"Explain" questions — WJEC A-Level Chemistry (Wales)
113 questions · chemistry · View as Markdown
How to answer
WHAT + WHY. Every point paired with a because. Structure: X happens because Y. This causes Z because … Assessment Objective: AO2. Every "explain" answer on this spec is marked against exactly this pattern.
Sample questions
- Sodium and potassium are both elements in Group 1 of the periodic table. When a small piece of potassium is placed on co…
- A pharmacist is checking whether a batch of a pain-relief tablet is a pure compound or a mixture. She dissolves a small …
- Cyclohexene and benzene are both cyclic hydrocarbons with the molecular formula suggesting multiple carbon–carbon bonds.…
- A student carries out oxidation reactions on two unknown organic compounds, X and Y. Compound X is oxidised by acidified…
- Ethanoic acid is a carboxylic acid. Explain what happens when ethanoic acid is added to sodium carbonate solution, and d…
- A technician is investigating three paint samples — paint P, paint Q and paint R. He carries out paper chromatography on…
- Chlorine has two naturally occurring isotopes: chlorine-35 and chlorine-37. Explain what is meant by the term isotope an…
- Propane (C₃H₈) is a hydrocarbon used as a fuel in camping stoves. When propane burns completely in oxygen, the products …