Fission And Fusion
Overview
Burning coal releases the energy stored in chemical bonds between atoms. Nuclear reactions reach far deeper, into the nucleus itself, and release something like a million times more energy from the same mass of fuel. Two quite different nuclear processes do this, and confusing them is the classic error in this topic.
This lesson separates them properly. Fission splits one heavy nucleus into two lighter ones and runs every nuclear power station on Earth. Fusion joins light nuclei together and powers every star in the sky. You will meet the chain reaction, the job of the control rods and the shielding, and the reason fusion is so much harder to achieve on Earth than in the Sun.
Objectives
- Know that nuclear reactions, including fission, fusion and radioactive decay can be a source of energy
- Understand how a nucleus of U-235 can be split (the process of fission) by collision with a neutron, and that this process releases energy as kinetic energy of the fission products
- Know that the fission of U-235 produces two radioactive daughter nuclei and a small number of neutrons
- Understand the role of shielding around a nuclear reactor
- Know that fusion is the energy source for stars
Mind map
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Flashcards
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Lesson Note
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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.
- Nuclear fission is best described as: A) Two light nuclei joining together B) A large nucleus splitting into two smaller nuclei C) A nucleus emitting an alpha particle D) An electron being knocked out of an atom Answer: B
- Which process is the energy source of the Sun? A) Fission of uranium B) Burning of hydrogen C) Fusion of hydrogen nuclei D) Radioactive decay of radon Answer: C
- What starts the fission of a uranium-235 nucleus? A) The absorption of a neutron B) The emission of a gamma ray C) Heating the fuel rod D) The absorption of an electron Answer: A
- In a reactor, the purpose of the control rods is to: A) Slow the neutrons down B) Absorb neutrons C) Absorb gamma radiation D) Increase the fuel temperature Answer: B
- Most of the energy released in a fission reaction appears as: A) Kinetic energy of the fission products B) Sound energy C) Light from the fuel rods D) Electrical energy in the core Answer: A
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