Science Double Award - 4SD0 PearsonEdexcel

Fission And Fusion

Overview

The energy that powers nuclear reactors and the energy that keeps stars shining come from the same place: the nucleus. Splitting heavy nuclei apart (fission) and squeezing light nuclei together (fusion) both release enormous amounts of energy compared to any chemical reaction.

In this lesson you will learn how uranium-235 undergoes fission, how a chain reaction works, the roles of control rods, the moderator and shielding in a reactor, what nuclear fusion is, why it powers stars, and why achieving fusion on Earth is so difficult.

Objectives

  1. Know that nuclear reactions, including fission, fusion and radioactive decay, can be a source of energy
  2. Understand how a nucleus of U-235 can be split by collision with a neutron, and that this process releases energy
  3. Know that the fission of U-235 produces two radioactive daughter nuclei and a small number of neutrons
  4. Describe how a chain reaction can be set up if the neutrons produced by one fission strike other U-235 nuclei
  5. Describe the role played by the control rods and moderator in the fission process
  6. Understand the role of shielding around a nuclear reactor
  7. Explain the difference between nuclear fusion and nuclear fission
  8. Describe nuclear fusion as the creation of larger nuclei from smaller nuclei, accompanied by a release of energy
  9. Know that fusion is the energy source for stars
  10. Explain why nuclear fusion does not happen at low temperatures and pressures

Lesson Note

A single kilogram of uranium fuel releases roughly two million times the energy of a kilogram of coal. That staggering figure comes from the binding energy holding protons and neutrons together inside the nucleus. Both fission and fusion tap into that store, but in opposite ways.

Available on the Green Bridge App

Download the Green Bridge CBT app on your phone or computer to access full lesson notes, practice questions, and more.

Full lesson notes with diagrams
AI-powered learning assistant
Study offline, anytime, anywhere
Available on Android, Windows, macOS, and Linux

Lesson Evaluation

Congratulations on completing the lesson on Fission And Fusion. Now that youve explored the key concepts and ideas, its time to put your knowledge to the test. This section offers a variety of practice questions designed to reinforce your understanding and help you gauge your grasp of the material.

You will encounter a mix of question types, including multiple-choice questions, short answer questions, and essay questions. Each question is thoughtfully crafted to assess different aspects of your knowledge and critical thinking skills.

Use this evaluation section as an opportunity to reinforce your understanding of the topic and to identify any areas where you may need additional study. Don't be discouraged by any challenges you encounter; instead, view them as opportunities for growth and improvement.

  1. In nuclear fission, a heavy nucleus: A) Absorbs light B) Splits into two smaller nuclei C) Fuses with another nucleus D) Emits only gamma rays Answer: B
  2. The role of control rods in a reactor is to: A) Speed up neutrons B) Absorb neutrons C) Produce neutrons D) Shield workers Answer: B
  3. Nuclear fusion is the energy source of: A) Nuclear power stations B) Coal-fired stations C) Stars D) Batteries Answer: C
  4. Fusion requires very high temperatures because: A) Nuclei are negatively charged B) Nuclei are neutral C) Positive nuclei repel each other D) Neutrons need to be fast Answer: C
  5. The moderator in a reactor: A) Absorbs neutrons completely B) Speeds up neutrons C) Slows down neutrons D) Generates neutrons Answer: C

Available on the Green Bridge App

Download the Green Bridge CBT app on your phone or computer to access full lesson notes, practice questions, and more.

Full lesson notes with diagrams
AI-powered learning assistant
Study offline, anytime, anywhere
Available on Android, Windows, macOS, and Linux

Available on the Green Bridge App

Download the Green Bridge CBT app on your phone or computer to access full lesson notes, practice questions, and more.

Full lesson notes with diagrams
AI-powered learning assistant
Study offline, anytime, anywhere
Available on Android, Windows, macOS, and Linux

Practice Mock Questions

Want to practice mock questions on Fission And Fusion? Download the Green Bridge CBT app to access mock questions and full practice assessments for this topic.

Download The App On Google Playstore

Everything you need to excel in your exams

Green Bridge CBT Mobile App
Personalized AI Learning Chat Assistant
200,000+ Past Papers Across IGCSE, JAMB, WAEC & NECO
Over 3000 Lesson Notes
Offline Support - Learn Anytime, Anywhere
Green Bridge Timetable
Literature Summaries & Potential Questions
Track Your Performance & Progress
In-depth Explanations for Comprehensive Learning