Lesson Plan

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Lesson Plan
Grade: Date: 25/02/2026
Subject: Chemistry
Lesson Topic: State that: (a) Group VIII noble gases have a full outer shell (b) the number of outer shell electrons is equal to the group number in Groups I to VII (c) the number of occupied electron shells is equal to the period number
Learning Objective/s:
  • State that Group VIII noble gases possess a completely filled outer electron shell.
  • Explain why the number of valence electrons equals the group number for Groups I–VII.
  • Relate the period number to the number of occupied electron shells in an element.
  • Apply the 2n² rule to determine the maximum electrons a shell can hold.
Materials Needed:
  • Projector or interactive whiteboard
  • Large periodic‑table poster
  • Worksheet with element tables
  • Coloured markers and chart paper
  • Printed handout of the 2n² rule
  • Exit‑ticket slips
 Introduction:

Begin with the question “Why don’t noble gases react?” to spark curiosity. Review students’ prior knowledge of valence electrons and the layout of the periodic table. Explain that today they will be able to state three predictable patterns that link group and period numbers to electron arrangements.
Lesson Structure:
  1. Do‑now (5'): Quick quiz on group numbers and valence electrons.
  2. Mini‑lecture (10'): Present the three rules – Group VIII full shell, group‑valence relationship, period‑shell relationship; introduce the 2n² formula.
  3. Guided practice (10'): Students fill a table for selected elements (He, Ne, Na, Cl, Mg, S) showing group, valence electrons, period, and shells.
  4. Demonstration (5'): Highlight groups and periods on the poster, using arrows to illustrate the patterns.
  5. Collaborative activity (10'): In pairs, create a mini‑poster linking a chosen element to its group number, valence electrons, and occupied shells.
  6. Check for understanding (5'): Exit ticket – “State the three rules in your own words.”
Conclusion:

Recap the three key relationships and confirm understanding through the exit tickets. Assign homework: complete the worksheet that asks students to predict electron configurations for a set of elements using the rules learned.