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Electron Configuration and the Periodic Table (89 Favorites)

ACTIVITY in Periodic Table, Electron Configuration, Valence Electrons, Electrons, Orbitals . Last updated December 17, 2021.


Summary

In this activity, students will learn how the periodic table can be used to predict the electron configuration of an atom and, thus, better predict the reactivity of an atom.

Grade Level

High School

NGSS Alignment

This activity will help prepare your students to meet the performance expectations in the following standards:

  • HS-PS1-1: Use the periodic table as a model to predict the relative properties of elements based on the patterns of electrons in the outermost energy level of atoms. 

Objectives

By the end of this activity, students should be able to:

  • Write the electron configuration of an atom using the Aufbau Principle.
  • Correlate the valence orbital of an atom with the atom’s placement on the periodic table.
  • Predict the relative reactivity of an atom based on its electron configuration and placement on the periodic table.

Chemistry Topics

This activity supports students’ understanding of

  • Electron Configurations
  • The Periodic Table
  • Aufbau Principle
  • Valence electrons
  • Electron orbitals
  • Subatomic Particles

Time

Teacher Preparation: minimal

Lesson: 45-60 minutes

Materials

  • Periodic table, 1 per student
  • Post-it notes, 1 per student
  • Markers
  • Large wall-sized periodic table
  • List of 20 atoms

Teacher Notes

  • A lesson on writing electron configurations should precede this lesson. This could involve writing configurations in order of orbitals with the aid of an Aufbau chart (see sidebar for a chart through 5p). Once students get the hang of that, this activity will help them recognize how patterns in electron configuration line up with the layout of the periodic table – and that is in fact why the periodic table has its strange shape!
  • This lesson involves individual work to practice writing electron configurations, pair work to check electron configurations, and a culminating class activity.
  • Students will be instructed and will practice writing electron configurations for 20 carefully chosen atoms: H, Xe, Rb, Fe, Si, I, Hg, Ra, Mg, Eu, Zn, Ta, Ba, N, S, Co, He, Am, Y, Pd.
  • It is suggested that lower performing students should be assigned the shorter configurations only (ex: those in the first 3 periods, before the d-block, or those in the first 5 periods, before the f-block) and higher performing students should be assigned all 20 atom configurations.
  • Direct students to check their configurations with their shoulder partner and resolve any discrepancies in their answers.
  • You will randomly assign each student one atom and from the list of assigned atoms. Students will write the valence shell in large print, with a marker on their post-it note (ex. 4s2).
  • The student will place the post-it note on the corresponding element symbol on the large wall-sized periodic table. Students will then study the chart with the post-it-notes and observe any noted trends, relationships to groups and periods, with classmates.
  • You could follow up this activity with a fun game of E-config Battleship for more practice with electron configurations!

    For the Student

    Pre-activity Questions

    1. What is the Aufbau Principle?
    2. How is bonding related to electron configuration?

    Objective

    You will learn how the periodic table can be used to determine the electron configuration of an atom and predict the reactivity of an atom based on its configuration and placement on the periodic table.

    Procedure

    1. In the table below, write the electron configurations of the following atoms using the Aufbau principle according to your teacher’s instruction: H, Xe, Rb, Fe, Si, I, Hg, Ra, Mg, Eu, Zn, Ta, Ba, N, S, Co, He, Am, Y, Pd.
    2. Check your electron configurations for accuracy with your shoulder partner.
    3. For your assigned atom, write largely and legibly the valence shell configuration on a post-it note. Place the post-it note on top of your assigned atom on the periodic chart on the wall.
    4. Make note of your observations of patterns on the chart indicated by the post-it notes and placement on the chart. Consider changes as you go up and down the periodic table or left to right on the periodic table in the total electrons, valence electrons, energy levels, periods, sublevels, blocks, and groups/families.
    5. Complete analysis questions.
    6. Prepare to discuss findings and explain trends to the class.

    Data

    Element Symbol

    Electron Configuration

    H

    Xe

    Rb

    Fe

    Si

    I

    Hg

    Ra

    Mg

    Eu

    Zn

    Ta

    Ba

    N

    S

    Co

    He

    Am

    Y

    Pd

    Analysis

    1. What trends do you see when considering total electrons, valence electrons, energy levels, periods, sublevels, blocks, and groups/families.
    2. Explain how you can determine the electron configuration of an atom simply by looking at the periodic table.
    3. What is the connection between the patterns you observed and the historical reasons for grouping elements in families?
    4. Why is the periodic table shaped the way it is?
    5. Which electron configurations are the most stable configurations? Why?
    6. The most common reaction pattern for transition elements (d block) is losing two electrons. What does this fact suggest about how these elements lose electrons? A few sample electron configurations may be useful to reference in your answer.

    Conclusion

    Summarize your findings in your own words. In your summary, include your explanation for how you think the electron configuration of an atom is related to its reactivity.