This memory aid covers Memory Aids within Acids and Alkalis for GCSE Chemistry. Revise Acids and Alkalis in Chemical Changes for GCSE Chemistry with 25 exam-style questions and 21 flashcards. This topic appears less often, but it can still be a useful differentiator on mixed-topic papers. It is section 9 of 12 in this topic. Use it for quick recall, then test yourself straight afterwards so the memory aid becomes usable in an answer.
🧠 Memory Aids
Acids and Alkalis: "HAcids = H⁺ ions. Alkalis = OH⁻ ions." The letter A connects both to their ions.
Indicator colours (three key ones):
- Litmus: Red in acid, Blue in alkali — remember "Red = Acidic, Blue = Alkaline"
- Phenolphthalein: Colourless → Pink in alkali — "Phenol turns Pink in base"
- Methyl orange: Red in acid → Yellow in alkali — "Methyl goes RED when angry (acidic)"
pH scale anchors: 0 = most acidic (stomach acid), 7 = neutral (pure water), 14 = most alkaline (bleach). Everything else falls between these reference points.
The three common acids: "HCl, H₂SO₄, HNO₃" — Hydrochloric, Sulfuric, Nitric. Mnemonic: "Hard Students Never fail" (HCl, H₂SO₄, HNO₃).
Practice questions for Acids and Alkalis
Which ion do acids produce when dissolved in water?
Explain the difference between a strong acid and a concentrated acid.