Teacher resources and professional development across the curriculum

Teacher professional development and classroom resources across the curriculum

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Unit 3: Atoms and Light—Exploring Atomic and Electronic Structure


Unit Overview

Using light as a probe, scientists found innovative ways to make inferences about the inner structure of the atom. In this unit, we will follow the gradual change from considering the atom as a single indivisible particle to a later understanding of the atom composed of its constituent subatomic parts, including the electron, the first subatomic particle to be discovered, the proton, and the neutron. This new picture of matter lead to the development of the quantum model of the atom, as well as ways to identify traces of chemical elements, whether on Earth, in the Sun, or in a distant galaxy.

by Louisa Morrison

Louisa Morrison


  1. Introduction
  2. The Electron
  3. The Nucleus
  4. Inside the Nucleus—Protons and Neutrons
  5. The Electromagnetic Spectrum
  6. Light from Elements
  7. The Spectral Lines of Hydrogen
  8. Photoelectric Effect
  9. The Quantum Model
  10. Conclusion
  11. Further Reading

Download Unit 3 Online Text


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