NATIONAL QUALIFICATIONS CURRICULUM SUPPORT
Chemistry
Products from Plants
[NATIONAL 4]
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. Staff
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.
Staff 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/47423.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
Skills for learning, life and work
7
Ideas for learning and teaching
11
Practical investigations
Dyes from plants
Medicines from plants
Vitamins and minerals from plants
Essential oils from plants
14
14
17
19
22
References
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PLANNING FOR LEARNING AND TEACHING PLANTS TO PRODUCTS
Planning for learning and teaching
This advice and guidance is intended for use by staff. The learning and
teaching suggestions are provided for exemplification only and should be
adapted by individuals. It is anticipated that staff will be creative and
innovative in planning approaches to meet the needs of learners .
This advice and guidance suggests ideas for learning and teaching to prepare
learners in the following mandatory course key area:
Plants to Products in Nature’s Chemistry within Chemistry National 4
Progression from this topic may lead to further study of Energy within Fuels
in National 4 or Agrochemicals at National 5. Advice and guidance has been
produced by Education Scotland to support learning and teaching of
Agrochemicals.
Interdisciplinary learning is important to allow links to be made across
subject areas and to develop learners’ higher-order thinking skills. Global
citizenship can be developed to promote understanding of the
interdependence between people, the environment and the impact of actions
locally as well as globally. There are also opportunities for using plants as a
context for learning in other curriculum areas, for example:
Geography: The effects of intensive farming, crop rotation and other
agricultural practices on land quality may be investigated in conjunction with
geography.
Business Studies: The marketing of a product from a plant source may be
carried out in conjunction with business studies or as part of an enterprise
activity.
As outlined in the Professional Focus Paper for Chemistry at National 4,
learning will be best when it applies a variety of creative and innovative
approaches to the development of interest and enthusiasm for chemistry.
Chemistry provides opportunities for active and collaborative learning in
creative, relevant, inspiring and engaging contexts. Well -designed
experiences in chemistry will develop learners’ curiosity and problem -solving
and analytical thinking skills, skills for collaborative learning and
independent thinking, and interest and enthusiasm for learning. Learners
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PLANNING FOR LEARNING AND TEACHING PLANTS TO PRODUCTS
should be fully involved in their learning and be given opportunities for
personal achievement in order to help build motivation, resilience and
confidence.
Concept development
Chemistry National 4 is designed to articulate with learning and teaching
within the Broad General Education. There are also clear links to Biology
National 4/5 (Food security), Chemistry National 5 (Agrochemicals) and
Science. Topical science can also be linked to this area of chemistry. Staff
should also refer to the Concept development in the sciences paper, which
provides more depth to each line of development.
The Plants to Products topic may allow progr ession from the third level
experience and outcome: I can participate in practical activities to extract
useful substances from natural resources. (SCN 3-17b)
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PLANNING FOR LEARNING AND TEACHING PLANTS TO PRODUCTS
This advice and guidance should be adapted by staff to allow learners interests to be developed upon. The mind map below
includes some ideas that may be of interest to learners.
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SKILLS FOR LEARNING, LIFE AND WORK
Skills for learning, life and work
Learners should experience a range of approaches that are designed to
develop knowledge, understanding and the skills required for learning, life
and work. These should be experiential and learner led. An investigatory
approach is encouraged in chemistry and a holistic approach should be
adopted to encourage simultaneous development of learners’ conceptual
understanding and skills. The study of Plants to Products provides learners
with opportunities to develop their competencies in practical skills, pro blem
solving, critical thinking and working collaboratively. Additional information
is provided in the Course and Unit Support Notes.
Building the Curriculum 4 details the skills for learning, life and work, and it
is envisioned that these should be embedded in Broad General Education and
the senior phase.
The agriculture and agrochemicals industries provide a wide spectrum of
employment possibilities, from council gardeners to PhD chemists, and
therefore the study of this topic can provide links to many occupations.
Partnerships with local agrochemical companies and environmental agencies
could be made to further support learning in this area.
Land-based work offers many opportunities with a wide range of employers
and employer organisations. LANTRA, the Sector Skills Council, states that
production horticulture and agricultural crops provide over 7000 jobs in
Scotland.
A recent report from the Forestry Commission states that over 13,000 people
work within Scottish woods, forests and wood products. The forests, woods
and products contribute over £300 million to the Scottish economy. It has
been calculated that approximately 17% of Scotland's land supports woods
and forests, and 90% of all schools are within 1 km of woodland.
Plant products are also used in the cosmetics industry (eg vitamin E), in the
food industry (as flavourings and colours, such as beetroot extract) and in
perfumes.
Partnerships with local companies (eg cosmetic s or fine chemicals) and
environmental agencies could be made to further support learning in this area.
STEM ambassadors are a useful resource for this and other science topics.
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SKILLS FOR LEARNING, LIFE AND WORK
The importance of current research and development of products from plants
cannot be ignored. New plant products may prove to be a key aspect of
providing food and energy security in Scotland and beyond.
Scientists in Scotland are researching many different ways of using plants as
a source of new products. Plants are being used to develop new, renewable
sources of feedstocks for the chemical industry, for example starting
materials for polymer production and fuel production. Some of these new
products will reduce our reliance on fossil fuel s and other non-renewable
resources. Learners may already be aware of the use of biomass to develop
alternative fuels. Biodiesel can be made from vegetable oils. Alcohol made
from sugars and starches is used to make fuel for cars.
The National STEM centre has developed a teaching resource about biodiesel.
Learners could be encouraged to consider the implications of growing crops
like corn for food or fuel on the biodiversity of our planet. In some countries,
for example Indonesia, huge areas of forests have been cleared to grow one
cash crop to produce palm oil, which is used in cosmetics, toiletries and food.
Open-ended question
Using your knowledge of plants and their uses, give examples of how plants
are being used to help solve some of the world’s problems and explain some
of the problems associated with these uses.
Learners should be made aware that many scientists are currently resear ching
new ways of using plants and plant-based substances. Biomimicry is an
emerging area of research and development that is described in this TED talk.
This short video demonstrates 12 examples of materials that have been
developed using the concept of biomimicry.
Plants are being used to decontaminate soils,
clean the air and clean water. They are being
modified to produce the starting materials
(feedstocks) for some industrial processes.
Plant-based substances like cornstarch are
being turned into biodegradable polymers for
packaging, eg polylactic acid.
Biodegradable plant-derived plastic
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SKILLS FOR LEARNING, LIFE AND WORK
Plants produce a whole range of complex substances that can be used as
alternatives to chemicals. Waxes, fats, proteins and sterols can be extracted
and used in commercial products such as cosmetics.
Some of the challenges we face in the near future, eg the reduction in fossil
fuel supply, pollution and food production, may well be so lved by
innovations in the way we use the natural resources of the plants that grow
around us. Learners should be encouraged to find out about novel materials
and what contribution they may make to these challenges.
Corn – a crop for food or fuel?
Food from plants – bread, bioethanol fuel pump
The Course and Unit Support Notes for Chemistry National 4 suggest skills
and techniques that are important in the development of young scientists in
preparation for the world of work.
The study of Plants to Products could provide opportunities for learners to
practise:
 titrations
 safe methods of heating
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SKILLS FOR LEARNING, LIFE AND WORK
 drawing diagrams of apparatus
 using tables to represent data
 representing experimental data using bar or line graphs and sketching lines
or curves of best fit if appropriate
 suggesting improvements to investigations with reasoning.
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IDEAS FOR LEARNING AND TEACHING
Ideas for learning and teaching
The key area of Plants to Products provides an opportunity for a number of
learning activities that could enhance practical and investigative skills while
providing a context for scientific research and ICT activity .
This advice and guidance uses medical, health and dye products as
exemplification. As described earlier, this is not an exhaustive list of plant
products and it must be noted that there are many other product types that
could be investigated depending on the interests of learners. Alternatively,
staff may prefer to consider this topic within another key area, eg acids and
alkalis.
Card sort exercises could be used as an introduction to the topic. Learners
could be shown a variety of consumer products containing plant-based
substances.
There are numerous examples, including but not limited to:
vegetable oils
paper
tea
coffee
cotton
sugar
flour
shampoo (coconut, lemon)
biodiesel
rice
aspirin
vitamin C tablets
evening primrose oil
natural food colouring
natural flavourings (eg vanilla)
perfume
body lotion (containing cocoa butter, shea
butter, olive oil etc)
vegetable-based soap
rubber
cellulose
It may also be a worthwhile exercise to include products that are not derived
from plant materials.
Learners could categorise the products into self-determined categories and
provide reasons for their choice of categories. As an alternative to this card
sort exercise learners could be provided with pictures of the plants from
which these products are derived and asked to match up the product with the
plant. Using a plant product of choice, learners could research the stages of
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IDEAS FOR LEARNING AND TEACHING
plant to product. This work could be presented in a variety o f ways, with the
learners choosing with negotiated success criteria.
The card sort exercise will allow learners to conclude that plants have many
uses, from cosmetics to fuels. Working collaboratively, learners could rank
the uses in order of importance using a diamond nine exercise.
Learners progressing from the Broad General Education should be familiar
with the process of photosynthesis and the contribution that plants make to
maintaining a CO 2 balance. However, growing plants on an industrial scale
often requires the use of fertilisers, special greenhouses and the use of
chemicals, including pesticides, fungicides and herbicides. Synthetic
fertilisers and pesticides are manufactured in processes that use energy and
other resources. Organic farming uses only natural fertilisers and pest
control.
Learners could be encouraged to consider the issues of sustainability and
renewable resources by the use of reflective questioning. If appropriate, this
learning activity may allow learners to consider the environmental, social and
economic significance of plants grown locally an d/or globally.
Reflective questions
 Plants are renewable resources. What distinguishes a renewable resource
from a finite resource?
 What is meant by the term ‘sustainability’?
 Many plant materials have been replaced by synthetic polymers, for
example nylon rope can replace hemp rope, PVC can replace wood for
window frames. However, most synthetic polymers are made from
substances obtained from crude oil, which is a finite resource. Can you
suggest reasons for the widespread use of oil -based products?
 Using your knowledge of chemistry describe some ways that the use of
plant-derived products could help to minimise climate change .
Learning within this key area will allow learners to become aware that plants
contain a plethora of often complex chemicals essential to industry and to our
daily lives. Learners could be asked to consider the reasons why these
chemicals are produced by plants.
Poisonous plants could be discussed and links to crime writers such as Agatha
Christie could be used to stimulate interest in this topic. The use of digitalis
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IDEAS FOR LEARNING AND TEACHING
as both a poison and a medicine could be a starter for the consideration of
medical testing on animals.
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PRACTICAL INVESTIGATION
Practical investigations
The following experiments have been adapted from the work of SSERC. They
provide examples of how plants and their derivatives can be used. These
experiments should be adapted to meet the needs of learners to allow
progression of scientific skills and offer suitable challenge to all.
Dyes from plants
Learners may have extracted dyes from plants in the Broad General Education
and this should be taken into consideration by staff to ensure progression of
skills and knowledge in this topic.
In ancient times, cloth was dyed using plant -based substances. The roots,
bark, leaves, fruits and wood from certain plants give characteristic colours.
Today, most fabric dyes are synthetic chemicals.
Indigo is a natural dye extracted from the plant Indigofera tinctoria,
commonly known as true indigo. Learners may examine samples of this pink flowered plant to ascertain which part of the plant produces the blue dye. It
was the original dye used to colour denim its characteristic blue. The
chemical structure of the dye is now known and it can be manufactured
synthetically.
Indigo plant
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Denim
PRACTICAL INVESTIGATION
Learners could find out about other traditional dyes , such as henna, and
consider the significance and importance of these dyes in different cultures
past and present.
The dyeing procedure is a straightforward process. A piece of material is
soaked in the dyeing liquid then washed and dried. A mordant is used along
with the dye to make the product colour-fast. In the past, mordants were
natural chemicals such as urine, vinegar and lemon juice.
A procedure for preparing and using dyes is outlined. It is suggested that this
experiment is used as a starting point for an investigatory approach .
The procedure can be adapted in many ways, as suggested below. The plant
dyes have been selected for their availability and safety. Others can be used.
Learners should be encouraged to suggest, risk assess and experiment with
plants of their choosing.
Aim
To prepare natural dyes from plants and test the various properties of dyes.
To allow for the development of experimental skills, learners can be
encouraged to plan and design this experiment.
Equipment
Squares of white fabric
Stirring rod
250 cm 3 beakers
Bunsen burner
Tripod
Heat-proof mat
Plant material
Turmeric powder
Beetroot (boiled or pickled)
Tea or coffee (strong solution)
Blackberries (brambles)
Onion skins
Colour produced
Yellow
Pink
Brown
Purple
Yellow
Mordant (if used)
4 g alum (aluminium potassium sulphate) and 1 g cream of tartar dissolved in
100 ml warm water
Alternative: 100 ml vinegar
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PRACTICAL INVESTIGATION
Safety
As part of planning experiments and investigations learners should be
encouraged to risk assess the planned procedures. This planning stage, in
conjunction with earlier work on plant chemicals , may encourage learners to
consider that ‘natural’ does not necessarily indicate a lack of potential risks .
Goggles
Gloves
Procedure
1.
2.
3.
4.
Prepare ca. 150 cm 3 of dye solution in a beaker.
 Onion skins, beetroot or blackberries can be chopped up and boiled
in water for approximately 10 minutes then the solution strained.
 6 g of turmeric should be added to 150 ml warm water.
 A strong solution of coffee should be made with 25 g of instant
coffee in 150 cm3 water or strong tea made with boiling water, left
to brew then strained.
Prepare the mordant solution and add 50 cm3 to the dye solution.
Alternatively, the fabric can be soaked in the mordant for 30 minutes
and dried before adding it to the dye.
Add the fabric to the warm dye solution. The longer the fabric is left,
the more dye is taken up. It could be left overnight.
Rinse the dyed fabric in cold water and leave it to dry.
Treatment of results
Learners should be given the opportunity to change the basic proce dure
above.
Photographs may be taken of the experimental procedure or samples as
evidence of the process. The technique lends itself to a number of
investigations:
1.
2.
3.
4.
5.
6.
Compare the effect of using the mordant with no t using the mordant.
Compare different dyeing times.
Investigate the effect of washing on dye retention.
Compare a natural dye with a synthetic dye.
Do ‘colour’ washing powders affect dye retention when compared to
other washing powders?
Use the prepared dyes to indicate pH.
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PRACTICAL INVESTIGATION
Reflective questions
Discuss some advantages and disadvantages of using plant dyes instead of
synthetic dyes.
Consider some reasons that people may have wanted to use dyes.
Why do you think more synthetic dyes are used than natural dyes in
manufacturing today?
Medicines from plants
Many medicines in current use are derived from substances found in plants.
Learners could find out about some common medicines that are derived from
plant substances. Since ancient times, people have recognised that chewing
bark or drinking a tea made from certain leaves can help to relieve symptoms
like pain or fever. Scientists have been able to identify many of the active
ingredients of such plants. Once identified, the chemical structure of the
active ingredient can be worked out and the s ubstance can be manufactured in
a laboratory. After extensive testing, the substance may be marketed and sold
as a medicine. This is a costly process for the pharmaceuticals industry.
Aspirin is a well-known example of a useful medicine derived from a pla nt.
As understanding of aspirin's properties has grown, its therapeutic
applications have widened. It first became established as a hou sehold
painkiller and now is considered to be an important medicine in the
management of cardiovascular disease. There is increasing evidence that it
reduces the risk of some cancers and certain pregnancy complications. There
are undesirable side effects of aspirin, including gastrointestinal ulcers and
stomach bleeding. Aspirin medications for children under 16 were banned
because of the risk of Reye's syndrome.
The history of aspirin, from the chewing of willow bark to the isolation of
salicylic acid, is summarised in a booklet from the Royal Society of Chemistry
(RSC) that can be downloaded from their website http://www.rsc.org/learnchemistry/content/filerepository/CMP/00/000/045/Aspirin.pdf
The story of aspirin may be used as a starting point for research around
medicines and their efficacy and testing. Learners could source information
and use it to create a timeline of the development of aspirin. This could be
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PRACTICAL INVESTIGATION
compared to other known drugs. An interesting example of drug use is
thalidomide, which is currently being used for some conditions despite
previous bans.
White willow bark
Aspirin tablet
A useful exercise in which learners can practice their skills of scientific
literacy might be to research a plant-based medicine and consider the
accuracy of the sources of information.
Some of the following questions could be used to form such a research
exercise for learners. Other information could be included by learners.
 What medical conditions is this plant-based medicine used for? Have the
uses changed?
 When was the active ingredient of the plant discovered?
 What is the name of the active ingredient and what is its structure?
 Is the active ingredient still extracted from the plant or is it manufactured?
 What steps are taken by pharmacologists to make sure a medicine is safe to
use before it is sold to the public?
 Are there any side effects of this medicine?
 Can you name any other plant that is used to produce a medicine today?
 How reliable is the information that you have sourced? Is it recent
research?
Learners should present their findings in a suitable format. One method of
presentation could be to use small cards. Working collaboratively learners
could be asked to rank the medicines in order of usefulness.
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PRACTICAL INVESTIGATION
Vitamins and minerals from plants
Lemons – a source of vitamin C
Vitamin E capsules
Learners will be aware that vitamins and minerals are used as food
supplements and may also be aware that both vitamins and minerals can also
be used in topical treatments to help some skin conditions. Some vitamins are
plant derived, for example vitamins A, B, C and E.
Vitamin E is an antioxidant extensively used in skin creams. Shea butter,
avocados and evening primrose oil are rich in vitamin E.
Vitamin A is used in skin creams to help treat skin conditions like acne. It is
present in fruit and vegetables that are yellow or orange in colour.
Selenium is found in Brazil nuts and recent research suggests that selenium
intake is correlated with a reduced risk of breast cancer.
Lack of vitamin B has been linked to increased levels of depression.
Reflective questions
1.
2.
3.
4.
Find out what plants contain vitamins A, B and E.
Some antioxidant vitamins are said to have an anti-aging effect. What is
an oxidation reaction? What evidence is there to suggest that these
vitamins have anti-ageing properties?
Select a vitamin or mineral and find out what specific conditions it can
be used to treat. Consider the effect of too much or too little of the
vitamin or mineral.
Brazil nuts in UK outlets are mainly imported from Bolivia. Consider
the implications of the harvesting of these nuts. Do the health benefits
outweigh the disadvantages of the food miles that are used ?
Vitamin C is needed in the diet for healing and fighting infection. Vitamin C
is also an antioxidant and has been included in some skin products. Fruit and
vegetables are important sources of vitamin C. We can determine the vitamin
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PRACTICAL INVESTIGATION
C content of various food samples by using iodine in a redox reaction. This
experiment can be adapted in a number of ways as an investigation.
The following procedure uses droppers or syringes . Burettes may also be
used.
Aim
To compare the vitamin C content of different fruit juices using iodine
solution.
Equipment
Test-tubes
100 cm 3 beaker
10 cm 3 measuring cylinder
5 cm 3 syringes
Iodine solution, 0.05 mol l –1 (1.27g iodine and 1.5 g potassium iodide made
up to 100 cm 3 with distilled water)
0.1% starch solution
Selection of fruit juices – these can be extracted from fruit, filtered and
volume measured, or bought as fresh juice, from concentrate etc (dark juices
like cranberry will require colour extraction first)
Vitamin C tablet – 1000 mg dissolved in distilled water and made up to 1000
cm 3
Procedure
1.
2.
3.
4.
5.
6.
7.
Arrange the test-tubes in a rack, one for each juice sample to be tested.
Add 4 cm3 iodine solution to each test-tube
Add 1 cm3 starch solution to each test-tube. Mix. The solution will be
blue/black.
Add the fruit juice to the iodine solution using a dropper or syringe.
Mix.
Record the volume of fruit juice required to remove the blue/black
colour from the test-tube.
Repeat for each sample of juice (and the vitamin C tablet) and record
the results.
Present your results in a suitable format .
Note
Some dilution of juices and solutions may be required to obtain suitable
results, eg the vitamin C tablet in solution will contain much more vitamin C
than the fresh juices.
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PRACTICAL INVESTIGATION
Learners may discuss the results and the relative vitamin C content of the
samples.
There are a number of possible investigations:
1.
2.
3.
4.
Compare
Compare
Compare
Compare
fresh with ‘from concentrate’ juice.
vitamin C content over time.
the vitamin C content of fresh and cooked samples.
previously cut and stored fruit with freshly prepared fruit .
Suggested questions
Do you think that taking vitamin C tablets would be better than getting
vitamin C from fresh fruit or vegetables? Explain your answer.
There is a lot of research into vitamin destruction in foods. Do your findings
agree with published research?
How would you improve the experiment to get more reliable results?
There is an opportunity to evaluate the reliability of the sampling of the
juices. Do you measure the mass of the fruit or just the volume of the juice
extracted? Published tables of vitamin C content are expressed in m illigrams
of vitamin C per 100 g of food. Findings can be recorded as an experimental
report, including the discussion guided by these questions.
Learners could use their research and experimental results to prepare a public
information presentation on vitamins and minerals.
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PRACTICAL INVESTIGATION
Essential oils from plants
Evening primrose
Evening primrose oil capsules
Some plant-derived substances are used in cosmetics, toiletries and foods.
Essential oils are pure oils extracted from plant sources. Lavender, rose,
sweet almond and clove oils are commonly available.
There are well-established methods of extraction of essential oils in the
laboratory using distillation equipment. A simple steam distillation is
possible using Quickfit apparatus or test-tubes and a delivery tube.
Extraction of oil from orange or lemon peel or cloves is carried out using
water in a simple distillation. Minimal starting material is required (unlike
the case of rose petals or mint leaves) and the product is highly scented. The
experiment could be followed by a further procedure using the extracted oil
to make a consumer product such as a candle or a lip balm, although this may
require more oil than is produced. An opportunity for interdisciplinary
learning exists here, producing, packaging and marketing a product using a
plant-derived material. Alternatively, research into the manufacture of
cosmetics or toiletries using plant products could be conducted.
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PRACTICAL INVESTIGATION
Aim
To extract essential oils from orange or lemon peel .
Equipment
Quickfit apparatus can be used for this experiment. Alternatively, a boiling
tube, delivery tube and test tube could be used.
Bunsen burner
Tripod
Ice
250 cm 3 beaker
Anti-bumping granules
Stand and clamp
Orange or lemon peel (fresh or dried)
Paper towel
Distillation equipment
Procedure
1.
2.
3.
4.
Chop up and mash about 15 g of orange peel (try to avoid any white
pith) with 20 ml water.
Put the peel and water in a boiling tube or round-bottomed flask with
some anti-bumping granules.
Set up the distillation apparatus as shown in the diagram. (Use a paper
towel soaked in cold water wrapped around the delivery tube as a
condenser if not using Quickfit apparatus.)
Use a low Bunsen flame or electric heating mantle to gently boil the
water.
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PRACTICAL INVESTIGATION
5.
6.
Collect about 15–20 ml of condensate (the liquid in the test-tube).
The steam should condense in a test-tube or beaker set in ice. The
condensed liquid should contain essential oil from the peel. The oil
should be seen as a thin layer above the water and have a strong smell
of citrus.
This is a simplified version of steam distillation. Normally the peel would be
separated from the steam by a plug of glass wool so that the steam passes
over the mashed up peel. If the oil is not to be collected for further use, eg to
make lip balm, this method, without the glass wool, works well.
Carrying out a distillation and drawing the apparatus are both skills required
at National 4.
The following RSC resource has a method for steam distillation and a number
of suggestions for the use of the prepared essential oils, including making lip
balm. It includes help with cost analysis, packaging and marketing. This may
offer a good opportunity for an interdisciplinary learning project.
http://www.rsc.org/learn-chemistry/resource/res00000790/wash-bagchemistry
Extraction of the essential oil limonene from oranges. The poster presentation
can be used by learners as a template for a poster.
www.reading.ac.uk/web/FILES/chemistry/Limonene.pdf
Article about using essential oils in aromatherapy.
http://www.cancer.gov/cancertopics/pdq/cam/aromatherapy/healthprofessiona
l/page3
Lip balm containing essential oils
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Skin cream
REFERENCES
References
Resource discussing how plants are used to produce useful products.
http://www.rsc.org/learn-chemistry/resource/res00000875/challenging-plantsproducts-from-plants
Article about extracting waxes from plants and using them to make polymers.
From waxes to riches, J. Clark and F. Deswarte, Education in Chemistry Vol.
45, Number 3, p 76, 2008.
www.rsc.org/Education/EiC/issues/2008May/Index.asp
Article about food vs fuel debate.
http://www.google.co.uk/url?sa=t&rct=j&q=guardian.co%2Fuk%2Fcommenti
sfree%2F2012%2Faug03%2Famerica&source=web&cd=1&sqi=2&ved=0CFAQFjAA&url=http%3A%2F%2Fwww.
guardian.co.uk%2Fcommentisfree%2F2012%2Faug%2F03%2Famer icancorn-feed-people-notcars&ei=saEfULrCAdLa0QWX34HQCg&usg=AFQjCNHNedXDf_Rk_FqOU
RvwBgE47GtgPA
Article discussing fears that using corn as fuel will raise food prices.
http://www.google.co.uk/url?sa=t&rct=j&q=http%3A%2F%2Fnytimes.com%
2F2011%2F04%2F07%2Fscience%2Fearth&source=web&cd=1&sqi=2&ved=
0CFIQFjAA&url=http%3A%2F%2Fwww.nytimes.com%2F2011%2F04%2F0
7%2Fscience%2Fearth%2F07cassava.html&ei=zaAfUKWoGYel0AWy94HIC
Q&usg=AFQjCNF39JsC7DhIAfNILCsKFLpx1Brpmg
Natural balance – threats to the rainforest. Short video (4.33 minutes)
discussing the problem of sustainability in Brazilian rainforests.
http://www.bbc.co.uk/learningzone/clips/natural-balance-threats-to-therainforest/4712.html
Article on making plastic from plants
http://www.rsc.org/chemistryworld/News/2010/November/2511 1003.asp
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REFERENCES
Article from Scientific American about the process of producing fuel from
crops such as soya bean.
http://www.google.co.uk/url?sa=t&rct=j&q=using%20plants%20to%20make
%20fuel&source=web&cd=1&sqi=2&ved=0CFcQFjAA&url=http%3A%2F%2
Fwww.scientificamerican.com%2Farticle.cfm%3Fid%3Dusing -plants-insteadof-petroleum-to-make-jetfuel&ei=TaIfUK6MBcjV0QWk6YHwCg&usg=AFQjCNHkkbr -hBhjJ0_kyr9f5lSx57qfg
Article about using plants to clean water.
http://search.mywebsearch.com/mywebsearch/redirect.jhtml?searchfor=using
+plants+to+clean+polluted+water&cb=YW&n=
77C09F4F&qid=069c8564007a4acf85c1048b6c2d154a&ptb=53D4EF8FCD57-4AD0-823A92A918782421&id=YWxdm002YYgb&pg=GGmain&ptnrS=YWxdm002YYg
b&action=pick&ss=sub&pn=1&st=hp&pr=GG&tpr=hpsb&redirect=mPWsrdz
9heamc8iHEhldEScnQP%2Byj1AwJX6DKOFr8FbQAHz7FZOu6%2BCv0pM
SS8p3rLkQqkWeCokhY2MOFXmxgE%2BThF3bpeeUjgxti p%2FwEHnhIWS
nV8ZNmw%2BWsqRjo4I3%2Bklj7Lfr3DI8cvi1dwL88Q%3D%3D&ord=5&ct
=AR&
Factsheet from Rainforest Action Network
http://ran.org/problem-palm-oil-factsheet
More experiments for dyes.
http://www.open.edu/openlearn/science-mathstechnology/science/chemistry/diy-experiments-natural-dyes
You choose the news allows learners to create their own news stories from a
bank of clips. The news stories are judged to be balanced or unbalanced and
learners can consider bias in the media
http://www.hutton.ac.uk/learning/games-resources/you-choose-news
A short article giving the recent history of aspirin.
http://www.telegraph.co.uk/health/healthnews/8184625/History -ofaspirin.html
Workbook on aspirin that may be useful for background information.
http://www.rsc.org/learnchemistry/content/filerepository/CMP/00/000/045/Aspirin. pdf
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PRODUCTS FROM PLANTS (NATIONAL 4, CHEMISTRY)
© Crown copyright 2012
REFERENCES
Book containing the method for the vitamin C/iodine experiment.
Contemporary Chemistry for Schools and Colleges , Vanessa Kind, RSC, 2004
Information about the vitamin content of foods.
http://www.naturalhub.com/natural_food_guide_fruit_vitamin_c.htm
Information about fat-soluble and water-soluble vitamins.
http://www.bbc.co.uk/health/treatments/healthy_living/nutrition/dietary_vitfa
t.shtml
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