Lesson Plan

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Lesson Plan
Grade: Date: 01/12/2025
Subject: Physics
Lesson Topic: distinguish between nucleon number and proton number
Learning Objective/s:
  • Describe the meaning of proton number (Z) and nucleon number (A) and how they differ.
  • Explain the relationship A = Z + N and identify isotopes using Z and A.
  • Apply the concepts to balance simple nuclear equations and predict changes in Z and A during decay.
Materials Needed:
  • Projector or interactive whiteboard
  • Slides with nucleus diagrams
  • Handout with isotope tables
  • Worksheet with practice problems
  • Colored markers or stickers to represent protons and neutrons
 Introduction:
Begin with a quick visual of a carbon atom model to capture interest. Review that students already know atomic number identifies an element. State that today they will distinguish between proton number and nucleon number and be able to use both when describing isotopes.
Lesson Structure:
  1. Do‑Now (5') – Students label Z and A on a printed nucleus diagram.
  2. Mini‑lecture (10') – Define proton number and nucleon number, show table of differences, introduce A = Z + N.
  3. Guided practice (12') – Work through carbon‑12 and uranium‑235 examples, fill in a worksheet in pairs.
  4. Interactive simulation (8') – Use an online nucleus builder to add/remove neutrons and observe changes in Z and A.
  5. Check for understanding (5') – Quick quiz (Kahoot) on identifying isotopes and predicting decay outcomes.
  6. Summary discussion (5') – Students articulate why the distinction matters in nuclear reactions.
Conclusion:
Recap that proton number defines the element while nucleon number defines the specific isotope. Have students write one exit‑ticket answer describing a decay change in Z and A. Assign homework to complete a worksheet converting nuclear equations.