This how it works covers The Four Types of Acid Reactions within Neutralisation Reactions for GCSE Chemistry. Revise Neutralisation Reactions in Chemical Changes for GCSE Chemistry with 20 exam-style questions and 20 flashcards. This topic appears regularly enough that it should still be part of a steady revision cycle. It is section 5 of 13 in this topic. Use this how it works to connect the idea to the wider topic before moving on to questions and flashcards.
⚙️ The Four Types of Acid Reactions
1. Acid + Metal → Salt + Hydrogen
Mg + 2HCl → MgCl₂ + H₂
Fizzing/bubbles seen. Test: squeaky pop with lit splint.
2. Acid + Metal Oxide → Salt + Water
CuO + H₂SO₄ → CuSO₄ + H₂O
Black copper oxide dissolves to give blue solution.
3. Acid + Metal Hydroxide → Salt + Water
HCl + NaOH → NaCl + H₂O
Classic neutralisation — often no visible change.
4. Acid + Metal Carbonate → Salt + Water + CO₂
CaCO₃ + 2HCl → CaCl₂ + H₂O + CO₂
Fizzing/effervescence. Test CO₂: turns limewater cloudy.
Practice questions for Neutralisation Reactions
Which word equation correctly represents a neutralisation reaction?
Explain why the ionic equation for any strong acid-alkali neutralisation is always H⁺(aq) + OH⁻(aq) → H₂O(l).