Lesson.7: Nuclear Fission, Radioactivity and Energy

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• Lesson.7 Nuclear Fission, Radioactivity and
  Energy
• Objectives
• Describe the process of generating electricity
  using nuclear power.
• Describe the fission process and the meaning
  of the term chain reaction.
• Describe how the chain reaction is controlled
  in a conventional power station.

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Nuclear power stations use uranium as fuel.
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Nuclear power stations use uranium as fuel.

• Electricity is generated as follows
• nuclear reaction
• producing heat
• producing steam
• turning a turbine
• turning a generator.

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What is the nuclear reaction that produces energy
(heat)?
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What is the nuclear reaction that produces energy
(heat)?
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What is the nuclear reaction that produces energy
(heat)?

• uranium nucleus hit by neutron
• causes nucleus to split
• energy released
• this is called nuclear fission

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This is called nuclear fission
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Video
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• Uranium decay can be a chain reaction.
• Chain reaction
• when each uranium nucleus splits more than one
  neutron is given out
• these neutrons can cause further uranium nuclei
  to split.
• A nuclear bomb is a chain reaction that has
  gone out of control.

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• Scientists stop nuclear reactions going out of
  control by
• placing rods in the reactor
• to absorb some of the neutrons
• but allowing enough neutrons to remain to keep
  the process operating.
• Materials can be made radioactive by putting them
  into a nuclear reactor.
• These materials become radioactive when they
  absorb extra neutrons and so become unstable.
• Therefore nuclear fission produces radioactive
  waste.

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S T A T I O N E L M D N
F U S T N U C L E U S O
K C A N U C L E A R S I
U H R O R H A C F H H T
R A D I O A C T I V E C
A I C S T B E R S K A A
N N P S C H A I F U T E
I S T I A P E C I U M R
U R F F E E N I B R U T
M S U T R O P T E L E C
U R E W O P O Y F L E U
D T L G E N E R A T O R
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S T A T I O N E N
N U C L E U S O
C N U C L E A R I
U H O R C H T
R A D I O A C T I V E C
A I S T R A A
N N S C I T E
I I A C R
U F F E E N I B R U T
M U R T
R E W O P Y
L G E N E R A T O R
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Background Radiation

• Is naturally occurring radiation which is all
• around us all of the time.
• It has a variety of sources
• Air, food, building materials, soil, rocks.
• Cosmic rays (mainly from the Sun)
• All living things are a little bit radioactive
• Human activity, radioactive fallout from
  explosions, medical procedures.

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Background Radiation
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Homework Foundation only Complete Background
Radiation and Nuclear Power pages 136 and 137.
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• Learning Objectives
• Recognise that nuclear power stations use
  uranium as a fuel.
• Describe the main stages in the production of
  electricity
• source of energy
• used to produce steam
• used to produce electricity.
• Describe how domestic electricity is generated
  at a nuclear power station
• nuclear reaction
• producing heat
• producing steam
• turning a turbine
• turning a generator.
• Describe what happens to allow Uranium to
  release energy
• uranium nucleus hit by neutron

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• Describe the process that gives out energy in a
  nuclear reactor as nuclear fission.
• Recall that materials can be made radioactive by
  putting them into a nuclear reactor.
• Describe how materials become radioactive when
  they absorb extra neutrons.
• State that nuclear fission produces radioactive
  waste.
• Describe that the decay of uranium can be a
  chain reaction.
• Explain what is meant by a chain reaction
• when each uranium nucleus splits more than one
  neutron is given out
• these neutrons can cause further uranium nuclei
  to split.
• Describe that a nuclear bomb is a chain reaction
  that has gone out of control.
• Explain how scientists stop nuclear reactions
  going out of control