Student supplement
www.rsc.org/eic
November 2009 • volume 46 • Number 6
Acid attack
Rising CO2 levels
threaten sea life
ISSN 0013-1350
GCSE criteria
Plastic waste
Consultation calls for more
clarity on assessment regimes
Chemists look to Nature for
greener alternatives
Issue 119 november 2009
Jupiterimages
Stone-faced chemists
York Minster, the 15th century
limestone cathedral, has over the
centuries suffered much erosion as
a result of weathering and
pollution. During this time
restoration work has been done,
some of which has been more
successful than others. Now, in
what is the latest phase of such
work, archaeologists from the
University of York have teamed up
with chemists from the University
of Cardiff in an attempt to restore
the east front of the cathedral.
By using a range of X-ray
techniques, the chemists are
providing detail on the
microscopic composition of the
limestone, historical mortars and
the decay products. This
information should give the
conservators the edge when it
comes to deciding how to treat
the stone, and importantly should
ensure that in their efforts to
preserve history they do not cause
further damage.
In contrast to intact sections of
the limestone, the chemists, led by
Dr Karen Wilson, found that the
decayed areas comprised high
levels of calcium sulfate (gypsum).
She told InfoChem, ‘This probably
originates from the industrial era
when there were high levels of
sulfur dioxide in the atmosphere,
though it could also be something
inherent in the stone. The results
importantly indicate that any
building materials used to restore
the stone should have low sulfate
understanding a phenomenon
that has bugged archeologists for
some time, ie the faces of stone
that experience the worst decay
are in sheltered areas, while the
most exposed areas don’t tend to
weather as much. Wilson
explained, ‘One of the properties
of calcium sulfate is that it is
sparingly soluble, so surfaces that
are exposed to rain will have the
salt washed off, but in sheltered
regions the salt can accumulate
and crystallise out, which kicks off
the decay mechanism’. This
content’. Some of the mortars that information is relevant to the
current work since the east face is
were used in the past, Wilson
explained, contained high levels of now covered with scaffolding,
which is expected to stay up for
sulfate ions, which washed into
between five to 10 years.
the stonework and led to decay.
What will be used to treat and
The limestone used to build York
repair the limestone will depend
Minster is dolomite – a mixed
on the results of the analytical work
calcium–magnesium carbonate
done by the chemists. However,
(CaCO3.MgCO3). The stone has a
this is likely to take the form of a
rich cream colour and is easy to
surface coating that can be
carve but is also vulnerable to
decay. Wilson pointed out that the washed off and eventually
replaced.
dolomite used contained trace
The chemists are using X-ray
amounts of certain catalytic
diffraction to confirm the structure
impurities, such as iron, which
of crystalline compounds and
would speed up the decay
X-ray absorption spectroscopy to
process.
look at the structure of any
The chemists are also closer to
amorphous compounds present,
Signs of decay…
such as silicates. They are using
X-ray electron spectroscopy to
look at the composition of surfacespecific species. The latter
technique has the advantage that
it also provides information on the
element’s oxidation state.
York Minster – a
national treasure
Download a pdf of this issue at: www.rsc.org/EiC
InfoChem_Nov09.indd 1
IN THIS
ISSUE
Vitamin D
Are we getting enough of
the sunshine vitamin?
A day in the
life of…
Celia Gitterman,
technical editor
On-screen
chemistry
Check out fuel cells in
'eco' hotel
Backyard
chemistry
How to trap a soap
bubble…
Plus…
Prize puzzles
Editor
Kathryn Roberts
Assistant editor
James Berressem
Design and layout
Dale Dawson
Infochem is a supplement to Education
in Chemistry and is published
bi‑monthly by the Royal Society of
Chemistry, Burlington House,
Piccadilly, London W1J 0BA, UK.
020-7437 8656, e-mail: [email protected]
www.rsc.org/Education/EiC/index.asp
© The Royal Society of Chemistry, 2009
Published in January and alternate
months. ISSN: 1752-0533
1
19/10/2009 11:21:27
­­­The sunshine vit
Issue 119 november 2009
Vitamin D is often called the sunshine vitamin because it is made as a direct result of
ultraviolet rays from the sun falling on our skin. Essential for a healthy skeleton, there
is now some evidence that a deficiency in this vitamin could lead to illnesses as diverse
as cancer, diabetes and flu. So what is vitamin D, why is it so important, and what
evidence is there to link it to such a range of illnesses?
V
itamin D is a group of fat
soluble compounds which
have structures based on
steroids, ie contain four
connected carbon rings. Two
types, D2 (1) and D3 (2), are found naturally in
the diet, while D3 can also be synthesised in
the body if the skin is exposed to ultraviolet
light with a wavelength of between 290 and
315 nanometres (ie UV-B). On absorption of
UV-B, the compound 7-dehydrocholesterol,
which is common in skin cells, rearranges to
form the energetically more stable D3 (see
equation (i)).
Once formed, vitamin D3 is converted by
enzymes in the liver and kidney to the more
active 25-hydroxyvitamin D (25(OH)D). This
compound – a hormone – works together
with specific proteins to allow effective
transport of calcium and phosphate ions
Jupiterimages
Jump for joy… sunshine and healthy bones
2
InfoChem_Nov09.indd 2
through the blood. A lack of this compound
reduces the uptake of these ions from the
intestine and creates a shortage for bone
growth. (Bone is made up of a network of
collagen fibres impregnated with crystals of
hydroxyapatite, Ca5(PO4)3(OH).)
Vitamin D deficiency
A shortage of vitamin D leads to rickets in
children and osteomalacia in adults, both
characterised by soft, deformed bones which
cannot support the weight of the body. At the
beginning of the 20th century, over 80 per
cent of children in the industrial cities of
northern Europe and north-east US had
rickets – partly because of poor diet but also
because they weren’t getting enough sunlight
to compensate.
Nowadays rickets is much less common
because vitamin D is added to various foods,
and more people are aware of the benefits of
a balanced diet. Oily fish is the most important
dietary source of vitamin D, containing 5–10
micrograms (μg) per 100 g. Other sources
such as margarine, some breakfast cereals, red
meat and egg yolks, have lower levels, from
1–8 μg per100 g. The recommended daily
allowance of this vitamin for 14 –18-year olds
is 5 μg per day in the US, while in the UK 10 μg
per day is recommended for certain ‘at risk’
groups such as pregnant and breast-feeding
women.
Around 90 per cent of our vitamin D
requirement is made in our skin, with just 10
You may copy this page for use within schools
19/10/2009 11:26:02
vitamin
BIOPHOTO ASSOCIATES/SCIENCE PHOTO LIBRARY
per cent coming from the diet. And herein lies
a potential problem. The amount of vitamin D
that can be synthesised in the body will be
subject to seasonal variations in sunlight. Not
a problem if you live in the tropics, but in
winter, at latitudes above 52º north, ie
northern Europe and north-east US, the light
does not contain enough UV-B to rearrange
the vitamin D precursors in the skin.
Elina Hyppönen, a research scientist in
epidemiology at the Institute of Child Health
at University College London (UCL) is
interested in the role that a vitamin D
deficiency may have in various illnesses. She
explained to InfoChem, ‘Owing to a lack of
UV-B in northern latitudes many people in
these regions will have low levels of vitamin D
in the winter. To prevent severe vitamin D
deficiency we need to have concentrations of
25(OH)D above 25 nanomoles per litre
(nmol l–1) in the body’.
According to Hyppönen 15 per cent per
cent of the Caucasian population in the UK, for
example, has below 25 nmol l–1 of 25(OH)D in
the winter and around 90 per cent has less
than 75 nmol l–1 which is still considered to be
less than optimal. People with darker skin
pigmentation have potentially lower levels
because the natural pigment melanin acts as
a sunscreen and reduces UV-B induced
vitamin D production in the skin. While not
low enough to produce rickets or
osteomalacia, she and her team are currently
investigating the possibility that such levels
might be linked to other health problems.
HO
Causal links?
Hyppönen told InfoChem, ‘In our group we
have looked at associations between infant
vitamin D supplementation and the risk of
developing diabetes during the next 30
years of life'. The team recorded the occurrence
of diabetes in 12 000 people born in Finland in
1966. ‘What we saw was that children who took
vitamin D supplements regularly had an 80 per
cent reduction in their risk of developing
diabetes’, explained Hyppönen. The researchers
also found a link between vitamin D deficiency
and increased incidence of diabetes. ‘It doesn’t
prove it is causal, but it was a consistent
HO
7-Dehydrocholestrol
with steriod structure
shown in red
UV-B light
HO
Previtamin D3
Spontaneous
rearrangement
HO
(1) Vitamin D2
You may copy this page for use within schools
InfoChem_Nov09.indd 3
(i)
(2) Vitamin D3
Bent bones – sign of rickets
association,’ said Hyppönen.
Other researchers are looking at the link
between vitamin D in the body and the
development of cancer, tuberculosis,
cardiovascular disease and even flu. It may be
more than a coincidence that flu increases in
autumn and winter – when levels of 25(OH)D in
the body are lowest. However, Hyppönen
cautions, ‘while it is a very interesting hypothesis,
more research is needed to prove that vitamin D
deficiency is indeed the cause for these
variations.’
She pointed out that it is too easy to jump
to wrong conclusions about what causes
disease, since several health problems are
often interlinked. Obesity, she explained, is a
common factor in the development of many
diseases, including diabetes and
cardiovascular disease. In addition, obese
people are more likely to be vitamin D
deficient, since vitamin D is fat soluble and
tends to accumulate in body fat rather than
being circulated round the body. ‘If you think
about the associations between vitamin D
concentrations and obesity and all the
conditions linked with obesity, you could
draw the wrong conclusions. We need to be
careful otherwise we will make wrong
assumptions simply through association’.
A good way to prove the role of vitamin D in
disease is through controlled clinical trials,
where volunteers are randomly given one of a
choice of ’treatments‘, which in this case would
either be a vitamin D tablet or a look-a-like
tablet that didn’t contain the vitamin (a
placebo). So long as enough people are tested,
explained Hyppönen, this is a reliable method
for determining the effectiveness of the
treatment.
»
3
19/10/2009 12:39:53
“… 90 per cent of our
vitamin D requirement
is made in our skin…”
Issue 119 november 2009
»
One feature of vitamin D biochemistry, said
Hyppönen, is that those receptors (proteins)
which bind specifically to 25(OH)D exist in many
parts of the body, which suggests
widespread influence.
Also
vitamin D is
unusual in that it
can affect the
chemical pathways
leading to infectious
diseases, such as flu, and
diseases like diabetes
which are caused by an
overactive immune system.
Winter supplements?
What is clear is that vitamin D deficiency is
common in northern Europe and northern
parts of the US, and unlike other vitamins and
nutrients, which can be obtained mainly from
the diet, this is not the case with vitamin D.
Research points to around five–10
minutes of sunlight,
between 10 am and
3 pm daily from spring
to autumn as
adequate to
prevent
vitamin D
deficiency for
people with
Bone meal?
light skin. However, while the Food Standards
Agency finds that ‘most people should be able
to get all the vitamin D they need from their
diet and by getting a little sun’, Hyppönen is
more cautious. ‘Since it is difficult to obtain
sufficient vitamin D from the diet, I would
recommend vitamin D supplements during
the winter and at times when you receive little
natural light.’
Tom Bond
magnificent molecules
Tom Bond, postdoc at Imperial College London, highlights his favourite molecules. In this issue: capsaicin
istockphoto; jupiterimages x2
Capsaicin (1) is responsible for the
hot taste of chilli peppers. It can also
relieve pain, is used in pepper spray
and as a performance-enhancing
drug for horses, so it certainly
qualifies as a magnificent molecule.
Chilli plants produce several
similar chemicals called
capsaicinoids, the commonest is
capsaicin. When capsaicin contacts
human tissue, it produces a burning
feeling because the molecule binds
to a protein on the surface of nerve
cells that register heat. The hot
sensation causes the release of
CH3
O
HO
4
InfoChem_Nov09.indd 4
pain-relieving chemicals
(endorphins) in the brain.
Endorphins also produce feelings of
exhilaration, which may explain why
some people find hot food addictive.
The Scoville scale is used to assess
the ‘heat’ of chillies. Originally a test
using a panel of human tasters, now
high-performance liquid
chromatography (HPLC) provides a
numerical analysis. In the HPLC
method warm ethanol is used to
extract the capsaicinoids from the
chilli which are then separated,
identified using an ultraviolet detector,
O
CH3
N
CH3
H
(1) Capsaicin
and their concentrations measured.
Tabasco sauce registers from 2500–
5000 on the Scoville scale and the
hottest chilli ever, a Naga Jolokia, or
King Cobra chilli, over one million.
Should you eat a Naga Jolokia,
drinking water will do little to ease
the pain. This is because capsaicin
is a hydrophobic molecule, with a
low solubility in water. Instead, milk
is an effective calming agent since
it contains casein, a fat-loving
molecule which can help dissolve
the fat-like capsaicin.
Capsaicin-containing creams can
give pain relief from conditions
such as arthritis and shingles.
Meanwhile, in the show jumping
competition at the last Olympics,
five horses tested positive for
Chilli peppers
– hot stuff
capsaicin and were disqualified.
When applied as a lotion to a
horse’s legs, capsaicin acts as an
irritant which causes the horse to
jump higher. n
You may copy this page for use within schools
19/10/2009 11:28:30
Jonathan Hare asks…
Fuel cells: would they blow up
an 'eco' hotel?
In the Bond film Quantum of solace, a dodgy
South American dictator, General Medrano, is
negotiating a deal with the evil Dominic
Greene who wants to take control of one of
the biggest sources of fresh water in the
world.1 The secret deal is signed in a hotel in
the middle of the Bolivian desert. This
state-of-the-art ‘eco’ hotel is powered by fuel
cells. There is a scene where the general is
discussing the merits of the beautiful hotel
and jokingly asks if the fuel cells are safe.
Meanwhile Bond finds out about the secret
meeting and in an action-packed series of
events puts an end to the plot and destroys
the hotel by blowing up the fuel cells. So how
do fuel cells work, are they dangerous and
could they blow up a hotel?
COLUMBIA/DANJAQ/EON/THE KOBAL COLLECTION
Fuel cell technology
A fuel cell is an electrochemical device that
produces electricity from the reaction of a
fuel (on the anode side) and an oxidant (on
the cathode side).2 There is great interest in
using hydrogen as a ‘green’ fuel for fuel cells
since its reaction with oxygen (air) only
produces water as waste. Hydrogen can be
made from hydrocarbon fuels but
unfortunately CO or CO2 are often produced
in the process, and CO2 is a greenhouse gas.3
However, solar cells can be used to provide
electricity to split water into hydrogen and
oxygen in a process known as electrolysis.
Fuel cells are ideal for remote locations and
where a non-polluting energy source is
required. For example, they have been used
to great effect in the space flight programmes
where the H2 and O2 rocket fuel can be
converted directly into electricity and also
water. Unlike a battery, which has to be
recharged regularly, a fuel cell can produce
electricity so long as it has a fuel supply.
‘ECO’ hotel
Going back to the film it appears that there
are several fuel cell units powering the rooms
of the hotel. It’s not clear if each of these units
has its own hydrogen fuel tank or if they are
fed by one large tank. In this remote location,
in the sunny desert, solar cells could be used
to electrolyse water to make hydrogen which
could be stored in tanks for the fuel cells. If
these tanks were ruptured the hydrogen
would vent into the air producing a highly
explosive mixture.4
The minimum ignition energy for H2/O2
mixtures is very low (0.011–0.017 mJ), about
a tenth that of other fuels such as methane
(ca 0.3 mJ) or petrol (ca 0.8 mJ). Even small
electrostatic sparks from certain types of
clothing can cause an explosion. Also the
range of H2 concentrations that can explode
and even detonate is extremely wide, much
wider than almost any other fuel.4
Design fault
At one point in the film a car smashes into a
fuel cell unit which starts a series of
explosions to propagate around the whole
complex that eventually cause the
destruction of the hotel. So based on what
we know about fuel cells what we see
unfolding in the film looks plausible, but
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InfoChem_Nov09.indd 5
Bond checks out early
perhaps only if the hotel design was so poor
that a chain reaction of hydrogen tank
explosions could occur. One thing is for sure,
any survivors of the devastation would have
had major hearing problems afterwards.
References
1. Quantum of solace, Columbia, 2008.
2. For information on fuel cells see: http://en.wikipedia.org/wiki/
Fuel_cells
3. For example, see: InfoChem, 2009, no 114, p 5.
4. Fuel cells: understanding the hazards, control the risks. Sudbury:
HSE Books, 2004.
Dr Jonathan Hare, The CSC Centre, chemistry
department, University of Sussex, Brighton BN1
9ET (www.creative-science.org.uk/TV.html).
Did you know?
Did you know that it was British
scientist Sir William Grove who
discovered the principle on which
fuel cells are based? In 1839 he
observed that after switching off
the current he had used to
electrolyse water, a current flowed
in the opposite direction – produced
by the reaction of H2 and O2 which
had been adsorbed onto the
platinum electrodes.
5
19/10/2009 11:29:12
Dr Hal SoSabowSki preSentS experimentS you can Do on your own
Issue 103 MARCH 2007
In this issue: the colours of soap bubbles
Soap bubbles are difficult to examine
because of their fragility and short life.
However, because they are very light, they
will float on a gas, such as carbon dioxide,
that is only slightly denser than the air that
fills them. When soap bubbles settle into a
container of carbon dioxide, the bubbles
float on the carbon dioxide and can
therefore be examined closely.
materials
You will need:
●● soap bubble solution with blowing
wand;
●● a large transparent container with an
open top such as an empty fish tank;
●● 125 ml (half a cup) of baking soda
(sodium hydrogen carbonate);
●● 250 ml (1 cup) vinegar;
●● shallow glass dish to fit inside the large
container such as a glass baking dish.
Method
Matthew J. Ingram
Place the glass dish inside on the bottom
of the large transparent container. Put
125 ml of baking soda in the glass dish.
Pour 250 ml of vinegar into the dish with
the baking soda. The mixture of soda and
vinegar will immediately start to fizz as
they react and form carbon dioxide gas.
Carbon dioxide is denser than air and will
be held in the large container as long as it
is not disturbed by draughts of air over the
container.
Once the reaction has subsided (about
a minute), gently blow several soap
bubbles over the opening of the large
container, so that they settle into the
container. This may take a bit of practice.
Do not blow directly into the container
because you will blow the carbon dioxide
6
InfoChem_Nov09.indd 6
out of it. When a soap bubble settles in the
container it will not sink to the bottom, as
it would have done in air. Instead, it will
float on the surface of the invisible carbon
dioxide in the container.
While the bubbles are floating on the
carbon dioxide in the container, you can
observe them. Note: their colour(s); their
size and any changes; and whether they
rise or sink. When you have finished,
dispose of the mixture in the glass dish by
rinsing it down the drain with water.
The science
The colours of a soap bubble come from
reflections of the white light that falls on it.
White light, such as from the sun or from a
light bulb, contains light of all colours.
Light travels as waves, and the length of a
wave, from crest to crest, determines the
colour of the light.
When light hits a soap bubble, some
will be reflected from the outer surface of
the soap film, while some light will
travel through the film
and be reflected from
the inside surface of the
film. Waves of light
reflected from the inner
and outer surfaces of the
soap film can interfere
with each other. Where
the crests of the light
waves meet, the intensity
of the light increases. But
if the crest of a wave
meets the trough of
another wave, the
intensity of the light is
diminished.
Whether the crest of a
wave meets another crest or a trough is
determined by the length of the wave and
by the thickness of the film. If the film
thickness is a multiple of the wavelength
of the light, the crests of waves reflected
from the inner surface will meet the crests
of waves reflected from the outer surfaces.
If the thickness of the film is an odd
multiple of half the wavelength, the crests
of the waves reflected from the inner
surface will meet the troughs of the waves
reflected from the outer surface. Because
the thickness of the film varies and the
wavelength of the light determines its
colour, different areas of the bubble will
have different colours.
Health and Safety
Soap can make hard floors slippery.
Acknowledgement: adapted with permission
of Professor Bassam Z. Shakhashiri, University
of Wisconsin–Madison, www.scifun.org/
HomeExpts/homeexpts.html
You may copy this page for use within schools
19/10/2009 11:30:02
A day in the life of…
Technical editor:
Celia Gitterman
Celia Gitterman has spent the past four years working
for the Royal Society of Chemistry as a technical editor.
She talks to Tom Bond about her typical day.
As part of its activities the Royal Society of Chemistry (RSC)
publishes 27 journals, which are made up of articles submitted by
chemists. Over 120 people work on these journals in the RSC’s
Cambridge office. Each article is accepted for publication by a
journal’s editor based on positive comments received from experts
with knowledge of the subject area. Part of the informatics
department and working in a team of 10 staff responsible for six
journals, Celia’s job is to make sure the accepted articles are ready to
be published on the Internet and in print.
Journals production
Working from nine to five each day, Celia edits and proofs the
accepted articles, and compiles these into issues of the journals.
When articles have been accepted for publication, electronic
versions of the manuscripts are sent to typesetters in India, who
convert them into an XML (extensible markup language) format. In
this format different types of text (eg italics, bold, captions
references etc) are marked in different colours, which helps Celia as
she edits the article. ‘When editing the text, we check the spelling,
the references and that it makes
pathway to success
●●
2004–present, technical editor, Royal
Society of Chemistry, Cambridge
2000–04, PhD in organic chemistry at
University of Cambridge
1996–2000, MSci in natural sciences at
University of Cambridge
1994–96, chemistry, maths, physics
A-levels, Sacred Heart of Mary Girls’ School,
Upminster
●●
●●
●●
You may copy this page for use within schools
InfoChem_Nov09.indd 7
Celia Gitterman
sense’, she explains.
Using her knowledge
of chemistry to understand the articles, Celia spots any mistakes in
the chemistry and adds corresponding queries for the authors to
address on the final proof. Graphics, eg illustrations, diagrams etc, in
the article go through a similar process as the text and she also
verifies that these are the correct size to be reproduced clearly in the
final version. Celia takes up to a couple of hours to edit a short,
four-page article. Review articles, which summarise research in a
particular area of chemistry, take longer to edit since these can be
up to 25 pages.
Proofing papers
Once Celia is happy with the edited article, she uses software to
generate a proof of the article similar in appearance to the final
version but which includes questions for the authors on any
sections she is uncertain of. This is sent to the authors by e-mail and
when they return the proof, she includes their corrections in the
final article. She then makes a final check of the article’s content and
layout before publishing it on the Internet in HTML (hyper text
markup language) format.
When the HTML version of the article is published, the typesetters
create a PDF (portable document format) file which is used for the
print and electronic versions of the issue. The journals Celia works
on are published either weekly or monthly and it is her role to
collect articles and combine them to form an issue of a particular
journal. This is called makeup and takes between half a day and a
day. ‘We check the layout of the PDFs for the issue. If everything’s
fine we’ll publish the electronic issue. Then the PDFs get sent to the
printers’ for the print issue’.
Celia edits and proofs about five articles per day. As and when
required she spends some of her day creating ontologies for
chemical reactions. These are like dictionaries to define reactions to
which links can be added in the HTML versions of the articles.
Attention to detail
‘You have to be quite picky to do this job, and it helps if you enjoy
reading’, says Celia. For her it’s very satisfying to edit a manuscript
and spot changes that help to make the chemistry clearer. n
7
19/10/2009 11:30:31
£50 of HMV tokens to be won!
Issue 119 november 2009
Elemental England
This issue Benchtalk brings you a puzzle that links chemistry with geography, contributed by
Antonio Joaquín Franco Mariscal of IES Javier de Uriarte, Cádiz, Spain, and María José Cano
Iglesias of the University of Cádiz, Spain. You must spell the names of 25 cities and towns of
England shown in the map by using the symbols of the elements of the Periodic Table and
isotopes of hydrogen provided in the clues. (Some symbols may need to be used more than
once in a clue.) Please send your answers to: the Editor, Education in Chemistry, the Royal Society
of Chemistry, Burlington House Piccadilly, London W1J 0BA, to arrive no later than Monday 7
December. First out of the editor’s hat with all the correct answers will receive a £50 HMV token.
1. _ _ _ _ _ _ R _ (fluorine, boron, deuterium,
oxygen, radium).
calcium, nitrogen, sulfur, tungsten, oxygen,
uranium, phosphorus, yttrium, tritium, thallium).
2. _ _ _ _ _ _ _ (praseodymium, nitrogen, oxygen,
15. LEE _ _ (sulfur, deuterium)
tritium, einsteinium).
3. MA _ _ _ _ _ _ _ _ (carbon, helium, nitrogen,
erbium, sulfur, tritium).
4. _ _ _ _ _ _ _ _ L (oxygen, phosphorus, lithium,
erbium, vanadium).
5. _ _ _ _ _ (erbium, boron, deuterium, yttrium).
6. _ _ _ _ E _ _ _ _ _ _ _ (oxygen, tritium,
potassium, nitrogen, sulfur, rhenium).
7. _ _ L _ _ _ _ _ _ _ _ _ _ (tungsten, hydrogen,
vanadium, oxygen, americium, nitrogen, erbium,
phosphorus, tritium).
8. _ _ _ LE _ (deuterium, uranium, yttrium).
16. _ _ _ _ _ _ EL _ (helium, fluorine, iodine,
deuterium, sulfur).
17. _ _ _ G _ _ _ _ _ _ _ _ H _ LL (uranium,
oxygen, nitrogen, sulfur, potassium, indium,
phosphorus, hydrogen, tritium).
18. _ _ _ _ _ _ G _ _ _ (titanium, nitrogen,
September PRIZE
WORDSEARCH No. 47 winner
hydrogen, oxygen, tritium, americium).
The winner was Matt Cowie from Mintlaw Academy,
Aberdeenshire.
19. LE _ _ _ _ _ _ _
(sulfur, iodine, tritium, erbium, cerium).
The eight-letter word was sunlight.
20. _ _ _ E _ _ R _ (vanadium, cobalt, tritium,
9. _ _ _ M _ _ G _ _ _ (indium, boron, hydrogen,
americium, indium).
yttrium, nitrogen).
10. _ _ A _ _ _ G (deuterium, rhenium, indium).
21. _ _ R _ _ _ _ _ _ _ _ (oxygen, hydrogen,
tritium, nitrogen, phosphorus, americium).
11. _ _ _ _ _ _ L (bromine, oxygen, iodine, tritium,
sulfur).
22. M _ L _ _ _ _ E _ _ _ _ (sulfur, nitrogen, neon,
12. _ _ _ _ _ _ _ _ _ _ _ (phosphorus, oxygen,
thorium, nitrogen, sulfur, uranium, tritium,
americium).
iodine, tritium, yttrium, oxygen, potassium).
13. _ L _ _ _ _ _ _ (thorium, uranium,
phosphorus, molybdenum, yttrium).
24. L_ _ _ _ _ (nitrogen, oxygen, deuterium).
14. _ _ _ _ _ _ _ _ E _ _ _ _ _ _ _ _ (neon,
8
InfoChem_Nov09.indd 8
Find the element
no. 10 winner and solutions
The winner was Nye Farley from Monmouth School.
Clues 7 and 8 were given in the wrong order.
1
n i
t
h
a
l
5
l
6
i
u
m
2
3
p o t
4
s u
23. _ _ _ _ _ (oxygen, tritium, nitrogen, lutetium).
7
25. _ _ R _ _ _ _ _ _ _ (polonium, molybdenum,
9
m a g n e s i
8
a l u
r
y
s
f
e
r
m
i
o
d
s
u
a
o
g e n
r o g e n
i u m
r
d
n
n i u m
thorium, uranium, sulfur, tritium).
Download a pdf of this issue at: www.rsc.org/EiC
19/10/2009 11:30:54