Lesson Plan

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Lesson Plan
Grade: Date: 17/01/2026
Subject: Chemistry
Lesson Topic: State the conditions required for the rusting of iron and steel to form hydrated iron(III) oxide
Learning Objective/s:
  • Describe the four essential conditions for rust formation on iron and steel.
  • Explain how moisture and electrolytes facilitate the electro‑chemical reaction.
  • Analyse how variations in pH, temperature, and salt concentration affect the rate of rusting.
  • Evaluate strategies to prevent rust by removing one or more required conditions.
Materials Needed:
  • Projector or interactive whiteboard
  • Slide deck with reaction diagrams
  • Sample iron nail or steel strip
  • Small tray with water and salt solution
  • Worksheet with fill‑in tables
  • Safety goggles
 Introduction:
Begin with a quick demonstration: a clean nail left in a damp container begins to develop a reddish coating. Ask students what they know about why metal corrodes, linking to prior lessons on oxidation‑reduction. State that by the end of the lesson they will be able to list all conditions needed for rust to form and predict how changes in the environment influence the process.
Lesson Structure:
  1. Do‑now (5'): Students write down everyday examples of rust they have seen; collect responses.
  2. Mini‑lecture (10'): Present the four conditions using slides and an electrochemical cell diagram.
  3. Guided investigation (15'): In groups, place iron nails in water with/without salt, observe colour change over 5‑10 minutes, and record observations.
  4. Concept check (10'): Whole‑class discussion linking observations to required conditions; teacher uses click‑questions.
  5. Application activity (10'): Worksheet where pupils predict rust rate under different scenarios (e.g., sea air vs. dry climate) and suggest preventive measures.
Conclusion:
Summarise that rust requires iron, oxygen, water, and an electrolyte, and that altering any of these can slow corrosion. Have students complete an exit ticket: name one condition and a practical way to control it. Assign a short homework to research a real‑world anti‑rust coating and write a brief description.