#93
4.4.2.4 The pH scale and neutralisation
Paper 1 · Higher combined
Spec reference: 4.4.2.4 (under 4.4.2).
What you need to know
- (Key facts / definitions / equations for this spec point)
Support videos
- FreeScienceLessons (topic playlist): (use links below)
- FreeScienceLessons (Chemical changes playlist): https://www.youtube.com/playlist?list=PL9IouNCPbCxXDlRtCQEG0cGehBvJ7t9Pf
Self-assessment (checklist)
- I can state the type of ion produced by acids in aqueous
- I can state the type of ion found in aqueous solutions of
- I can describe what the pH scale shows.
- I can describe how the pH of a solution can be
- I can state the pH of neutral solutions.
- I can describe where acidic solutions are found on the
- I can describe where alkaline solutions are found on the
- I can use the pH scale to identify acidic or alkaline
- I can describe how to carry out titrations using strong
Key steps (method)
- Identify what the question is testing and use precise chemistry vocabulary.
- If it’s a calculation: write the equation/formula first, then substitute carefully.
Common mistakes
- Missing units/state symbols when asked.
- Giving a statement without linking cause → effect.
Exam-style questions (quick)
- Define the key term(s) for this point in the spec.
- Explain a typical property/result using particle/bonding ideas.
- Do a short calculation or interpretation step relevant to this point.
Practice questions
- PMT: Chemical changes (questions + notes): https://www.physicsandmathstutor.com/chemistry-revision/gcse-aqa/chemical-changes/
Extra knowledge organisers
- Extra KO (Chemical changes) — Buckingham School PDF: https://www.buckinghamschool.org/_site/data/files/files/ko-science/gcse-sep/chem/AQASSC4ChemicalChanges.pdf