Physical Science 14

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Atoms are the basic unit of a chemical element. An atom a fundamental piece of matter. (Matter is anything that can be touched physically.) Everything in the universe (except energy) is made of matter, and, so, everything in the universe is made of atoms.


Day 1 – Introduction
Day 2 – Virtual Textbook


5:27 Just How Small is an Atom?

8:43 What Does An Atom REALLY Look Like?

0:48 First Picture of the Hydrogen Atom



Atoms are obviously very small. Atoms are a bit difficult to understand. Prior to the year 2000, atoms were often represented with simple illustrations showing electrons circling around protons and neutrons.

Today though, we know about the “electron cloud” – and the simple illustrations are not entirely accurate. Some people think the simple illustrations are still a great way to teach young people about atoms. Others think that even though the general concepts can be taught with the simpler illustrations, it is better to use a more accurate description even if it is complicated and difficult to draw.

  • Position A: The “old-school” illustrations of atoms remain a great way to teach about atoms.
  • Position B: Accuracy is more important than simplicity in teaching about atoms. The “old-school” illustrations should be abandoned.

Instructor Resources

Standard Daily Material
  • Day 1 – Standard material – introduction day
  • Day 2 – Standard material – reading day
  • Day 3 – Standard material – make a presentation
  • Day 4 – Standard material – give a presentation
  • Extra! – Enrichment and remediation options
Other Topic Specific Resources

Special Notes

Instructor Emphasis:

  • Science & Engineering Practice: Develop and use models.
  • Cross-Cutting Concept: Structure and Function.