Student supplement
MARCH 2008 • VOLUME 45 • NUMBER 2
Looking at
atoms
Teaching quantum
mechanics
ISSN 0013-1350
A diploma for science
Anti-obesity drugs
What benefit will the new
diploma bring to UK science?
Does chemistry hold the answer
to shifting the pounds?
Issue 109 march 2008
istockphoto
Sweet fuel cell
A new type of fuel cell powered
with glucose derived from biomass
has been developed by Japanese
researchers. Reporting their work in
the Journal of Global Energy (2007,
28, 2950 ), Yutaka Amao and Yumi
Takeuchi of Oita University, Japan,
explain that the experimental
device works by using sunlight to
convert glucose into hydrogen
which powers the cell, and
produces several hundred millivolts.
Fuel cells were invented by British
scientist William Grove in 1842 and
are, put simply, electrical batteries
with a chemical fuel supply that is
converted into electricity.
Theoretically, they produce no
pollutants only warm water and so
are a potential clean source of
power. However, finding
sustainable sources for their
chemical feed will be the key to
their success.
Renewable resources, such as
food waste and managed highenergy crops, are becoming viable
alternatives to fossil fuels. However,
imaginative ways to convert these
materials into useful, electrical
energy are still required. Renewable
biomass resources include starch,
cellulose, sucrose, and lactose.
These complex sugar molecules
can be readily converted to the
much simpler glucose molecule
with little energy cost through
fermentation processes. The
glucose could then be used to
release hydrogen using enzymes. It
is this last
step that the chemists
have focused on to build their
glucose-powered fuel cell.
The device comprises a
transparent conductive glass
electrode coated with a coloured
molecule that can mimic the
natural process of photosynthesis.
This molecule is incorporated into
light-absorbing titania (titanium
dioxide, TiO2). The coating can
absorb energy from
sunlight and release it
into another chemical
layer on the electrode,
which is host to the
enzyme glucose
dehydrogenase.
This is connected
to a platinum
electrode and
the pair is
immersed in a
glucose solution to
complete the circuit.
When light shines on the lightactive electrode enzymes in the
chemical layer are triggered to react
with glucose molecules in the
solution, releasing hydrogen ions.
The dissolved hydrogen ions then
attract electrons from the platinum
electrode, which causes a current to
flow through the wire connecting
the electrodes. David Bradley
Did you know?
If you are starting an engineering-, science- or maths-based
degree at a UK university in 2008, you could win £2000 to
support your studies by taking part in the annual Corti Trust
Science Prize. The Corti Family Trust is a charity dedicated to
encouraging UK A-level students to study science-based
courses in higher education.
To enter the competition you must write a 1500-word essay
based on recent research in your chosen scientific discipline.
The essay should describe how the research was done and its
potential real-world significance. The closing date for entries is
30 April. For further information on the competition and to
download an entry form visit http://cortiscienceprize.org/.
You may copy this page for use within schools
IN THIS
ISSUE
Anti-ageing
creams
Chemistry smoothes
away the wrinkles
A day in the
life of…
Claire Long,
Account executive
On-screen
chemistry
Do onions make good
batteries?
Plus…
Q&A
Go for gold!
Webwatch
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, 2008
Published in January and alternate
months. ISSN: 1752-0533
Anti-wrinkle p
Issue 109 march 2008
The market for skin care products to help combat the signs of ageing is massive, with
global sales projected to reach US $69.6 billion in 2010. But do anti-ageing creams
work and what’s the chemistry behind them?
A
s we get older our skin
begins to show the outward
signs of ageing with more
wrinkles and sagging. There
are numerous factors at
work, including gravity, sun damage (photoageing) and even the way we use our facial
muscles. What is it about the structure and
chemical composition of the skin that is
transformed with age and do skin care
products such as anti-wrinkle creams really
work?
Skin structure
The skin has two main layers – the outer
epidermis which sits on top of the dermis.
Under the dermis is a layer of subcutaneous
(‘under the skin’) fat. The epidermis is made up
of several layers, the deepest being the basal
cell layer where cells continually divide to
produce new skin cells. The number of cells in
the epidermis decreases by around 10 per
cent per decade and they divide more slowly.
Consequently, the epidermal layer can’t repair
itself so quickly, and becomes thinner with
age. By the time a person reaches 70 their skin
can look thin and fragile.
The dermis contains collagen and elastin
fibres, proteins that provide strength and
flexibility. Collagen is made up of three protein
strands wound together in a triple helix,
giving it great tensile strength. Tough bundles
of collagen – collagen fibres – support most
tissues and give cells structure from the
outside. Elastin is an elastic protein that allows
the skin to go back to its original position after
stretching or contracting. It is formed mostly
Imagehit Inc/Alamy
Holding back the years…
You may copy this page for use within schools
potions
of the amino acids alanine, glycine, valine and
proline. The amino acid chains are cross-linked
by another amino acid, lysine, to form large
arrays. As we get older elastin fibres degrade
and the skin loses its elasticity, and the dermis
also produces less collagen. These changes,
along with the loss of subcutaneous fat, result
in wrinkles.
EYE OF SCIENCE/SCIENCE PHOTO LIBRARY
Anti-ageing creams
Cosmetic companies spend large amounts of
time and money researching and developing
new formulations, predominantly creams that
slow down the signs of ageing. There is a wide
range of ingredients used in such creams and
all have different effects on the skin.
Alpha-hydroxy acids (AHAs), such as
glycolic acid (1) and lactic acid (2), and betahydroxy acids (BHAs), such as salicylic acid (3),
are commonly used in anti-ageing creams to
remove dead cells from the surface layer of
the skin. Dr Danka Tamburic, reader in
cosmetic science at the London College of
Fashion, told InfoChem: ‘The acids degrade the
structures (corneodesmosomes) in the
epidermis, which hold cells together, with the
result that the cells (corneocytes) shed easily.
The skin responds by making new skin cells
faster, which temporarily brings about a more
youthful appearance’.
Other types of hydroxy acids used in antiageing creams are polyhydroxy acids (PHAs) –
eg lactobionic acid (4). Scientists have found
that these are less irritating to the skin than
AHAs and the larger number of OH groups
makes them better moisturisers. How well all
these acids work, according to Tamburic,
depends on their concentration. ‘If you use
five per cent lactic acid, it does help in
increasing cell turnover. Anti-ageing creams
normally contain an acid concentration of up
to three per cent (because of the possible
irritancy), so may be less effective at this
concentration’, she explains.
What about
vitamins?
The effect of vitamin A (retinol (5)) on
the skin was found by chance around 30
years ago. Scientists working on formulations containing vitamin A to treat
acne noticed that patients’ skin showed signs
of fewer wrinkles, better colour and a youthful
glow. Tamburic explains, ‘Vitamin A promotes
regeneration of the skin, similar to AHAs, but
at a deeper level using different mechanisms,
and normal cell turnover can be halved from
around 28 to just 14 days’. Vitamin A also
promotes the synthesis of the skin proteins
collagen and elastin by inhibiting the
production of collagenase and elastase – the
enzymes that destroy such fibres.
There are many chemical forms of vitamin
A. The most efficient in skin products is the
acidic form – all-trans-retinoic acid (Tretinoin)
– which is the only anti-ageing active
ingredient approved by the US Food and Drug
Administration, but specifically for use in
prescription skin creams for acne. This is
because Tretinoin has a strong effect on deep
skin layers and could show a range of adverse
effects, so it is classified as a drug, rather than
cosmetic active.
Since all-trans-retinoic acid can’t be used in
commercial anti-ageing products, the second
best thing, explains Tamburic, is the alcohol
form of vitamin A – retinol. It is less efficacious,
but visibly rejuvenates the skin. However,
retinol is unstable, and would change its
structure and efficacy in the product, so
chemists had to come up with alternatives to
produce similar effects. By chemically
modifying retinol they produced the stable
ester, retinyl palmitate. This ester penetrates
the skin, where enzymes break it down into
the active retinol.
Chemists have also used the technique of
microencapsulation to stabilise and protect
the vitamin. This involves packing the
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Skin deep…
unstable active ingredients inside a small shell
(between 1 µm and 0.1 mm diameter), made
up of various polymers. Tamburic points out,
‘Vitamin A is the only active ingredient that
has been proven to reverse the signs of
ageing. However, if you stop using it
everything goes back to the way it was before’.
O
OH
HO
(1) Glycolic acid
O
OH
OH
(2) Lactic acid
OH
O
OH
(5) Vitamin A
OH
HO
O
O
HO
(3) Salicylic acid
HO
OH
OH
HO
(6) Vitamin C
OH
O
HO
O
OH
O
HO
OH
OH
OH
(4) Lactobionic acid
»
“… the market for skin
care products is
massive.”
Issue 109 march 2008
»
Oxidative damage
The skin can also show signs of accelerated
ageing as a result of external factors – uv
radiation (too much sun), smoking cigarettes
and air pollution. Ultraviolet radiation
penetrates the skin, leading to the formation of
very reactive free radicals. Some of these free
radicals have a negative effect on the proteins
in the skin, such as collagen and elastin,
resulting in loss of strength and elasticity.
Vitamins E (α-tochopherols) and C (ascorbic
acid (6)) are added to anti-ageing creams
because they are antioxidants – they mop up
the free radicals. Consequently cells suffer less
damage, which means preventing more
wrinkles.
Like vitamin A, however, vitamins E and C are
unstable, so their ester forms are usually used
in creams. Tamburic points out, ‘if tochopheryl
ethanoate, a stable ester of vitamin E, is used in
combination with ascorbyl-2-phosphate
(derived from vitamin C) it is even more
effective. These compounds penetrate the skin,
where the ester bonds are broken, giving the
active antioxidants. More than one antioxidant
is used because the free radical species have
different reactivities’.
Peptide power
Getting the needle!
Peptides are now used in anti-ageing creams
because they have similar beneficial effects to
AHAs and retinol without the irritation that
may occur with these other ingredients. Short
chain peptides – three to six amino acids – are
the most common and their size means they
do not sit on the skin surface, but can
penetrate into the epidermis. One example is
palmitoyl pentapeptide-3 (Pal-KTTKS), the
pentapeptide which has been proven to
reduce wrinkles/fine lines. The molecule
comprises five amino acids linked together
attached to a fatty acid. The addition of a
lipophilic (oil-loving) fatty acid to the
hydrophilic (water-loving) pentapeptide helps
the molecule penetrate the skin, which is
essentially lipophilic, and stimulate the key
constituents of the skin, including collagen
and elastin. This is important because collagen
production decreases with age and degraded
elastin fibres start to accumulate, causing
further skin damage.
Peptides are also now used to mimic the
‘Botox effect’. Botox is botulinum toxin which
when injected into the skin temporarily
paralyses some facial muscles and reduces or
eliminates wrinkles. Creams containing
peptides can be used as an alternative to Botox.
According to Tamburic, ‘These peptides block
neurotransmission – ie stop the nerve impulses
that cause muscle contraction, so the muscles
relax and you in fact reverse wrinkle formation.
The effect, however, is less visible than the one
achieved by botulinum injection’.
Research chemists will continue to play an
integral part in developing the next generation
of skin care products. With new sophisticated
technologies coming on stream the door is
open for more exciting developments to help
combat the signs of ageing.
John Johnston
magnificent molecules:
fotolia; istockphoto
Kathryn Roberts, editor Education in Chemistry, highlights her favourite molecules. In this issue: invertase
With Easter so close, chocolate
eggs filled with soft, creamy
sugary centres are not far from
my mind. Against this scenario,
the enzyme, invertase, must go
down as a truly magnificent
molecule.
Enzymes are proteins – long
chains of amino acids joined by
peptide (C–N) bonds – that
speed up chemical reactions. The
enzyme invertase is obtained
mainly from yeast but is also
made by bees, who use it to
make honey from nectar. It’s a big
molecule, with a sweet edge. This
is because it is a sucrase enzyme
– it catalyses the breakdown of
table sugar (sucrose) into simpler
Eggs-cellent chemistry
sugars, fructose and glucose,
and water.
In the manufacture of softsyrup together with colourings
centred chocolates, finely milled and flavourings to give a stiff
sucrose is suspended in glucose
mouldable paste. A small amount
of invertase is added and the
paste is coated with melted
chocolate. Over the next couple
of weeks before the chocolates
are sold, the invertase gets to
work and breaks down the
sucrose into glucose and fructose,
which are much more water
soluble than sucrose. The
resulting solid–liquid balance
thus changes, giving a luscious
creamy texture. n
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Jonathan Hare asks…
onion batteries: do they really
work or simply end in tears?
A recent YouTube clip claims that an iPod
can be charged-up by using its charging
cable, a few 100 ml of a sports energy drink
and an onion. The clip has apparently
attracted over five million hits.1 But is it
possible?
The clip shows an onion being drilled in a
couple of places and then left to soak for 30
minutes in a ‘high energy’ sports drink. An
iPod charging lead is connected at one end
to the iPod and the other end (which usually
goes into the AC adapter/charger) is pushed
into the onion.
Now two metals placed in an electrolyte
will produce a potential difference across
them, providing the metals are different.2 So
it’s possible that pushing the plug into the
soaked onion will produce a voltage if the
plug and its pins are of different metals. But
the potential difference won’t be very much,
probably less than 1 V and the current will be
small, a few mA or so, depending on the
surface area.
An iPod requires several 100s mA charge at
a few volts (ca 5 V ). So unless something
unusual is happening within the onion layers
there won’t be enough electricity to charge
an iPod. Why might the authors think the
onion charger would work?
An iPod is basically a specialised computer
with many programs that enable it to
function. One program is the ‘charge battery
and show details on iPod screen’. When the
plug is pushed into the onion, the electrolyte
(a good conductor) completes a crude
electrical circuit that sends a signal to the
iPod. This will either wake it up from its sleep
mode or, if it’s already on, will trigger this
charging program.
I think what you see on the clip is the
residual power in the iPod battery running
the first steps of the charge program on the
iPod screen but probably not actually getting
so far as charging the battery at all.
It’s easy to get fooled since leaving the
onion in place for an hour might well
produce a higher reading on the battery level
meter when you turn it back on again. But
Know your onions…
then so will leaving the iPod unused for a
while. This is because when you stop
draining a battery and give it a rest, it can
recover a little so when you start to use it
again its voltage will also have improved a
bit.
So while you can make electricity using
the soaked onion, it won’t be enough to
charge an iPod.3 I would be delighted if you
can prove me wrong though. One thing is for
certain, it’s a great way of ruining your iPod
charging lead. n
References
1. YouTube: http://www.youtube.com/watch?v=GfPJeDssBOM
2. M. Bullivant and J. Hare, Educ. Chem., 2006, 43(1), 12.
3. Charge an iPod: http://www.tuaw.com/2007/11/14/chargean-ipod-with-an-onion/
Dr Jonathan Hare, The CSC Centre, Chemistry Department,
University of Sussex, Brighton BN1 9ET (www.creative-science.
org.uk/TV.html).
webwatch
Emma Woodley, RSC assistant education manager schools and colleges, takes a look at some websites of interest to students
Element games
http://education.jlab.org/
indexpages/elementgames.php
Learning the names of the
elements can be fun. On this
website there are matching
games, flash cards, hangman and
crossword puzzles. Settings allow
you to change the difficulty of
most of the games, and for some
you can also choose whether you
want to be tested on the first 20
elements, individual Groups, or
the whole Periodic Table.
You may copy this page for use within schools
Elementymology
http://www.vanderkrogt.net/
elements
This fantastic site contains a
wealth of information on the
origins of the elements in the
Periodic Table. A language key
lists the names of the elements in
72 different languages. There is
also a section on the history of
the use of symbols to represent
the elements, and the
subsequent development of the
modern Periodic Table. n
Go for gold!
Test yourself with questions from the
International Chemistry Olympiad
This question is adapted from Q3 of the 2004 UK Round 1 Chemistry
Olympiad paper.
Issue 109 march 2008
Looking for answers to chemically
related issues? Why not put them to
InfoChem’s professional chemists …
Q: When did oxygen become O2 (Stuart from Doncaster)
Professor Alan Dronsfield, University of Derby, says:
John Dalton introduced the notion of atoms of elements
having masses relative to the mass of a hydrogen atom in
1808. He used symbols for his elements such as a circle for
oxygen and a circle with a dot in it for hydrogen. Had he
written equations, he would have recorded the formation of
water from hydrogen and oxygen as:
•
+
=
•
In 1813 Jöns Jacob Berzelius proposed today’s chemical
shorthand, H for hydrogen, O for oxygen, Fe for iron etc. But
was oxygen O or O2? Evidence that it might be the latter was
provided by Gay Lussac in 1808. He found that (under similar
conditions of temperature and pressure) one volume of
nitrogen combined with one volume of oxygen to yield two
volumes of nitric oxide. Based on an equation similar to the
one above, we would have expected a 1:1:1 ratio.
This was resolved by Amedeo Avogadro in 1811, who
suggested that particles of gaseous elements might be split
into two when involved in a chemical reaction. Thus two half
molecules of nitrogen could combine with two half molecules
of oxygen to form two molecules of nitric oxide:
N2 + O2 = 2NO.
Avogadro’s ideas were largely ignored and much confusion
persisted as to what was a ‘correct’ formula for a molecule. In
1860, at Karlsruhe in Germany, a conference was called to
sort the matter out. Stanislao Cannizzaro circulated a
pamphlet he had written two years earlier, pointing out that
hydrogen and oxygen were diatomic molecules. Textbook
writer, Lothar Meyer recognised the sense in Cannizzaro’s
reasoning (which had Avogadro’s idea as its foundation) and
from then on there was little dispute.
Send your questions to:
The Editor, Education in Chemistry, the Royal Society of Chemistry,
Burlington House, Piccadilly, London W1J 0BA or e-mail: [email protected].
All questions published will receive a £10 HMV token.
A
quatic life can only survive because oxygen gas is
dissolved in the water; if the dissolved oxygen
concentration (DOC) in rivers and lakes falls below 5
mg dm–3 the water rapidly becomes toxic owing to decaying
organic matter, and most species of fish die. To measure the
DOC in river water, a sample is shaken with excess alkaline
Mn2+. In alkaline conditions Mn2+ is rapidly oxidised to Mn3+
by dissolved oxygen, producing a pale brown precipitate of
Mn(OH)3. The precipitate is reacted with an excess of
potassium iodide, which it oxidises to iodine. The iodine is
then determined by a titration with sodium thiosulfate
(Na2S2O3) solution of known concentration.
(a) Write balanced symbol equations for: (i) the oxidation
of Mn(OH)2 to Mn(OH)3 by aqueous oxygen; (ii) the
oxidation of KI by Mn(OH)3.
The equation for the titration reaction between sodium
thiosulfate and iodine is:
2Na2S2O3(aq) + I2(aq) → Na2S4O6(aq) + 2NaI(aq)
25.0 cm3 of a sample of river water treated in this way
required 25.0 cm3 of 0.00100 mol dm–3 sodium thiosulfate
solution.
(b) Calculate the concentration of the dissolved oxygen in
mg dm–3.
Nitrate(iii) ions (NO2–) interfere with this method because
they too can oxidise iodide ions to iodine. During the
reaction, NO gas is given off.
(c) Write a balanced equation for the oxidation of iodide
ions by nitrate(iii) ions, in aqueous acid.
To prevent the interference by nitrate(iii) ions, a solution of
sodium azide, NaN3, is added to the river water. During this
reaction, two gases are evolved: nitrogen and N2O.
(d) Write a balanced equation for the reaction between
nitrate(iii) ions and azide ions in aqueous acid.
WEB RESOURCES
To see the 2004 Olympiad paper (and answers!) go to:
www.chemsoc.org/olympiad
To find out more about how to take part in the RSC Olympiad
competitions for UK sixthform students go to:
www.rsc.org/olympiad
You may copy this page for use within schools
A day in the life of…
ACCOUNT EXECUTIVE:
Claire Long
Claire Long has spent the past 18 months working for
Santé Communications as an account executive. She
talks to Jonathan Edwards about her typical day.
Santé Communications is a healthcare communications
consultancy based in London. The company manages public
relations, medical education and healthcare communications for
large pharmaceutical companies such as GlaxoSmithKline and
Pfizer. Claire works in small teams (typically of six) on a variety of
projects, ranging from promoting clients’ products, through writing
and producing patient healthcare literature, to organising medical
teaching conferences. Claire is one of only 20 staff so she knows and
works with all the personnel at every level in the company.
Promoting products
Managing several projects, Claire shares time in a day among each
project. While working on a public relations project she spends much
of her day at her desk using web-based medical and pharmaceutical
literature to research and better understand a client’s product, eg a
drug, so that she can write an informative press release for the media.
To supplement her literature research Claire contacts senior doctors to
get an impartial comment on the product. Her public relations
projects can involve preparing press releases to promote a client’s
new product or producing information designed to limit damage to a
product’s reputation. For the latter Claire will spend time reviewing
the popular press, ie newspapers, magazines, websites etc, to gauge
the public image of the product, and that of competitors’ rival drugs.
Using information she has collected and the comments from senior
doctors, Claire writes a
pathway to success
�
�
�
2006 – present, account executive, Santé
Communications
2003–06, BSc biochemistry (1st),
University of Warwick
2001–03, chemistry, biology, maths and
English literature A-levels, Glenlola
Collegiate, Bangor
You may copy this page for use within schools
press release and
circulates it to journalists
and news agencies.
When journalists
enquire about the press
release, she must
respond by supplying more detailed information and by arranging
interviews for them with spokespeople for the client.
Claire also works on projects to produce literature aimed at patients,
which give advice on how to treat or deal with various illnesses, such
as schizophrenia or diabetes. To write material that’s useful, accessible
and sympathetic to the patient, Claire must research the medical
condition, its effect on the patient’s body, and also understand the
social implications of the illness, ie its impact on patients and their
families.
Claire Long
Managing events
Claire is also responsible for organising company events. Working
with her team she must book the event and the venue. Claire invites
attendees by e-mail or letter, and contacts speakers to talk at the
conference. She must brief the speakers on what they’ll be talking
about and, using PowerPoint, prepare their presentations. This
requires Claire to do in-depth research into the topic so that she can
talk in detail about the science with the presenting doctor – her
scientific background is essential here.
Her role as an events coordinator means that Claire doesn’t spend
every day in the office behind a desk. If she has arranged an
international conference, eg in Munich, Copenhagen, Athens or
Barcelona, Claire will travel to the event to make sure it runs
smoothly. This often means early mornings and late nights.
Work satisfaction
Claire enjoys the varied, busy nature of her work and being part of a
team. The two sides of the job complement her interests perfectly –
using her chemistry training to probe scientific research and
communicate her findings, and networking with clients and the
media. She gets great satisfaction and a real sense of achievement
from seeing her work published in print or discussed at a
conference. n
£50 of HMV tokens to be won!
FIND THE ELEMENT No. 2
Students are invited to solve Benchtalk’s Find the element puzzle,
contributed by Dr Simon Cotton of Uppingham School. Your task is
to complete the grid by identifying the 10 elements using the clues
below. Answers to all clues are metals.
Issue 109 march 2008
Prize wordsearch no. 38
Students are invited to find the 33 words/expressions associated with
genetically modified food hidden in this grid. Words read in any
direction, but are always in a straight line. Some letters may be used
more than once. When all the words are found, the unused letters, read
in order, will spell a further seven-letter word. Please send your answers
to the Editor at the usual address to arrive no later than Monday 7 April.
First correct answer out of the editor’s hat will receive a £20 HMV token.
ACROSS
1. Metal found in lime water. Forms an insoluble carbonate
but a slightly soluble hydroxide.
2. Radioactive metal used as a nuclear fuel.
3. Very precious metal.
4. Metal found in brass. Forms a white hydroxide that dissolves in
excess NaOH.
5. Another metal found in brass. Forms a blue sulfate and a blue
insoluble hydroxide that dissolves in excess ammonia solution.
6. Metal found in washing soda that gives a strong yellow
flame colour.
7. Metal used to coat steel cans.
8. Silvery metal that is used to plate the ‘brightwork’ of cars
and bikes.
9. Metal that gives a scarlet flame test.
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p
allergens
biodiversity
communication
concern
consumer
crops
disease resistance
dna
dna molecule
ecosystem
environment
fluorescent dyes
gene
genetic
gm evaluation
gm ingredients
health
humans
ingestion
insects
labelling scheme
pest
pesticides
plant
protein
real time pcr
sampling technique
sun
TaG
target analyte
toxins
traceability
virus
January PRIZE WORDSEARCH No. 37 winner
The winner was Andrew Fleming of Ibstock Place School, Roehampton, London
The 11-letter word was bloodstream.
1
10
2
3
4
5
6
7
7
If you have found the correct nine elements, in 10 down you will have
generated the name of a metal that burns strongly when heated. The
metal forms a soluble nitrate, chloride and sulfate but an insoluble
hydroxide and carbonate.
Please send you 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 April. First out of the editor’s hat
to have correctly completed the grid will receive a £30 HMV token.
1
10
a l u m
l e a
n e o n
h y d r o g
c a
b r o m i n
o x y g e
s
m e
2
i n i u m
d
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9
e
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b o n
l f u r
c u r y
Find the element no. 1
solutions and winner
The winner was Laura Marsden of
Hartlepool Sixth Form College,
Brinkburn, Hartlepool.
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