Lesson Plan

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Lesson Plan
Grade: Date: 17/01/2026
Subject: Chemistry
Lesson Topic: Classify $mathrm{Al}_2 mathrm{O}_3$ and $mathrm{ZnO}$ as amphoteric oxides
Learning Objective/s:
  • Describe the definition of an amphoteric oxide.
  • Explain the reactions of Al₂O₃ and ZnO with acids and with bases, including balanced equations.
  • Predict the products formed when these oxides react with strong acids or bases.
  • Compare the properties of Al₂O₃ and ZnO that enable amphoteric behavior.
  • Apply knowledge to solve typical exam questions on amphoteric oxides.
Materials Needed:
  • Projector or interactive whiteboard
  • Chemistry textbook or teacher notes
  • Worksheet with reaction equations
  • Molecular model kits (Al₂O₃ and ZnO)
  • Whiteboard and markers
  • Exit ticket cards
 Introduction:
Begin with a quick demonstration: drop a small amount of Al₂O₃ into hydrochloric acid and observe fizzing, then show ZnO dissolving in sodium hydroxide. Review students’ prior knowledge of acid‑base reactions and oxide classification. State that by the end of the lesson they will be able to classify these oxides as amphoteric and write their reactions with acids and bases.
Lesson Structure:
  1. Do‑now (5') – short quiz on acid‑base definitions and identification of amphoteric oxides; teacher reviews answers.
  2. Mini‑lecture (10') – define amphoteric oxides, present key properties of Al₂O₃ and ZnO, display the comparison table.
  3. Guided practice (12') – work through balanced equations for reactions with HCl and NaOH using the worksheet; teacher circulates.
  4. Hands‑on demonstration (8') – show the two reactions (or video), ask students to predict products before each demonstration.
  5. Formative check (5') – exit ticket where students write one acid reaction and one base reaction for each oxide.
Conclusion:
Summarise that Al₂O₃ and ZnO react both as acids and bases, producing salts with acids and complex hydroxide ions with bases. Ask students to exchange exit tickets and reflect on the key indicators of amphoteric behavior. Assign homework to complete a set of practice questions on classifying oxides and writing balanced equations.