O-Level Chemistry Planning & Risk Statement Library

TL;DR
Planning contributes 15 % of Paper 3. SEAB expects candidates to identify variables, outline procedures, reference safety, and explain data handling (SEAB 2026 syllabus, pp. 25–27).
This library groups ready-to-use statements by experiment family — titration, rates, separation, salt prep, gas collection, qualitative inorganic/organic, and data-logger tasks — so you can mix-and-match during the exam.
Pair it with the ACE Evaluation Clinic to deliver a full-score P–MMO–PDO–ACE response.

1 | Planning checklist (use for every task)

1. Aim / hypothesis — what you are measuring or proving.
2. Variables — independent, dependent, and at least two controls with how to keep them constant.
3. Apparatus & method — concise steps referencing the official apparatus list (p. 28).
4. Safety — chemicals, equipment, PPE, waste disposal.
5. Data handling — how measurements will be recorded, averaged, or graphed.
6. Validity — repeat runs, concordant readings, or reference samples/control tests.

Write in full sentences but keep it tight; aim for 6–8 bullet points or short paragraphs.

2 | Statement bank by experiment family

Titration

• Aim. “To determine the concentration of ___ acid by titrating with 0.100 mol dm⁻³ NaOH.”
• Variables. Keep temperature constant (lab ambient), use the same indicator volume (3 drops phenolphthalein).
• Safety. Acids/alkalis are corrosive — wear goggles, rinse spills with water.
• Data. Record initial/final burette readings to 0.05 cm³; average concordant titres within 0.10 cm³.

Rates of reaction

• Aim. “To investigate how acid concentration affects the rate of CO₂ production from marble chips.”
• Variables. Keep chip mass and surface area constant, maintain temperature with water bath.
• Safety. CO₂ displaces oxygen — conduct in ventilated area; acids corrosive.
• Data. Measure gas volume every 20 s using gas syringe; plot volume vs time.

Thermochemistry / calorimetry

• Aim. “To determine the temperature change when metal X reacts with dilute acid.”
• Variables. Use same acid volume/concentration; insulate polystyrene cup with lid.