Fission and fusion
5.2.4What the syllabus asks of you
- Describe the process of fusion as the formation of a larger nucleus by combining two smaller nuclei with the release of energy, and recognise fusion as the energy source for stars
- Describe the process of fission when a nucleus, such as uranium-235 (U-235), absorbs a neutron and produces daughter nuclei and two or more neutrons with the release of energy
- Explain how the neutrons produced in fission create a chain reaction and that this is controlled in a nuclear reactor, including the action of coolant, moderators and control rods
Read the notes first
Chapter 5: Fission and fusion
Drill this topic
Every question on Fission and fusion, untimed, marked as you go.
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Choose the years and how many questions, then print it with the answers on separate pages.
8 questions
1May / June 2025 · Paper 11 · Q38Show mark scheme →
A92
B141
C144
D327
Mark scheme
2May / June 2024 · Paper 11 · Q39Show mark scheme →
Athe decay of a radioactive nucleus
Bthe joining together of two nuclei to make a larger nucleus
Cthe melting of an unstable nucleus
Dthe splitting of a nucleus into two lighter nuclei
Mark scheme
3May / June 2023 · Paper 12 · Q37Show mark scheme →
Aalpha-particle
Bgamma ray
Cneutron
Dproton
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4May / June 2023 · Paper 12 · Q38Show mark scheme →
Ato absorb all the neutrons in order to stop the chain reaction
Bto produce more neutrons in order to create a chain reaction
Cto remove thermal energy in order to control the chain reaction
Dto slow down neutrons in order to continue the chain reaction
Mark scheme
5Oct / Nov 2021 · Paper 12 · Q37Also set in Oct / Nov 2021 Paper 11Show mark scheme →
AIn the reactor, the main reaction occurs when protons hit uranium nuclei.
BThe process taking place in the reactor is called nuclear fusion.
CThe reactor produces energy to boil water and to produce steam.
DCarbon dioxide is the major waste product from the reactor.
Mark scheme
6May / June 2021 · Paper 11 · Q37Show mark scheme →
ANuclear fusion occurs at low temperatures.
BNuclear fusion occurs only between heavy nuclei.
CNuclear fusion occurs in the formation of many stars.
DNuclear fusion powers most electricity-generating stations.
Mark scheme
7Oct / Nov 2018 · Paper 12 · Q38Show mark scheme →
AIn the reactor, the main reaction occurs when protons hit uranium nuclei.
BThe process taking place in the reactor is called nuclear fusion.
CThe reactor produces energy to boil water and to produce steam.
DCarbon dioxide is the major waste product from the reactor.
Mark scheme
8May / June 2017 · Paper 12 · Q39Also set in May / June 2017 Paper 11Show mark scheme →
Aproduces larger nuclei | is the energy source of a star
Bproduces larger nuclei | releases energy in a power station
Cproduces smaller nuclei | is the energy source of a star
Dproduces smaller nuclei | releases energy in a power station
Mark scheme