text{ H}_2\text{O}_2 \xrightarrow{\text{KMnO}_4} 2\text{ H}_2\text{O} + \text{O}_2\)

Headline output. A stoichiometric worked answer: “At our measured 35 % decomposition rate, can a school-scale rig in principle supply the O₂ for a 0.5 g/min ethanol burn?”

→ Open the lab document   ·   → PDF version (if rendered)

Lab 2 — Calorimetry of Ethanol and Methane Combustion

Ethanol & Methane Calorimetry Phase 1 · synthesis / energy lab

What students do. Burn a known mass of fuel under a 200 mL water bath, measure the temperature rise, and compute the chemical power delivered:

• Mass change of an ethanol spirit burner → \(m_f\)
• Water \(\Delta T\) from K-type thermocouple or thermometer
• \(Q = m_w \cdot c_w \cdot \Delta T\)
• \(P_w = Q / \Delta t\)
• \(\eta = P_w / (m_f \cdot \text{LHV} / \Delta t)\) — combustion efficiency

Repeat for methane (Bunsen, with assumed gas-flow rate). Compare the two fuels on the same rig.

Reactions.

\[\text{C}_2\text{H}_5\text{OH} + 3\text{ O}_2 \to 2\text{ CO}_2 + 3\text{ H}_2\text{O}\]

\[\text{CH}_4 + 2\text{ O}_2 \to \text{CO}_2 + 2\text{ H}_2\text{O}\]

Headline output. Measured energy per gram of fuel — feeds the Computational Engineering team’s prediction sheet for the vendor burn.

→ Open the lab document   ·   → PDF version (if rendered)

How these labs fit the project

Where the data goes student measurement → engineering decision

The two labs together produce the numbers that the rest of the project depends on:

Lab measurement	Used in
H₂O₂ decomposition rate (concentration calibration)	Stoichiometric panel on the comp-eng page
Arrhenius activation energy (T calibration)	Rust crate arrhenius_extrapolate — temperature scaling of vendor catalyst bed
Ethanol energy per gram (calorimetry)	Vendor-burn predicted thrust at 0.5 g/min design point
Combustion efficiency at school scale	Lower bound for the vendor’s pressurised burn

Without the calibration data from the H₂O₂ lab, the rocket project’s stoichiometric claim that “35 % H₂O₂ at ~5.6 mL/min can drive the ethanol burn” is just a textbook calculation. With the calibration, it becomes an experimentally-anchored engineering prediction the Manufacturing team can take to the vendor.

Pedagogical structure (same for both labs)

Each lab follows the standard scientific-report structure:

1. Abstract — what the lab does in one paragraph
2. Introduction — engineering context, background chemistry, theory, hypothesis
3. Materials and equipment — per-group and class lists
4. Safety — risk register references + numbered controls
5. Method — variables table, numbered procedure, risk assessment paragraph
6. Results — raw data tables (empty for student entry), computed-results table
7. Worked example — demonstration numbers showing the calculation
8. Observations — structured prompts for qualitative recording
9. Analysis — formulas, decision rules, calibration-curve plotting guidance
10. Discussion — Claim → Evidence → Reasoning prompts, sources-of-uncertainty cards
11. Conclusion — boxed structured template (3–5 sentences)
12. Extension questions — five harder questions per lab
13. References — including the school laboratory risk-assessment record

Each lab is intended as a single ~90-minute period (or two ~50-minute periods if your school’s timetable splits it). The H₂O₂ lab is the denser of the two because of its three sub-experiments.

Safety summary

Lab	Risk rating	Hardest control
H₂O₂ rates	Medium (35 % H₂O₂ teacher-only)	No organics within 1 m of the 35 % rig
Calorimetry	Low (open flame on water bath)	Cap the ethanol burner immediately after each weighing

Both labs work at standard school concentrations for student handling. 35 % H₂O₂ is dispensed only by the teacher in the H₂O₂ rates lab. See the project safety case for the full risk register and standard operating procedures.