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What is Fission?

To demonstrate the concept of nuclear fission and its resulting burst of energy to younger students.

Grade Level:
Middle school and elementary

Time Required:
Five to ten minutes



  1. The teacher will blow up the balloon and tie it closed. (Leave a small amount of room for expansion.) Explain that this balloon represents an atom of uranium.
  2. Twist the balloon in the center to make two separate air chambers. Hold it with two hands, pinching off both chambers with the fingers.
  3. Have a student cut the balloon between the two chambers, making two separate balloons. Explain that this is fission, the splitting of one atom into two atoms of smaller size.
  4. Let both the pieces go. As they fly away explain that this is like the energy released during fission.
  5. Retrieve both pieces. Ask if these pieces are useful anymore (no, they are not). Explain that these pieces are now like nuclear waste.

Analysis and Results:
Students must write down observations about what the teacher is doing with the balloon as the activity proceeds.


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