⚡ Show all working — the AI marks against the AQA mark scheme. Method marks awarded for correct working even if the final answer is wrong.
1 markChain reactionAQA 8463 style
What is meant by a chain reaction in a nuclear reactor?
A A series of chemical reactions in the reactor fuel
B Neutrons from one fission event trigger further fission events, releasing more neutrons, sustaining the reaction
C The reactor core heats the coolant which drives a chain of turbines
D The control rods absorb neutrons in a chain sequence
3 marksRole of control rodsAQA 8463 style
Explain the role of control rods in a nuclear reactor and describe what happens when they are fully inserted. (3 marks)
Hint: What they are made of → what they do (absorb neutrons) → effect on chain reaction → what happens when fully inserted.
+30 XP
1 markFusion conditionsAQA 8463 style
Why does nuclear fusion require extremely high temperatures?
A High temperature provides neutrons to trigger the fusion
B High temperature gives nuclei enough kinetic energy to overcome their electrostatic repulsion and get close enough for the strong nuclear force to act
C High temperature separates electrons from nuclei, making fusion easier
D High temperature provides gamma radiation needed for fusion
4 marksCompare fission and fusionAQA 8463 style
Compare nuclear fission and nuclear fusion as methods of generating energy. Consider: fuel, waste, safety, energy output per kg. (4 marks)
Hint: Compare on four points. Be specific — name the fuels and waste products rather than just saying more or less.