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Interactive
University of Colorado

University of Colorado: Ph Et Interactive Simulations: Atomic Interactions

For Students 9th - 10th
Explore the interactions between various combinations of two atoms. Observe the the total force acting on the atoms or the individual attractive and repulsive forces. Customize the attraction to see how changing the atomic diameter and...
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Article
Khan Academy

Khan Academy: Biology: Chemistry of Life: Matter, Elements, and Atoms

For Students 9th - 10th
Did you know matter is made up of atoms? In this article learn about the smallest unit of matter called the atom.
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Unit Plan
Texas Education Agency

Texas Gateway: Introducing the Atom

For Students 9th - 10th
Get an introduction to the atom in this tutorial.
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PPT
Sophia Learning

Sophia: Atomic Number

For Students 9th - 10th
Learn what atomic number is, and what happens if the numbers of protons in an atom changes.