O-Level Chemistry Observation Language Drill Sheets

TL;DR
Precise observation language is critical for PDO marks—vague phrases lose credit even when deductions are correct.
These drill sheets provide quick-fire prompts to practise describing colours, precipitates, and gas tests using vocabulary consistent with SEAB’s qualitative analysis notes.
Combine the exercises with Planning and ACE reflections to develop habit-forming lab notes.

Anchor to the Experiments Hub

Use these language drills alongside the rest of our O-Level Chemistry Experiments hub so the vocabulary you practise here flows straight into titration, qualitative analysis, and gas-test write-ups.

1 | Why phrasing matters

• SEAB’s qualitative analysis notes include model descriptors (e.g., “light blue precipitate, soluble in excess ammonia to give a dark blue solution”) that you can mirror in your write-ups (SEAB 2026 syllabus, PDF).
• PDO assessment looks for complete, objective statements—colour, state, solubility, gas behaviour—without subjective language.
• Practising phrasing now reduces hesitation when writing under time pressure.

2 | Drill format

For each prompt:

1. Write the observation in one line, including colour, state, and behaviour in excess reagent.
2. Add a follow-up line indicating the likely ion/gas (optional).
3. Time yourself—target 30 s per observation.
4. Review against the suggested answers to tighten phrasing.

3 | Cation observation drills