Physical Science 21

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Nuclear Change

Nuclear change is distinct from chemical change (described in physical science topic 17 on this site). In a nuclear change the elements can change from one to another. An example of this is our own Sun. The Sun generates its energy by nuclear fusion changing hydrogen nuclei into helium. Nuclei can also break apart to form smaller elements (called fission). Nuclei can fuse together to make heavier elements. Neutrons can turn into protons and protons into neutrons.


Day 1 – Introduction
  • Topic 21 – Instructor intro presentation
Day 2 – Virtual Textbook


2:50 Nuclear vs Chemical Reactions

3:19 Nuclear Fusion

3:19 Nuclear 101


The nuclear power debate is a long-running controversy about the risks and benefits of using nuclear reactors to generate electricity for civilian purposes.

Position A: Nuclear powered electric generating plants should become more significant as part of the US electric energy market. Nuclear power is reliable and emission-free.

Position B: Accidents such as the Windscale fire, the Three Mile Island accident, and Chernobyl disaster provide evidence that nuclear plants are too risky. We should cease all efforts to construct more nuclear power capacity.

(Adapted from Wikipedia).

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
  • PS21 Intermolecular forces.tns
  • PS21 Intermolecular forces bellringer.tnsp

Special Notes and Notices

Instructor Emphasis:

  • Science & Engineering Practice: Obtain, evaluate, and communicate information.
  • Cross-Cutting Concept: Stability and Change.