The Period Table/Periodic Chemistry

Grade 10 · Chemistry

Semester 1 | Period 3 | Week 13

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Subject: Chemistry

Semester: 1

Period: 3

Week: 13

School Name:
Teacher’s Name:
Subject: Chemistry
Grade Level: Grade 10
Week & Period: Weeks 13, Period III
Date:
Topic: The Periodic Table / Periodic Chemistry
Topic: History & Origin of The Periodic Law

  • Discuss history and development of the periodic table
  • Identify that elements are placed on the periodic table due to similar properties

 

Learning Objectives:

  • Discuss the history and development of the periodic table
  • Identify that elements are placed on the periodic table due to similar properties
  • Describe the origin of the periodic law

Previous Knowledge:
Learners understand basic atomic structure and element properties.

Instructional Materials:

  • Periodic table copies (modern and old versions)
  • Timeline chart of periodic table development
  • Biographical cards for key scientists (Mendeleev, Moseley)

Anticipation (Warm-Up) – 5 minutes
Ask:

  • "Why do you think scientists tried to organize elements in a table?"
  • "What problems might arise if elements were listed randomly?"

Building Knowledge (Main Lesson) – 25 minutes

  1. History & Origin of the Periodic Law
    • Early attempts to classify elements
    • Mendeleev’s periodic table and prediction of elements
    • Moseley’s contribution: atomic number as organizing principle
  2. Importance of periodic law for chemistry

Learners’ Activities:

  • Discuss in pairs the advantages of having a periodic table
  • Create a timeline of major discoveries related to the periodic table
  • Answer oral questions about key figures

Consolidation (Review & Assessment) – 10 minutes
Questions:

  • Who created the first periodic table?
  • What is the periodic law?
  • How did Moseley improve the periodic table?

Homework / Assignment:

  • Write a short paragraph summarizing the history of the periodic table
  • Prepare a list of 5 elements with their atomic numbers and symbols

Notes – Detailed and Explained:

  • The periodic law states that properties of elements are a periodic function of their atomic numbers.
  • Mendeleev arranged elements by increasing atomic mass but left gaps for undiscovered elements.
  • Moseley’s work led to arranging elements by atomic number, correcting earlier inconsistencies.
  • The periodic table helps predict properties of elements yet to be discovered.

Expanded Notes / Instructions:

  • Use visual timelines to help learners connect historical events.
  • Relate discoveries to modern science and technology benefits.
  • Provide extra help with difficult vocabulary like “periodic,” “atomic number,” and “properties.”

Inclusive / Differentiation:

  • Use stories and role-play about scientists for kinesthetic learners.
  • Encourage peer discussion and presentations.
  • Provide summary notes and diagrams for learners needing extra support.

Teacher’s Reflection:

  • Did learners understand the importance of organizing elements?
  • Were learners able to identify key scientists and their contributions?
  • Did the timeline activity engage learners of different abilities?