NATIONAL QUALIFICATIONS CURRICULUM SUPPORT
Chemistry
Nuclear Chemistry
Advice and Guidance
for Practitioners
[NATIONAL 5]
This advice and guidance has been produced to support the profession with the delivery of
courses which are either new or which have aspects of significant change within the new
national qualifications (NQ) framework.
The advice and guidance provides suggestions on approaches to learning and teaching.
Practitioners are encouraged to draw on the materials for their own part of their continuing
professional development in introducing new national qualifications in ways that match the
needs of learners.
Practitioners should also refer to the course and unit specifications and support notes which
have been issued by the Scottish Qualifications Authority.
http://www.sqa.org.uk/sqa/34714.html
Acknowledgement
© Crown copyright 2012. You may re-use this information (excluding logos) free of charge in
any format or medium, under the terms of the Open Government Licence. To view this licence,
visit http://www.nationalarchives.gov.uk/doc/open-government-licence/ or e-mail:
psi@nationalarchives.gsi.gov.uk.
Where we have identified any third party copyright information you will need to obtain
permission from the copyright holders concerned.
Any enquiries regarding this document/publication should be sent to us at
enquiries@educationscotland.gov.uk.
This document is also available from our website at www.educationscotland.gov.uk.
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Contents
Planning for learning and teaching
4
Introduction
6
Curriculum for Excellence
7
Starting the learning journey: harnessing the power of the atom – more
harm than good?
9
Our demand for energy: a nuclear solution?
13
A Scottish perspective
14
Issues associated with nuclear power: economics
15
Issues associated with nuclear power: uranium resources
16
Issues associated with nuclear power: radioactive waste
17
Issues associated with nuclear power: sustainability
25
Albert Einstein and the energy from the nucleus
24
The future of nuclear?
27
Global security: a nuclear solution?
30
A Scottish perspective
30
Nuclear weapons and global tensions
31
The creation of nuclear weapons
32
Nuclear weapon design and chain reactions
34
Nuclear fuel and global security: connecting the stories
35
Healthcare: a nuclear solution?
37
Marie Curie: the energy from the nucleus
37
‘This remarkable element’: historical uses
38
‘This remarkable element’: why is it so important?
40
Radiation in medicine
40
Use in diagnoses (radiopharmaceuticals)
41
Use in treatment
43
Radiation and environmental monitoring
44
How much radiation is safe?
45
Background radiation and limiting radiation exposure
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Planning for learning and teaching
This advice and guidance is intended for use by practitioners. It is nonmandatory. It is anticipated that practitioners will be creative and innovative
in planning approaches to meeting the needs of learners. This advice and
guidance should be used in a reflective and selective manner. The model of
the atom used is one that makes reference to sub-atomic particles other than
protons, neutrons and electrons. Practitioners can decide which atomic model
is best suited to their learners.
Reflective questions for learners are provided to aid pra ctitioners in planning
learning and teaching to meet the needs of learners . These questions are
intended for practitioners’ use in the identification of big issues,
consideration of which underpins the learning and teaching for this context.
In many cases, investigative work and inquiry-based practical learning will
supplement the learning and teaching describe d here.
This advice and guidance suggests contexts for learning and ideas for
learning and teaching offering opportunities to prepare learners in the
following mandatory course key areas:
National 5 Chemistry: Nuclear chemistry
 Radiation process; alpha, beta processes; alpha, beta and gamma radiation.
 Specific properties: mass, charge and ability to penetrate different
materials.
 Half-life.
 Use of isotopes to date materials.
 Uses of both nuclear fusion and nuclear fission reactions .
 Nuclear equations.
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By inclusion of appropriate investigative work and skills for learning, life
and work, this nuclear context could also offer opportunities to undertake
learning associated with:
Mandatory course key area ‘Nuclear Energy’ for National 5 Physics
Mandatory course key area ‘Background radiation’ for National 4 Chemistry
Mandatory course key area ‘Human impacts on biodiversity’ for National 5
Environmental Science
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Introduction
Current research suggests that the nuclear sector has a secure future in
Britain, with around 33,000 people being required to deliver the UK’s
proposed nuclear programme.
The nuclear sector offers many exciting and varied career opportunities for
learners in areas including medicine and the energy sector , eg:




nuclear plants to meet power demands
nuclear marine propulsion systems, including for naval warships
applications of nuclear radiation in the diagnosis and treatment of disease
development of the use of nuclear radiation to produce and preserve food
supplies
 development of nuclear power systems for satellites and deep space probes
 regulation and risk management associated with all nuclear applications.
Expertise in this sector will continue to be applicable in the future to address
issues associated with demands for consumer and industri al power, clean
water, food security, environmental issues, health and transportation. Nuclear
radiation also has applications in the oil industry, steel production and
manufacturing. Although there are currently no plans to commission further
nuclear power plants in Scotland, the wide-ranging applications of expertise
in the nuclear sector mean this is an area which may provide long-term
employment opportunities for learners. The European Nuclear Society has
further information on the demand for skilled workers in the nuclear industry.
Preparing learners for learning, life and work is at the heart of Curriculum for
Excellence. Ensuring that they receive the right support and advice
throughout their education is vitally important in helping learners to develop
the relevant skills to progress successfully into employment.
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Curriculum for Excellence
Curriculum for Excellence supports the development of relevant careers skills
in many ways:
 The driving force behind Curriculum for
Excellence is that it is a curriculum for
learning, life and work and it should
fully equip learners with the skills,
knowledge and confidence to thrive and
succeed in the increasingly globalised
world of the 21st century.
 The development of skills within
learners is at the heart of Curriculum for
Excellence in recognition of the fact
that in a fast-changing world, skills will
allow learners to adapt to changing
circumstances and are the key to
success. These include the entire spectrum of skills from leadership to
interpersonal skills to career management skills. Building the Curriculum
4 gives further information about the importance of skills within
Curriculum for Excellence and how they have been embedded within the
experiences and outcomes for all learners, from which the skills wi thin the
learning for National 5 should progress. The Skills for Learning, Skills for
Life and Skills for Work Framework will also aid your planning to meet the
needs of learners.
 Interdisciplinary learning is a key aspect of Curriculum for Excellence and
is an exciting way for schools to develop rich learning experiences that
build upon the strengths and expertise within different disciplines .
Interdisciplinary learning also offers an excellent vehicle for learners to
develop higher-order thinking skills and prepare learners for the life of
work, where interdisciplinary approaches to complex tasks are often the
norm.
 Curriculum for Excellence encourages approaches to learning that are
motivational, fun, relevant, challenging and, importantly, develop the
skills of learners. Such approaches to learnin g include co-operative, active,
collaborative and outdoor learning.
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There are many ways in which this learning journey can develop. Learners’
interests, strengths, prior learning and locality, as well as lo cal, national and
global events should be considered when planning for teaching and learning.
Glow provides an opportunity for learners to work together across
geographical areas.
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Starting the learning journey: harnessing the power
of the atom – more harm than good?
A starting point for this learning context might be to encourage learners to
examine their prior learning around a number of questions:
 The title of this learning context is ‘Harnessing the power of the atom –
more harm than good?’ Consider what might be meant by this title and
what the learning might include.
 What is meant by the words nuclear, radiation and radioactivity?
 Who are the key scientific figures whose work might be relevant to this
learning?
Throughout the learning within this context there are opportunities to
challenge learners’ thinking, eg through a series of key questions presented as
‘myth or reality’, such as ‘all radiation is harmful’, and as learners’
understanding deepens statements such as ‘all radiations are ionising’.
Learners could record a series of 30-second podcasts to explain why each
statement is a ‘myth’ or ‘reality’ and by the end of the learning context would
have available a bank of short revision clips.
Research from the University of York has identified that there can be
misunderstanding of the scientific ideas associated w ith radiation and
radioactivity. This research is referenced by the Institute of Physics on the
IOP website Teaching radioactivity: Summary and suggestions. Evidence
indicates that learners often develop the understanding that objects that are
irradiated themselves become radioactive and can later re -emit the radiation
like a sponge can lose water. This also gives the opportunity to discuss
modelling in science, and the strengths and limitations of modelling in
general and specific models.
This advice and guidance contains teaching ideas and suggestions.
Practitioners may wish to concentrate on only one aspect or several. This
journey outlines the work of two well -known scientific figures: Marie Curie
and Albert Einstein. It is intended to encourage learners to examine the work
of key scientists and consider the uses, applications and impacts of that work.
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Was a particular application or use appropriate at the time? Would it still be
appropriate now? And how do we want our future to look? A very obvious
example of this is the development of nuclear weapons. These questions will
be examined in both Scottish/UK and global contexts.
At the beginning of this learning, learners could explore their understanding
by scripting a conversation between Marie Curie and Albert Einstein,
discussing their scientific work and explaining it to each other. This m ight be
done as role play or by using a simple animation package, such as the
j2spotlight tool available free for Glow users. Alternatively, learners might
storyboard this, either in hard copy or using software , eg Comic Life.
The work of Marie Curie and Albert Einstein revolutionised the world of
nuclear science, and each overcame different but equally significant barriers
to pursue their scientific work. The learning and teaching outlined provides a
rich opportunity for exploration of the historical context in which each of
these scientists was working and the issues faced by Marie Curie as a female
scientist in the early 20th century and by Albert Einstein as a Jewish German
citizen in Europe. Such contexts could be explored by meaningful links with
social subjects.
As the learning progresses, learners could keep a journal of their work and
highlight where it links to the work of Marie Curie and/or Albert Einstein,
reflecting on what each might have thought of new developments and
applications. Where this context is used to overtake learning associated with
both physics and chemistry, such a journal, either online (eg as a Glow blog
or using the j2webby tool available free for Glow users) or in hard copy,
could provide a link for progress.
Another way to record the learning journey may be for learners to create a
timeline of the work of Marie Curie and Albert Einstein , and the development
of understanding of nuclear radiation and its applications through the 20th
and 21st centuries. There are freely available software packages on which a
timeline could be created and developed as the learning progresses, either
individually as an assessment tool or as a group task. Learners may consider
the features of a timeline from familiarity with , for example a Facebook
timeline.
Marie Curie
Marie Curie was born in Warsaw in November 1867. She was the first woman
to receive the Nobel Prize in Physics, in 1903. With the award of the Nobel
Prize in Chemistry in 1911, Marie Curie became the first person to receive
two Nobel Prizes.
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In 1907, Marie Curie set up a teaching co -operative for 6-year-olds which
broke the mould for learning and teaching at the time. Encouraging learners
to construct their own understanding with her guidance, the children were
given the opportunity to undertake practical work associated with learning
previously reserved for 14-year-olds at lycées. Big questions were posed and
the science explored.
I am among those who think that science has great beauty. A scientist in
his laboratory is not only a technician: he is also a child placed before
natural phenomena which impress him like a fairy tale. We should not
allow it to be believed that all scientific progress can be reduced to
mechanisms, machines, gearings, even though such machinery has its own
beauty.
Marie Curie, during a debate in Madrid, ‘The Future of Culture’ (1933).
In Eve Curie Labouisse, Eve Curie and Vincent Sheean, Madame Curie
(1937), 341.
Marie Curie was mocked in the press for encouraging thinking i n learners
whom, it was noted, could barely read and write . However, this did not hinder
the learning, nor recording of the learning. A 13-year-old, Isabelle
Chavannes, was given the responsibility of sitting in and making records of
the lessons. In 2003, these notes were discovered by Madame Chavannes’
nephew and a book published. This was complemented by a website called
Marie Curie’s Lessons, published under Creative Commons Licence for use
by practitioners.
More biographical information for Marie Curie can be found on the Nobel
Prize website and the American Institute of Physics website.
Albert Einstein
Albert Einstein was born in Württemberg, Germany in 1879. During his
lifetime he held Swiss German and US citizenship. In 1921, Albert Einstein
was awarded the Nobel Prize in Physics for services to theoretical physics.
Einstein's best known works of physics include:
 Special Theory of Relativity (1905)
 General Theory of Relativity (1916)
In addition, Einstein published a number of non -scientific works.
The Manhattan Project Heritage Preservation Association, Inc . (MPHPA)
website has a list of 31 pioneers who laid the foundations for nuclear
science in the early part of the 20th century, to aid learning and teaching
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which weaves in the research and contributions from other scientists. Note
that the work of the MPHPA has subsequently been incorporated into that
of the Atomic Heritage Foundation.
More biographical information for Albert Einstein can be found on the Nobel
Prize website.
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Our demand for energy: a nuclear solution?
Nuclear power has been used to produce electricity in the UK since 1956,
when the first large-scale power plant was opened. It currently accounts for
approximately 15–20% of the UK’s energy needs, although in the past it
made a more significant contribution.
The first reactor to produce electricity was in Idaho, USA in 1951. It
produced sufficient electricity to illuminate four light bulbs. Its purpose was
not to produce electricity on a commercial scale but to be an experimental
reactor.
In 1954, the Russians generated the first electricity for commercial use using
nuclear power. Just under two years later, the UK’s first plant, Calder Hall,
produced ten times the power of the Russian plant. In late 2010 there were
441 nuclear plants in 30 countries worldwide.
(European Nuclear Society)
Nuclear power remains a controversial issue. It currently plays a significant
role in meeting the world’s energy demand. The Catalyst article ‘A Nuclear
Future?’ (Gatsby Science Enhancement Programme, 2003) provides a useful
overview for practitioners. Environmentalists are split over the green
credentials of nuclear power; the reactor process itself does not produce
carbon dioxide and it is a very reliable source of energy. However, the small
amounts of waste it produces are radioactive and must be stored and sealed
for thousands of years, during which time they must be protected, eg from
geological threats such as earthquakes and volcanic eruption.
Decommissioning reactors which have reached the end of their lifespan is
also a major challenge; a Catalyst article ‘Decommissioning’ (Gatsby Science
Enhancement Programme, 2003) summarises the process and the challenges .
The International Atomic Energy Agency is an international organisation,
working with the United Nations, which supports member states in planning
for the use of nuclear science and technology. It is also responsible for
developing nuclear safety standards, and the protection of human health and
the environment against ionising radiations.
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Reflective question for learners
 Why is it necessary to have an international agency overseeing atomic
energy development and use?
Ideas for learning and teaching
The website of the European Nuclear Society provides various data associated
with nuclear power plants worldwide, including the number of reactors in use
and the nuclear share of electricity generation worldwide. Such data and its
analysis could provide a focus for development of numeracy skills
appropriate to National 5, including exploring effective data visualisation.
The Defence Dynamics resource Nuclear Power Stations may also provide
data for such interrogation. The Guardian’s Datablog Show and Tell from
March 2012 provides an introduction to the area of data visualisation, its role
in journalism and the media, and examples of various visualisations fr om
around the web.
This may be an opportunity for learners to explore effective, and indeed less
effective, methods of presenting data and information to enhance their ability
to communicate understanding. In addition, the ability to understand the story
of data through a range of presentation tools is a crucial literacy skill. The
webdesigner depot highlights 50 Great Examples of Data Visualization for
interest and inspiration.
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The Scottish perspective
The Scottish Government is committed to achieving a secure, affordable,
low carbon energy future – with a vibrant and growing energy sector that
makes a significant contribution to Scotland’s prosperity.
Scotland has a wealth of clean renewable power opportunities – as well as
significant opportunities for deployment of clean fossil -fuel technologies
and carbon storage. Seizing these opportunities will meet our futur e energy
demands, help tackle climate change, and ensure Scotland ’s energy
security. We do not believe there is an energy gap which only nuclear
power can fill.
The Scottish Government’s response to the UK Government Consultation on
the ‘Future of Nuclear Power’ (October 2007)
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Reflective questions for learners
 Some people are opposed to the use of nuclear power in Scotland. What
are the reasons for this position? What might be the main concerns
regarding nuclear power as part of Scotland’s future?
 How does the Scottish Government’s position compare with that of other
countries? Are there other nations with a clear policy against the use of
nuclear power? Has this position changed and can you identify reasons for
any such changes?
Ideas for teaching and learning
 Learners could consider what they already know about the main energy
resources on which Scotland depends for its energy security. What are the
pros and cons of these energy resources? Start with a think, pair, share and
then try taking it in turns to add information to their shared knowledge.
 Learners could use a website such as GridWatch, which provides
information on the status of National Grid to find out about Scotland’s
main energy sources. Using the data available, learners could confirm or
revisit their ideas on energy sources?
 Compare and contrast the Scottish Government’ s position with that of the
UK Government. Documents on Directgov.uk and in the media may
provide useful background.
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Issues associated with nuclear power: economics
Ideas for teaching and learning
Exploring the economic costs and benefits of nuclea r power is an important
factor in considering the pros and cons of reliance on nuclear power for
future energy security, in Scotland and beyond.
This learning may present issues of reliability of data. Such issues should be
explored with learners as part of developing scientifically literate citizens
able to form informed viewpoints. The World Nuclear Association’s The
Economics of Nuclear Power includes comparative data.
This could form the basis of work relating to the interpretation of graphs and
comparing approaches to data visualisation.
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Articles of interest for this learning:
BBC Science & Environment Cost of nuclear ‘underestimated’
BBC Business Nuclear power’s cost conundrum
Institute of Science in Society The Real Cost of Nuclear Power
University of Melbourne’s nuclearinfo.net Cost of Nuclear Power
World Nuclear Association The Economics of Nuclear Power
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Issues associated with nuclear power: uranium resources
Reflective questions for learners
 Uranium is naturally radioactive. Is it better to harness the energy that
fission creates or leave it where it is in the ground?
 Many countries have uranium reserves and these reserves are expected to
last for approximately 50 years. What obligations do these countries have
to supply uranium for other countries’ electricity suppl ies?
Ideas for teaching and learning
A starting point may be to explore learners’ prior knowledge of uranium. This
section provides opportunities for learners to consider the risks, benefits and
management of the risks associated with use of uranium as a fuel. It may be
helpful for learner to understand the physical and chemical processes
associated with mining uranium in order to develop informed views on
nuclear power based on an in-depth and rich understanding. The World
Nuclear Association website provides detailed information on uranium
mining.
Exploring this issue in depth lends itself to an opportunity for learners to
develop skills in reading journal-style articles. The Energy Watch Group
article ‘Uranium Resources and Nuclear Energy’ (December 2006) could be
used as the basis for a piece of group work to identify key words and
summarise understanding in order to teach others to enhance understanding of
the issues associated with the abundance and cost of uranium resources. This
may be focused on a Scottish or UK perspective, or on the wider global
issues, as appropriate to learners’ interest and prior learning. The Energy
Watch Group also issued a press release ‘Energy Watch Group warns of the
increasing cost of nuclear power’ in 2007.
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Having explored the background and summarised the Energy Watch Group
paper, learners may consider issues of bias in journalism, reporting and
research. Learners might consider the issues raised and search for other
evidence (eg Scientific American’s Ask the Experts ‘How long will the
world’s uranium supplies last?’) to further their understanding, considering
the quality of information, reliability of sources and any potential issues of
bias.
Throughout learning around issues associated with nuclear power, it might be
helpful to keep a ‘barometer’ of learners’ opinions on whether the benefits of
using nuclear power outweigh the risks. It might be helpful to have a number
of challenge cards available which can be used by individuals or groups at
suitable points in the learning to help them to formulate and articulate their
thinking, based on evidence, eg ‘nuclear power is a green option’, ‘nuclear
power does not produce greenhouse gases’ and so on. The j2vote tool
available free to Glow users could be used to ca pture learners’ viewpoints as
the learning progresses.
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Issues associated with nuclear power: radioactive waste
Reflective question for learners
 What is the nature of radioactive waste? What are the issues assoc iation
with radioactive waste and its management?
Ideas for teaching and learning
The World Nuclear Association’s page on waste management provides useful
information and key questions, eg what are the advantages and disadvantages
of the different approaches to dealing with ‘high-level waste’? The Gatsby
Science Enhancement Project Catalyst article (2007) ‘Radioactive Waste
Decisions’ provides background information that could be adapted to use with
learners.
The ongoing issue of radioactive contamination of the beach at Dalgety Bay,
resulting from the dumping of wartime planes with lumi nous dials (see BBC
articles from 2006 and 2012) may provide a topical context for discussion of
this issue. The Scottish Environment Protection Agency (SEPA) controls the
site around Dalgety Bay.
An understanding of the nature of radioactivity and radioactive waste will be
important in the development of informed views on nuclear power based on
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an in-depth understanding. This will include the nature of alpha, beta and
gamma decay, ionisation and ionising radiations, penetration of each of these
radiations in air and shielding. An understanding of the science associated
with radioactivity will allow learners to appreciate the challenges of
managing the in relation to waste products.
There are many simulations and animations available to support learning and
teaching in this area, eg Half-life, Ionisation by alpha radiation, Ionisation by
gamma radiation, Radium decay and Radiation penetration.
A basic model of the atom
When we consider nuclear power, we are dealing with energy released from
the nucleus of the atom. A basic model of the atom, and its nucleus, is
required.
A start point would be to explore prior learning, eg through asking learners to
draw their understanding of the model of the atom. A resource such as the
National Learning Network’s Materials’ Chemistry interactive website or
extracts from the Pearson Longman Inside the Atom series could also be used
the explore this understanding.
This could be used as an opportunity to explore with learners their
understanding of the nature of modelling in science through questions such
as:
 What does an atom look like?
 Has anyone ever seen an atom?
 How has the model of the atom changed over time ? What is the scientific
evidence that has resulted in this changing model?
 To what extent does the model of the atom we are using at this stage
reflect all that is known about the atom?
From this, and a developing understanding of key terms such as atomic
number, mass number and of nuclide notation, isotopes can be introduced.
Nuclear fission
The basis of nuclear power in all of the world’s 430+ reactors is nuclear
fission. It might be helpful to explore with learners the root of the word
fission to enable understanding of the process: learners may be familiar with
the idea of a fissure in teeth, or fissure sealant preventative dental treatment,
or fissures in rocks and ice. An understanding of the word can aid learners’
recall of the process. Similarly familiarity with the words decay,
spontaneous and bombardment could be explored to aid understanding.
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Radioactive decay is the breakdown of a nucleus to release energy and matter
from the nucleus. This is the basis of the word ‘nuclear’. The release of
energy and/or matter allows unstable nuclei to achieve stability. Unstable
nuclei are called radioisotopes or radionuclides.
Reflective questions for learners
 Why are some nuclei and isotopes unstable?
 On the periodic table, identify radioisotopes and consider patterns in terms
of mass number and atomic number.
Spontaneous fission (image courtesy of atomicarchive.com)
Fission occurs when a heavy nucleus disintegrates, forming two nuclei of
smaller mass number. This radioactive decay is spontaneous fission. In this
decay process, the nucleus will split into two nearly equal fragments and
several free neutrons. A large amount of energy is also released. Most
elements do not decay in this manner unless their mass number is greater than
230. There is a wealth of animations and videos available to support learning
and teaching of fission, such as Nuclear Fission Animation.
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Fission can also be induced by neutron bombardment.
Neutron bombardment (image courtesy of atomicarchive.com)
Learners could be asked to explain in their own words their qualitative
understanding of the fission process, differentiating between spontaneous and
induced fission. This would also be an opportunity to introduce the use of
nuclear equations to describe the process, eg:
235
92
U + 01 n 
92
36
1
Kr + 141
56 Ba + 3 0 n + energy
Reflective questions for learners
 Why is a neutron used for the bombardment process rather than, for
example, a proton?
 Explore the work of Fermi and Chadwick, which led to the ability to create
the first transuranium element (ie an element with an atomic number
greater than 92), and the work of Otto Hahn to correct a mistake in Fermi’s
Nobel Prize winning research.
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The alpha particle was discovered and named by Sir Ernest Rutherford in
1899. In alpha decay, a positively charged particle, identical to the nucleus of
helium 4, is emitted spontaneously. This particle consists of two protons and
two neutrons.
Alpha decay
Alpha decay usually occurs in heavy nuclei such as uranium or plutonium,
and therefore is a major part of the radioactive fallout from a nuclear
explosion. Since an alpha particle is relatively more massive than other forms
of radioactive decay, it can be stopped by a sheet of paper and cannot
penetrate human skin. A 4 MeV alpha particle can only travel a few
centimetres through the air.
Although the range of an alpha particle is short, if an alpha decaying element
is ingested, the alpha particle can do considerable damage to the surrounding
tissue. For this reason plutonium, with a long half-life, is extremely
hazardous if ingested. Practitioners may want to consider the poisoning case
of Alexander Litvinenko in 2006.
Atoms emit beta particles through a process known as beta decay. Beta decay
occurs when an atom has either too many protons or t oo many neutrons in its
nucleus. Two types of beta decay can occur. One type (positive beta decay)
releases a positively charged beta particle, called a positron, and a neutrino;
the other type (negative beta decay) releases a negatively charged beta
particle, called an electron, and an antineutrino. The neutrino and the
antineutrino are high-energy elementary particles with little or no mass and
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are released in order to conserve energy during the decay process. Negative
beta decay is far more common than positive beta decay.
Beta decay
This form of radioactive decay was discovered by Sir Ernest Rutherford in
1899, although the neutrino was not observed until the 1960s. Beta particles
have all the characteristics of electrons. At the time of their emission, they
travel at nearly the speed of light. A typical 0.5 MeV particle will travel
about 3 m through the air and can be stopped by 4–6 cm of wood.
Note that the beta particle is an electron released from the nucleus. It is not
an orbiting electron. In the previous section, the basic model of the atom
indicated that the nucleus comprises protons and neutrons. So where does this
electron come from?
Gamma rays are a type of electromagnetic radiation that results from a
redistribution of electric charge within a nucleus. Gamma rays are essentially
very energetic X-rays. Gamma radiation is emitted by excited nuclei and
often accompanies alpha or beta radiation, sin a nucleus emitting those
particles may be left in an excited (higher -energy) state.
Gamma rays are more penetrating than either alpha or beta radiation, but less
ionising. They produce damage similar to that caused by X -rays, such as
burns, cancer and genetic mutations.
The Khan Academy video tutorial Types of Decay could be used to challenge
and extend understanding, starting from an exploration of prior learning of a
basic model of the atom.
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Practitioners could extend these ideas further with the use of nuclear
equations.
Reflective questions for learners
 What is the nature of radioactive ‘waste’ and why is it waste? Are there
other possibilities, eg reprocessing, breeder reactors or fast reactors, that
could make use of the energy available for heating?
 What have the solutions for radioactive waste been in the pa st? Would
these still be acceptable now? An interestingexample may be the Yucca
Mountain high-level radioactive waste repository, the creation of which
was approved in 2002 and cancelled in 2009.
 What are the current solutions for management of radioactive waste ? How
successful are these in terms of the risks of nuclear radiation and managing
these risks?
 Given that all work involving radioactive materials, including medicinal
(diagnosis and treatment), transport and food safety, as well as defence
and fuel, leads to ‘waste’ products, should we limit the global use of
radioactive materials? How would such decisions be made and who
decides who is permitted to benefit from the use of radioactive materials?
 Given that all work involving radioactive materials leads to ‘waste’
products, what factors must be taken into account to minimise the risks
associated with the management of the waste? Some factors to consider
might be population density, environmental issues, geological make-up (eg
clay, shale and unfractured granite provide potential repositories due to
porosity and permeability) and the stability of the site. This may provide
opportunities for linking with learning in geography and environmental
science.
In considering radioactive materials and waste, learning and teaching may
explore the timescales for which waste remains at hazardous levels of
radioactivity. An understanding of the nature of radioactive decay and half life will play an important role in learners’ fully understanding the issues
around the risks and benefits of a nuclear future.
An introduction to the random nature of radioactive decay can be given by
using a simulation, such as Radioactive decay. A simple practical activity can
illustrate this further and introduce the idea of half -life.
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Exemplification of learning and teaching: half-life – when does an atom
or nucleus ‘decide’ to decay?
This activity provides an introduction to the concept of half-life. Each group
of learners is provided with: 100 × 2p coins, 100 × 1p coins and a plastic
beaker. The coins represent nuclei and the use of this very basic model to
represent radioactive decay provides opportunities for learners’ evaluation of
the effectiveness of modelling in science to aid understanding.
1.
Learners count and record the number of 2p coins and place them in the
beaker.
2.
The beaker is shaken to mix the coins Learners are asked to predict
when they pour the shaken 2p coins onto the table which will be heads
and which will be tails. Learners should be able to confidently predict a
mixture of heads and tails but recognise it is not possible to identify in
advance the outcome for any particular coin.
3.
Following discussion, learners pour the shaken 2p coins on to the table
and count the number of coins which have landed heads up . These coins
remain and the number of head-up coins after one shake is recorded.
The coins which landed tails up are removed and replaced by 1p coins.
This illustrates that a percentage of the nuclei have decayed but not
disappeared – they decay into another nuclei represented by the 1p coin.
4.
The mixture of head-up 2p coins and replacement 1p coins (total still as
at the beginning of the task) is returned to the beaker. The beaker is
shaken vigorously and the coins poured on to the table. Learners count
the number of coins which have landed heads up . These coins remain
and the number of head-up coins after two shakes is recorded. The 2p
coins which landed tails up are removed and replaced by 1p coins.
5.
This is repeated until there are no 2p coins remaining. Learners may
comment on the number of shakes it takes until the final few 2p coins
land tails up, compared with the number landing tails up in the first few
shakes. This observation of the rate of decay can then be linked to the
graphing work which follows.
6.
The data gathered can be graphed and gives the characteristic
exponential decay graph, which enables the half-life, defined as ‘the
time taken for half the nuclei in a sample of specific isotopes to
undergo radioactive decay’, to be calculated.
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This provides an opportunity for learners to use prior learning associated with
graphing skills or to enhance skills in using ICT for graphing. There is a rich
opportunity to enhance learners’ skills in interpreting graph shapes ..
Reflective question for learners
 How will the half-life of the coin sample be affected by changing the
number of coins in the sample? Predict, observe and explain your findings.
The Khan Academy video tutorial Half-life could be used to challenge and
extend understanding, starting from an exploration of the number of atoms in
a mass of carbon-12. This tutorial discusses probabilities in more detail.
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Issues associated with nuclear power: sustainability
Sustainable development education and the development of learners as global
citizens are key themes across learning within Curriculum for Excellence ,
ensuring that learners explore in-depth themes relating to energy use, the
environment, climate change, sustainable lifestyles and the impact of
humankind on the planet and its eco-systems.
The World Wildlife Fund (WWF) report ‘Learning for Sustainability in
Schools: Effective Pedagogy’ (2010) in its conclusions (page 20) identifies
the pedagogical approaches common to schools practising effective learning
for sustainability.
Professor David Mackay, Professor of Natural Philosophy at the University of
Cambridge, presents a short video ‘Innovation for Sustainability’, which
outlines three essential actions to reduce individuals’ impact on the planet.
Ideas for learning and teaching
 Consider the CO 2 emissions from the life cycle of a nuclear power station
against a coal-fired power station or wind turbine development. What are
the issues which must be considered for fair comparisons?
 Learners could view a range of video clips supporting and/or challenging
the idea that nuclear fuel could be a sustainable way of meeting global
energy demands. Learners could participate in a structured debate or create
a news article or leaflet that deliberately identifies and references selected
evidence to give a biased viewpoint for or against the use of nuclear fuel.
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 The 2010 TED talk ‘Does the World Need Nuclear Energy’ may help
learners to examine how to construct and present an argument, and to
summarise key points succinctly. Learners could ‘critique’ the debate to
form success criteria against which to self and peer assess a de bate on
nuclear energy.
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Albert Einstein and the energy from the nucleus
What is the significance of the work of Albert Einstein in considering
nuclear power?
In 1905, a series of four papers by Albert Einstein wa s published in the
journal Annalen der Physik. One of these, ‘Does the inertia of a body depend
upon its energy content’, led us to one of the best-known relationships in the
world:
E = mc 2
But what does this mean? And what is its significance?
E = mc 2
E is energy measured in joules (J)
m is mass measured in kilograms (kg)
c is the speed of light in a vacuum (m s –1 )
 The best person to explain the significance is Albert Einstein himself. A
recording of his explanation can be listened to on the American Institute of
Physics website, and a transcript of this recording is also available. In
addition, PBS Nova Teachers website Einstein’s Big Idea has 10 top
physicists, including two Nobel Prize winners, describing in 3 minutes o r
less what E = mc 2 means. This website also contains learner and teacher
guidance for investigative work to explore the relationshi p between energy
and velocity. In The Equation Today three young physicists explain how E
= mc 2 plays out in their work
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Reflective questions for learners
 What were the roots of scientific discovery relevant to the equation
E = mc 2 ?
 What does E = mc 2 mean in terms of nuclear power? Einstein suspected
that his equation could be tested using radium, discovered by Marie Curie
in 1898.
Nuclear fission and E = mc 2
235
92
U + 01 n 
92
36
1
Kr + 141
56 Ba + 3 0 n + energy
Mass number and atomic number are both conserved during fission reactions.
Even though the mass number is conserved, when the masses before and after
the fission are compared accurately, there is a mass difference. The total
mass before fission is greater than the total mass of the products. This brings
us back to Einstein’s equation:
Reflective question for learners
 How does the energy available from a fission reaction compare with the
energy available from, for example, burning coal?
This from given data, particularly as this will provide an opportunity to
consider significant figures, eg calculate the energy released during this
fission reaction.
235
92
97
1
U + 01n  137
56 Ba + 42 Mo + 2 0 n + energy
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The future of nuclear
For some time, governments have sought to become less reliant on nuclear
fission. However, as we face a future in which oil and other fossil fuel
resources become increasingly scarce, it may become necessary for society to
either re-examine approaches to reducing our demand on these resources or
seek alternatives. Fuelling the world’s ever -increasing population in the
future may require another nuclear solution.
In looking to the future, learners may also explore existing fission reactor
design to understand that nuclear technologies are not static, for example
there is development of safer and more efficient nuclear fuels for use in
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fourth generation reactors. Learning and teaching could be progressed to
allow learners to participate in structured debate around risks and benefits,
and our ability to manage the risks associated with nuclear power. The
Institute of Ideas Debating Matters ‘Topic Guide: After Fukushima, We
Should Abandon Nuclear Power’ is aimed at 16–19-year-olds. The structure
would work within the senior phase, with adaptation of materials to meet the
needs of learners as appropriate.
A future with fusion
‘Fusion is energy’s future’, by physicist Steven Cowley, chief executive
officer of the United Kingdom Atomic Energy Authority and head of the
EURATOM/CCFE Fusion Association, provides an introduction to nuclear
fusion. His article in The Guardian, ‘Nuclear Fusion – What is it Worth?’,
provides a useful summary discussion of the role of nuclear fusion in meeting
our future energy needs.
There is a wealth of resources and materials available to form t he basis of
learning and teaching on fusion, eg the Atomic Archive’s animation of
fusion, the Institute of Physics lecture series ‘Powering the Future’, Planet
Science Cold Fusion and the BBC’s ‘How to build a star on Earth’.
Nuclear fusion
Nuclear energy can be released by the fusion of two light elements (elements
with low atomic numbers). In a hydrogen bomb, two isotopes of hydrogen,
deuterium and tritium, are fused to form a nucleus of helium and a neutron.
The immense energy produced by our Sun is as a result of nuclear fusion.
Very high temperatures in the Sun (2.3 × 10 7 K according to NASA) supply
sufficient energy for nuclei to overcome repulsive forces and fuse together.
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When nuclei fuse, the final mass is less than the initial mass, ie there is a
mass difference or mass defect. All elements on Earth come from stellar
fusion.
Deuterium is an isotope of hydrogen that has two protons in its nucleus
(heavy hydrogen). Tritium is another hydrogen isotope (super heavy
hydrogen) and has three protons in its nucleus. Deuterium is naturally
occurring in seawater and tritium can be made from lithium, which is readily
available on Earth. A 2007 Technology Review article ‘Mining the Moon’
provides more detail on fusion reactors.
Fusion has been successfully achieved with the hydrogen bomb. However,
this was an uncontrolled fusion reaction and the key to using fusion as an
energy source is control.
The Joint European Torus (JET), in Oxfordshire, i s Europe’s largest fusion
device. In this device, deuterium–tritium fusion reactions occur at over 100
million Kelvin. Even higher temperatures are required for deuterium –
deuterium and deuterium–helium 3 reactions (see http://www.jet.efda.org/).
ITER in France is the next step towards testing the feasibility of fusion as a
commercial energy source.
Reflective question for learners
 By comparing and contrasting the issues associated with nuclear fission
and nuclear fusion, should nuclear power play a role in our global future?
When structuring your comment, consider the evidence that you are
referencing, including issues such as potential bias and reliability.
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Global security: a nuclear solution?
A Scottish perspective
Nuclear arms as weapons or deterrents have been the subject of much debate
over the last 60 years.
Consideration of nuclear weapons and nuclear-powered military vessels in a
Scottish, UK or global perspective provides opportunities for learners to
consider the ethical, moral and economic issues that often accompany
scientific and technological advances. The National STEM Centre e -library
includes resources from Defence Dynamics incorporating a short video and
useful resource containing various articles relating to the Royal Navy’s
nuclear powered submarine fleet. In addition, the BBC’s Trident missile
factfile provides useful information.
Several groups have taken action against Britain’s nuclear deterrent, Trident,
including the Campaign for Nuclear Disarmament and Trident Ploughshares,
a group set up specifically to oppose the Trident programme. In 2006 a year long protest at Trident’s base at Faslane, named Faslane 365, was initiated
with the aim of blockading the base every day for one year.
The 2004 Kursk Disaster could be used as an illustrative example of the risks
associated with a nuclear-powered and -equipped submarine fleet. The BBC’s
material on the Kursk disaster also considers political issues associated with
military defence systems and this provides a rich context for learners to again
consider risks and how these risks are managed.
Consideration of the use of nuclear fuel for powering military vessels, the
development of nuclear missiles and the role of nuclear weapons as a
deterrent may lend itself to using a STEM Ambassador with expertise in the
defence industry to participate with practitioners to support learning and
teaching.
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Nuclear weapons and global tensions
The issue of countries’ nuclear weapons programmes, either current or
intended, has throughout the past 60 years raised international tensions.
The Cold War was a period of intense political and military tensio n between
the Western powers (the USA, NATO and allies) and the former Soviet Union
and its allies, lasting from the end of World War II until approximately 1991,
when the Soviet Union collapsed. The tensions were heightened by a very
real fear of the use of nuclear weapons by either side, particularly during
periods of intense crisis such as the Korean War (1950 –1953), the Cuban
Missile Crisis (1962) and the Able Archer 83 NATO exercises (November
1983).
The Institute for Science and International Securi ty provides information on
Nuclear Weapons Programs Worldwide: An Historical Overview.
Development of weapons programmes continues to be a cause of global
tension, requiring careful diplomacy and negotiation.
Reflective questions for learners
 The UK and the USA have nuclear weapons programmes. Are we entitled
to have a say in whether or not other countries develop nuclear weapons?
 Why are we concerned about nuclear programmes in other cou ntries, and is
this concern based on evidence and fact?
An illustrative example for consideration may be that of Iran. In November
2011, the International Atomic Energy Authority indicated its con cern over
Iran’s uranium enrichment programme, which may provide capacity for Iran
to develop nuclear weapons.
Learners could explore the ethical and moral issues, and the role of the
International Atomic Energy Authority, in monitoring nuclear weapon
development globally. The Institute for Science and International Security, in
addition to detailed documents relating to the nuclear programme in Iran, also
profiles nuclear programmes in other countries. In this video clip from The
Guardian, Barack Obama (speaking in March 2012 ahead of an international
summit on nuclear security) urges North Korea and Iran to abandon their
nuclear weapons programmes. PBS has a series of activities to support
debating the control of nuclear weapons, which could be adapted for use in
learning and teaching.
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The creation of nuclear weapons
Information on the Manhattan Project, the project to develop usable nuclear
weapons during World War II, can be found at the Atomic Heritage
Foundation website. Six thousand scientists, under the leadership of Robert
Oppenheimer, worked in complete secrecy on the project.
Below are Robert Oppenheimer’s words on the day of the first successful test,
named Trinity, on Monday 16 July 1945 at 05:30.
We knew the world would not be the same. A few people laughed, a few
people cried, most people were silent. I remembered the line from the
Hindu scripture, the Bhagavad-Gita. Vishnu is trying to persuade the
Prince that he should do his duty and to impress him ta kes on his multiarmed form and says, ‘Now, I am become Death, the destroyer of worlds.’
I suppose we all thought that one way or another.
Robert Oppenheimer
The atomicarchive.com allows you to hear and watch Oppenheimer. An
article from Life Magazine in August 1945 ‘Terribly more Terrible’ based on
an interview with Oppenheimer, and published after his resignation and
warning to Congress regarding future atomic weapon development , may also
be of interest.
Reflective questions for learners
 What were the circumstances which led to the acceleration of the research
into building an atomic weapon? By considering the available evidence,
comment on whether or not this decision was appropriate at the time.
 Again by considering available evidence, comment on the development of
atomic weapons through the Manhattan Project and whether this decision
was appropriate, with the benefit of hindsigh t of the global impact in the
65+ years since the Trinity test took place. It may be useful to consider
viewpoints of the time from newspaper archives.
 What are the effects of nuclear weapon deployment such as at Hiroshima
and Nagasaki? Consider the evidence of both immediate and long-term
impact. Sources such as the atomicarchive.com article ‘The Effects of
Nuclear Weapons’ provide rich information for consideration.
 Should nuclear weapons be part of our Scottish, UK or global future?
Justify your response with supporting evidence.
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The NuclearFiles.org project of the Nuclear Age Peace Foundation indexes
recent publications associating with political, military, religious and
scientific perspectives on nuclear weapons to aid practitioners in planning for
learning and teaching in this context. A role play placing those involved with
the development of the atomic bomb on ‘trial’ may be an approach allowing
learners to bring together their learning, summarising it for others and
reflecting on their views.
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In the early 1920s physicists identified fusion of hydrogen into he lium as the
energy source of the Sun. In 1938 nuclear fission was discovered, and shortly
after this came the realisation of the potential of atomic weapons. Whilst the
Manhattan project pursued the development of a ‘basic’ atomic weapon, some
scientists, notably US scientist Teller, continued to seek to build a ‘super’
bomb, in spite of opposition by Robert Oppenheimer.
atomicarchive.com includes information on the events which led to approval
for the pursuit of a thermonuclear -boosted atomic bomb, leading to the Soviet
testing of ‘Joe-1’ in 1949 and the US testing of ‘George’ in 1951 and ‘Mike’
in 1952. Such were the tensions associated with the race between the USA
and the Soviet Union to develop the superbomb that in 1954 the US began a
series of security hearings. Robert Oppenheimer’s post -war lobbying for an
international body to allow peaceful sharing of atomic energy information
and minimise weapon development led to accusations of him being a
‘hardened communist’ and a ‘spy’ (letter to the FBI Director, J Edgar Hoover
written in November 1953). Teller testified against Oppenheimer. It was not
until 1995 that Oppenheimer, and other leading physicists of the era Bohr,
Fermi and Szilard, were formally cleared by the FBI of complicity in Russian
espionage.
Einstein was not involved in the development of the world’s first atomic
weapons. However, so concerned was he about the potential for Germany to
develop such weapons in advance of the Allies that on 2 August 1939 he
wrote to the President of the United States of America, Franklin D Roosevelt,
warning him of the possibility. Einstein later indicated that urging the USA to
develop nuclear weapons was the ‘greatest mistake of his life’. Whether or
not Germany was developing, or had developed, the capability for atomic
weapons remains controversial and the evidence is unclear.
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Nuclear weapon design and chain reactions
Reflective question for learners
 What were the barriers in terms of understanding physics in the design of
the atomic weapons which brought World War II to an end?
atomicarchive.com has short movie clips to illustrate the design of the Fat
Man and Little Boy bombs.
Terms such as critical mass, spontaneous fission, neutrons, binding energies,
enrichment and chain reactions may be explored in this learning.
Chain reactions
A chain reaction refers to a process in which neutrons released in fission
produce an additional fission in at least one further nucleus. This nucleus in
turn produces neutrons, and the process repeats. The process may be
controlled (nuclear power) or uncontrolled (nuclear weapons).
U 235 + n → fission + 2 or 3 n + 200 MeV
If each neutron releases two more neutrons, then the number of fissions
doubles each generation. In that case, in 10 generations there are 1024
fissions and in 80 generations about 6 × 10 23 (a mole) of fissions.
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Nuclear fuel and global security: connecting the
stories
The learning and teaching around nuclear fuel and nuclear weapons leads to
an understanding that the same science underpins both , ie our ability to
harness the power of the atom.
Question for exploration with learners
 What differentiates the nuclear bomb from the nuclear reaction within a
fission or fusion reactor?
The technologies to manage the risks of nuclear fissions and keep the reaction
under control essentially differentiate between nuclear reactors and nuclear
bombs. Control and containment of the reaction are vital. An approach to
learning and teaching would be to examine the Chernobyl disaster in 1986
and compare and contrast it with the situation arising at Fukushima following
the earthquake and tsunami that struck Japan in 2011. There is a vast range of
resources, media articles and news and video footage available to support this
learning and teaching, eg PBS NewsHour Extra’s practitioner and learner
resources Japan’s Nuclear Plants Cause Science and Health Concerns ,
Nuclear Power Plant failures in Japan Raise Safety Questions and After Japan
Nuclear Crisis, New Interest in Chernobyl, and the BBC News articles Japan
Earthquake Explosion at Fukushima Nuclear Plant and The Chernobyl
Disaster.
Reflective questions for learners
 How did the designs of the Chernobyl and Fukushima nuclear plants differ ,
if at all?
 Are there any differences between the design of the nuclear plants at
Chernobyl and Fukushima, and typical reactor design in the UK?
 What are the technologies used to control to chain reaction in nuclear
fission reactors?
 What are the technologies of reactor and plant design which minimise risks
to the environment, workers and local residents?
 To what extent can we plan and prepare for the ongoing impact of
environmental disasters such as tsunamis and earthquakes?
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 Compare and contrast international reaction to these two separate crises,
25 years apart.
Learners could produce a video-based documentary comparing and
contrasting the nuclear crises at Chernobyl and Fukushima , based on the
science underpinning the processes, control and containment issues and the
biological and environmental impacts of radiation. Alternatively, The
Debating Matters Topic Guide ‘After Fukushima We Should Abandon
Nuclear Power’ could be adapted for use with learners.
Examining the historical development of nuclear weapons and the political
issues associated with this development offers rich opportunities to exam ine
the cultural impact of the Cold War and nuclear age, and the social
commentary of the time. For example, the article ‘You and the Atomic Bomb’
written in 1945 by George Orwell provides an exceptional insight into his
thinking at the time. Learners may also consider Cold War propaganda and
how the nuclear threat featured.
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Healthcare: a nuclear solution?
Marie Curie: the energy from the nucleus
In 1896 Henri Becquerel discovered that uranium salts emitted rays that were
similar to X-rays in their ability to travel through black paper and expose
photographic film. This discovery was made while researching
phosphorescence, following earlier studies. Becquerel demonstrated that this
radiation did not depend on an external source of energy, but seemed to arise
spontaneously from uranium itself.
Following Becquerel’s discovery, Marie Curie continued to research and
experiment on uranium and the emitted rays. Using an electrometer, Curie
showed that the radiation was not the outcome of some interaction of
molecules, but must come from the atom itself. Further research of
radioactivity brought about the discovery of additional radioactive elements.
In July 1898, Curie and her husband Pierre published a paper together,
announcing the existence of an element which they named ‘polonium’, in
honor of her native Poland. In December of the same year, the Curies
announced the existence of a second element, which they named ‘radium’ for
its intense radioactivity, a word that they coined. The American Institute of
Physics has further information on the discovery of polonium and radium.
In 1903, Becquerel shared the Nobel Prize in Physics with Pierre and Marie
Curie ‘in recognition of the extraordinary services he has rendered by his
discovery of spontaneous radioactivity’. Becquerel’s 1903 Nobel Lecture ‘On
radioactivity, a new property of matter’ is available on the Nobel Prize
website.
Reflective questions for learners
 In what way(s) did the work of Becquerel and the Curies change scientific
thinking at the time?
 What new scientific questions arose from their work?
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Eight years later, in 1911, Marie Curie received the Nobel Prize in Chemistry
‘in recognition of her services to the advancement of chemistry by the
discovery of the elements radium and polonium, by the isolation of radium
and the study of the nature and compounds of this remarkable element.’
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‘This remarkable element’: historical uses
Within years of its discovery radium, an alpha emitter, was widely used to
treat skin cancers and disfigurements such as port wine stains. Patients would
hold a tube containing radium salts against their skin for a specified length of
time. Patients reported full recovery from conditions previously considered
incurable.
Radium was observed to remain hot indefinitely As a result of this
observation, and the ‘evidence’ of its curative effects on skin, it was widely
considered a miracle elixir. Many companies added radium to daily products
such as shampoo, bath salts and even cigarettes .
This extract from Every Woman’s Encyclopaedia in 1910 confirms the idea of
the miraculous properties of radium:
The woman's medical notebook would not be complete without some
reference to the almost miraculous properties of radium in the treatment of
skin diseases. For one thing, this remarkable remedy was discovered by a
woman, Madame Curie, whose name is famous throughout the entire
scientific world. The effect of radium in the treatment of skin disease is
due to the quality of ‘radio-activity’ it possesses. This means that radium
is constantly giving off rays which can penetrate solid substances, and
have the power of affecting a photographic plate. The medical importance
of Madame Curie’s discovery of radium can be understood when it is
stated that radium rays act on body tissues, destroying unhealthy cells in
the most remarkable fashion. After one or two applications of radium a
large, dark, hairy mole, a port-wine stain on the face, an eczema of years
standing will disappear altogether.
Additionally, in 1903, J.J. Thompson wrote a letter to the journal Nature in
which he described the presence of radioactivity in well water. This led to the
discovery by others that the waters in many of the world ’s most famous
health springs were radioactive. In 1910 the US Surgeon General Dr George
H. Torney wrote, ‘Relief may be reasonably expected at the Hot Springs from
various forms of gout and rheumatism, neuralgia, metallic or malarial
poisoning, gastric dyspepsia, chronic diarrhoea, chronic skin lesions, etc.’
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Such claims led many to believe that it would be beneficial to add radium to
water, including drinking water, and numerous companies developed products
that would add radium to household water. The Oak Ridge Associated
Universities article ‘Radioactive Curative Devices and Spas’ includes more
information, with Radioactive Quack Cures showing many of the products
available as late as the 1960s, and one still for sale in 2005.
Reflective questions for learners
 Henri Becquerel and Marie Curie both reported burns while working with
radium. It was used to remove skin cancers and was widely sold across
Europe and America. What steps could have been taken before this
potentially dangerous chemical was mass produced for consumption? What
do you think the likelihood is of a potentially dangerous compound being
mis-sold now?
 Marie and Pierre Curie did not patent their method ology for extraction.
However, radium was difficult to extract. Many of the pr oducts sold
claimed to contain radium. How could these claims be tested?
 Who is responsible for protecting the public from potentially harmful
compounds? Do different rules apply for medical and non -medical
products?
These questions may provide opportunities to discuss the ethical implications
of drug development, including testing and marketing. It may be helpful for
learners to examine parallels with a case unrelated to radiation, for example
thalidomide or hormone replacement therapy.
It may be that practitioners could use the claims that were made about radium
to develop work in scientific literacy. Learners could consider the validity of
claims. The information from the Dihydrogen Monoxide Research Division
website could be used by learners, in developing an argument for or against
the use of a new chemical. The website explores the evidence against the
dangerous compound dihydrogen monoxide (water).
Throughout World War I, Marie Curie, with the help of her daughter Irene,
devoted herself to the development of the use of X -radiography. In 1918 the
Radium Institute, the staff of which Irene had joined, began to operate in
earnest and it was to become a universal centre for nuclear physics and
chemistry. From 1922, Marie Curie devoted her researches to the study of the
chemistry of radioactive substances and the medical applications of t hese
substances.
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‘This remarkable element’: why is it so important?
It is estimated that more than 1 in 3 people in Scotland will develop some
form of cancer during their lifetime, and that around 1 in 9 males an d 1 in 7
females will develop some form of cancer before the age of 65 . Just over
29,500 new cases of cancer were diagnosed in Scotland in 2009. For males,
the most common cancers are prostate, lung and colorectal cancers,
cumulatively accounting for 53% of cancers in men. For females, the most
common cancers are breast, lung and colorectal cancers, accounting for 56%
of cancers in women. The summary report ‘Cancer in Scotland’ (2011)
published by the Information Services Division of the NHS National Service
Scotland provides more information.
This report concludes that over the last decade there has been substantial and
significant improvement in the probability of surviving cancer in the long
term. These improvements come partly from improved diagnoses and
treatment with nuclear medicine. In Scotland, in 2004/05 there were over
70,000 nuclear procedures carried out.
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Radiation in medicine
We must not forget that when radium was discovered no one knew that it
would prove useful in hospitals. The work was one of pure science. And
this is a proof that scientific work must not be considered from the point of
view of the direct usefulness of it. It must be done for itself, for the beauty
of science, and then there is always the chance that a scientific discovery
may become like the radium a benefit for humanity.
Marie Curie, Lecture at Vassar College, Poughkeepsie, New York (14 May
1921). In Cambridge Editorial Partnership, Speeches that Changed the World,
53.
This section explores the use of radiation in medical diagnosis and treatment.
The Information Services Division of NHS National Services Sco tland is a
useful resource containing facts and figures relating to health. Information
from this resource could be used to contextualise and enrich this learning.
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Use in diagnosis (radiopharmaceuticals)
Technologies making use of radiation and radioactive materials can be used
to diagnose a range of conditions including cancers, heart disease. They can
also be used to monitor physiological processes including liver and kidney
function, blood flow to the brain and bone growth. There are over 200
radioisotopes used on a regular basis in medicine . It is important for learners
to be clear on the distinction between diagnostic techniques and treatment
approaches that involve radioactive materials, as these are often confused.
This is an opportunity to explore the differing penetration of alpha, beta and
gamma radiation. If radioactive sources are available these could be use d to
illustrate radiation safety along with demonstrating the penetration of each of
the radiations in air and the shielding, which can be used to block radiations.
There are many images available illustrating the penetration distances of
each. Animations are also available.
This could be used as a discussion with cards to help learners come to a
conclusion about the inherent dangers of each type of radiation. Learners
could be asked to rank alpha, beta and gamma radiation in order of danger.
Learners could revisit and re-evaluate their thinking as their learning
progresses.
Some questions to prompt discussion might be:




Why does gamma radiation penetrate more?
Which type of radiation is more dangerous?
How can the risks of exposure be minimised?
How could the differences between alpha, beta and gamma radiation be
exploited for medical or other uses?
SSERC is an excellent link for more practical ideas and health and safety
advice.
Diagnostic techniques in nuclear medicine use gamma-emitting radioactive
tracers injected into the body or administered by inhalation or orally.
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Reflective question for learners
 Why is a gamma emitter used as a tracer?
The tracers are generally short-lived isotopes bonded to chemical compounds
that are matched up to particular physiological processes. Through research
and patient trials, chemicals that are absorbed by specific organs have been
identified. The thyroid, for example, absorbs iodine and the brain absorbs
quantities of glucose (fludeoxyglucose 18F-FDG, which is a fluorine-18
glucose radiopharmaceutical). Gamma cameras can be placed over the patient
to detect the path of the tracer. Alternatively, i mages are constructed using
multiple gamma cameras to view organs from many different angles, with the
image constructed and enhanced by computer technologies. It may be
appropriate for learners to explore gamma camera technologies .
Positron emission tomography (PET) (a positron being the anti-particle of the
electron) is a more precise and sophisticated technique using isotopes
produced in a cyclotron (one of the earliest types of particle accelerator) . PET
relies on the positron-emitting radionuclide being introduced and
accumulating in the target tissue. As it decays, a po sitron is emitted which in
combination with an electron emits two simultaneous gamma rays at 180 °.
Detection of these gamma rays allows very precise indication of the location
of the target tissue. A simulation of PET scanning is available from the IOP’s
Inside Story.
New procedures combining PET with Computerised Tomography scans
enable a significant improvement in diagnosis when compared with a
traditional gamma camera used alone.
Gamma imaging by any of these methods allows a view of the position and
concentration of the radioisotope within the body, which provides important
information for diagnostic purposes. Problems with organ function can be
identified either by an indication of insufficient take -up of the radioisotope
(indicating a blockage or lack of function) or an excess take -up of the tracer.
Reflective questions for learners
 How do nuclear imaging techniques compare with traditional or advanced
X-ray techniques?
 Explore the choice of radioisotopes for nuclear medicine and consider why
these are appropriate choices in terms of half -life, their chemistry, the
emission from decay and logistical issues.
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Use in treatment
Rapidly dividing cells are particularly sensitive to damage by radiation. As a
result, it can be possible to control or destroy cancerous growth using
targeted radiation. A radioactive cobalt-60 source is commonly used to
produce a targeted gamma beam, although some radiotherapy treatments are
now carried out using a high-energy X-ray source.
A simulation of radiotherapy use to treat a tumour is available from the IOP’s
Inside Story.
Internal radiotherapy can also be used. A small radiation source, usually a
gamma or beta emitter, is implanted in the target area.
Therapeutic procedures can also be palliative , ie relieve pain. Learners may
explore which radiopharmaceuticals are used and why their particular
properties make them an appropriate choice.
New technologies in the use of radiation for treatments, and particularly
cancer treatments, are continually developing. Some examples which learners
could research are:
 targeted alpha therapy (TAT) – high-energy alpha emissions for the
control of dispersed cancers
 neutron capture therapy using boron -10, which concentrates in malignant
brain tumours
 proton or hadron cancer therapy
 combined proton and PET therapy.
Reflective questions for learners
 Consider the planning for radiotherapy and how the treatment is delivered.
Why is it done in this way?
 Nuclear radiation can destroy human cells. Why is it used to treat humans?
 What are the risks associated with using radioactive material in medical
treatment, both for the patient and for healthcare workers ?
 What would influence the type of radioactive source t hat is chosen?
Consider why gamma emitters are used for diagnosis? Why are beta
emitters often used for treatments?
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Idea for learning and teaching
 Research some internal radiotherapy treatments for cancers and non malignant conditions. What radiochemicals and techniques are used, and
what are the risks and benefits of internal radiotherapy?
Learners could use their learning from this section to prepare a patient leaflet
to explain the use of a radioisotope of choice . Learners could choose their
audience based on the likely prevalence of the illness in the population.
Learners may also incorporate information on the likely side effects, the
biological effects of the treatment, the type of radiation used and why it is
suitable for this treatment, as well as safety precautions that must be observed
during or after the period of treatment.
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Radiation and environmental monitoring
Ice-core records are an important and effective method of monitoring long term temperature levels and environmental gas levels, and form much of the
basis of our understanding of climate change over time.
A number of resources to support practitioners’ understanding, and learning
and teaching associated with ice cores and radiation are availa ble:
Education Scotland Exploring Climate Change Ice Cores
9400 years of cosmic radiation and solar activity from ice cores and tree rings
Climate Data Information
BBC News Ice cores unlock climate secrets
British Antarctic Survey Ice Cores and Climate Change
Understanding the use of ice-core data will also provide links to environmental
science and rich opportunities for interpreting graphs and data.
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How much radiation is safe?
Whether ionising or non-ionising radiation, the answer is ‘it depends’. In
science we aim to be able to identify the risks associated with any decision
taken, and to monitor and manage the risk. Decisions taken in science often
have to take into account the risks and the management of risks against
potential benefits.
The effects associated with exposure to radiation can be divided int o two
categories: stochastic and deterministic. Stochastic effects are those
associated with long-term low levels of radiation exposure over a time scale
of several years. Exposure to low levels of radiation is not certain to produce
an effect as a result of exposure. However, based on the limited data
available, the currently accepted understanding is that there is no threshold
level of radiation exposure below which cancer or genetic effect will not
occur; doubling the radiation dose doubles the probabili ty that a cancer or
genetic effect will occur.
Reflective question for learners
 What are the difficulties associated with identifying the effects of
prolonged exposure to low levels of radiation?
It should be noted that our understanding of stochastic effects is largely
extrapolated from the limited data available in the aftermath of Hiroshima
and Nagasaki.
Deterministic effects are those associated with a high level of radiation
exposure, generally over a short period of time. In the case of determini stic
effects, there is a threshold dose below which effects are not observed and the
severity of the effect is determined by the magnitude of the dose.
The United States Environmental Protection Agency has more detail on
estimating the risk of exposure to radiation, as does the UK Health Protection
Agency.
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Background radiation and limiting radiation exposure
We are all exposed to radiation from natural and artificial sources, which is
present all around us. It is suggested that life on E arth has evolved to cope
with this, and that cells have self -repairing mechanisms to allow them to
survive relatively unscathed. Taking this further, there is some indication,
such as research by the University of Massachusetts, that there is in fact a
role of low-dose radiation in stimulating our immune system. The monitoring
of wildlife in the Chernobyl Exclusion Zone has also revealed differing
abilities of species to repair damage DNA.
This may be an opportunity to assess learners’ knowledge and understanding
progressed through the context by ask learners to suggest possible sources of
background radiation, both natural and artificial. This would also be an
opportunity to explore the technologies used to monitor radiation, eg the
Geiger Muller tube. A simple experiment with balloons can be used to
measure background radiation around the school or college in different
locations.
Understanding background radiation lends itself to progressing to
understanding comparisons of doses (equivalent dose H) in sieverts (Sv) and,
as appropriate to learners, absorbed dose (D) in grays (Gy).
Reflective questions for learners
 In what job roles are individuals most likely to be exposed to ionising
radiation?
 What determines the biological risk of exposure to radiation?
 What are the measures that can be taken to protect individuals from
harmful exposure to ionising radiation in th eir job roles?
 Identify some technologies used for monitoring radiation exposure of
individuals and explain the science behind these technologies.
Sources of information which may be useful in planning learning and
teaching associated with radiation exposure and equivalent dose include:
Radiation Dose Chart
BBC News Banana Equivalent Dose
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