What is fission?
- The splitting of a large, unstable nucleus into two smaller nuclei
- Releases a huge amount of energy
- Also releases 2-3 neutrons
- Used in nuclear power stations and nuclear weapons
Fission of Uranium-235:
Neutron → ²³⁵U → ⁹²Kr + ¹⁴¹Ba + 3 neutrons + ENERGY
○ → ⬤ → ● + ● + ○○○ + ⚡⚡⚡
The process:
- A slow neutron is absorbed by a uranium-235 nucleus
- The nucleus becomes unstable
- It splits into two smaller nuclei (fission products)
- 2-3 neutrons are released
- A huge amount of energy is released
This key facts covers Nuclear Fission — Key Details within Nuclear Fission & Fusion for GCSE Physics. Revise Nuclear Fission & Fusion in Atomic Structure for GCSE Physics with 13 exam-style questions and 25 flashcards. This topic appears less often, but it can still be a useful differentiator on mixed-topic papers. It is section 5 of 18 in this topic. Use this key facts to connect the idea to the wider topic before moving on to questions and flashcards.
Practice questions for Nuclear Fission & Fusion
What is nuclear fission?
Explain what is meant by a chain reaction in nuclear fission.
Quick recall flashcards
What is nuclear fusion?
The joining of two small, light nuclei to form a larger nucleus, releasing energy
What is nuclear fission?
The splitting of a large, unstable nucleus into two smaller nuclei, releasing energy and neutrons