Pearson Edexcel International GCSE (9–1) · PHYSICS · Chapter
Fission and Fusion
47 practice questions
Topics covered
Practice questions
11–20 of 22 · Normal
Question 11
3 marks · Normal
Answer and see the solution →The diagram shows a nuclear fusion reaction used in experiments on Earth.
(a)[1 mark]Name the two isotopes of hydrogen that take part in this fusion reaction.
(b)[1 mark]State one product of this reaction.
(c)[1 mark]Is energy absorbed or released in this reaction? Explain why.
Question 12
3 marks · Normal
Answer and see the solution →Explain why nuclear fusion reactions are the main source of energy in stars, but not in most power stations on Earth.
Question 13
2 marks · Normal
Answer and see the solution →The table shows the mass of particles before and after a nuclear fusion reaction:
Particles Total mass (u) Before: deuterium + tritium 5.031 After: helium + neutron 5.019 Question 14
1 mark · Normal
Answer and check →Which of the following best explains why achieving nuclear fusion on Earth is much harder than in the core of the Sun?
- A.The Sun has stronger gravity, creating higher pressures and temperatures.
- B.Fusion produces less energy in the Sun than on Earth.
- C.The Sun contains more uranium than Earth.
- D.Fusion does not release any energy in the Sun.
Question 15
3 marks · Normal
Answer and see the solution →A scientist suggests using nuclear fusion to power a new type of power station on Earth.
(a)[2 marks]State two advantages of using fusion instead of fission to produce electricity.
(b)[1 mark]Give one technological challenge that must be overcome before fusion reactors can be used commercially.
Question 16
2 marks · Normal
Answer and see the solution →Describe how nuclear fusion in a star results in a stable output of energy over millions of years.
Question 17
5 marks · Normal
Answer and see the solution →For many years, scientists have been working on using nuclear reactions as a source of energy. Nuclear fission and fusion are both involved in producing energy in different ways.
(a)[2 marks]State what is meant by nuclear fission and identify the type of material most commonly used for fission in a power plant.
(b)[2 marks]Explain one major reason why nuclear fusion does not currently power electricity stations on Earth, even though it is the source of energy in stars.
(c)[1 mark]Describe one radioactive product that is produced by nuclear fission.
Question 18
5 marks · Normal
Answer and see the solution →Both fission and fusion reactions release energy. The conditions under which these reactions happen are very different.
(a)[2 marks]State one condition required for fission to occur, and one required for fusion.
(b)[2 marks]Explain why a chain reaction happens more readily with a large mass of uranium-235 than with a small mass.
(c)[1 mark]Suggest one reason why nuclear fusion reactors might be safer than fission reactors.
Question 19
5 marks · Normal
Answer and see the solution →The energy released in both fission and fusion reactions has important consequences for their use as energy sources.
(a)[3 marks]Explain how energy is released in the process of uranium-235 fission, mentioning both the particles produced and how energy is distributed among them.
(b)[2 marks]Describe one advantage and one disadvantage of using nuclear fusion, compared to nuclear fission, for providing electricity.
Question 20
5 marks · Normal
Answer and see the solution →The diagrams below show two types of nuclear reaction used to generate energy on Earth and in stars.
(a)[3 marks]Describe how energy is released in a nuclear fission reactor. Include the roles of the moderator and control rods in your answer.
(b)[2 marks]Explain why nuclear fusion reactions occur readily in stars but are harder to achieve on Earth.