ISSUE MAY

STUDENT SUPPLEMENT MAY 2008 • VOLUME 45 • NUMBER 3

Cosmetics, naturallyChemicals from plant biomass

Alternative A-levelsCambridge Pre-U chemistry set to challenge students

Comparability studiesSTEM qualifi cations – harder than all the rest?

ISSN 0013-1350

Dissolving plasticsWhen the fashion designer met the chemist…

A day in the life of…David Henderson, accountant

On-screen chemistrySand dunes pose challenge for heroes

Plus…That’s chemistry!Organic prize quizWebwatchChemical Futoshiki

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: eic@rsc.org www.rsc.org/Education/EiC/index.asp

© The Royal Society of Chemistry, 2008Published in January and alternate months. ISSN: 1752-0533

IN THIS ISSUE

Editor Kathryn Roberts

Assistant editor James Berressem

Design and layout Dale Dawson

Fruit and vegetables are rich in antioxidants – chemicals thought to play an important role in protecting us from illnesses such as heart disease and certain cancers. Such chemicals react with free radicals in the body – for example hydroxyl radicals, which attack proteins, lipids and even DNA within our cells – rendering them harmless.

While people deliberate whether or not they believe this ‘antioxidant’ theory and the need to eat food rich in antioxidants, it seems our feathered friends don’t suff er the same misgivings. Fruit-eating birds – specifi cally the European blackcap, Sylvia atricapilla, known aff ectionately as the Northern Nightingale because of its tuneful chirp – go out of their way to select berries with the highest concentrations of fl avonoids. These polyphenolic compounds, which contain at least one phenol group (C6H5OH), are among the commonest antioxidants found in Nature.

In a study of blackcaps, Dr Carlo Catoni and his colleagues at the University of Freiburg and at the Vogelwarte Radolfzell Max Plank Institute for Ornithology in Germany fi rst established, by using HPLC (high-pressure liquid chromatography) and mass spectrometry, that two specifi c fl avonoids found in blackberry extracts are absorbed in the birds’

BIRD BRAINS KNOW BEST

blood. They then investigated whether the birds preferred food enriched with these fl avonoids, and fi nally if they gained any health benefi ts from ingesting fl avonoids.

According to the researchers, the blackcaps actively selected food with added fl avonoids, as evident by its darker colour.

Flavonoids such as anthocyanins are responsible for much of the dark colours found in blackberries, bilberries and elderberries. Previous studies by the researchers had shown that blackcaps do not show colour preference on nutritionally identical food.

By measuring the amounts of antibodies in the birds’ blood, the researchers found that those fed on a fl avonoid-rich diet produced

more antibodies than birds fed on a diet with no berry fl avonoids. These results, the researchers say, imply that fl avonoids can boost the immune system in a living organism. They hypothesise that their results may support other research that points to fl avonoids having benefi cial health eff ects on people.

Did you know?The bright red sap from Chinese plants such as Dracaena cochinchinensis is called ‘Dragon’s blood’. This mixture of sugars, salts and minerals has been used for thousands of years in traditional Chinese medicine mainly for treating wounds, stomach and circulatory problems. Recently, Chinese chemists identifi ed several fl avonoids (polyphenol compounds) in Dragon’s blood. In an article published in the Journal of Natural Products, the researchers explain that their results suggest that these newly identifi ed compounds show promise as antibacterial agents, and for treating stomach ulcers, cancer, thrombosis (blood clots) and stroke. It’s worth noting that ca 70 per cent of all new medicines discovered in the past 25 years have come from plants and natural products.

Download a pdf of this issue at: www.rsc.org/EiC 1

BRI

AN

GA

DSB

Y/SC

IEN

CE P

HO

TO L

IBRA

RY

Black caps favour fruity fl avonoids

InfoChem_May.indd 1 14/04/2008 11:29:56

2

C

W e live in a throwaway society. We use myriad materials every day in all sorts of ways, giving little

thought to where these materials came from or where they will end up. Plastics and increasingly cheap clothing, in particular, are

metaphors for waste. With landfi ll sites reaching crisis point and oil resources dwindling, few people would argue that we all need to become more responsible in the way we use and dispose of such materials. But how do we get people to think diff erently about materials, to think in terms of sustainability and recycling?

T A chance encounter between fashion icon Helen Storey and Tony Ryan, ICI professor of physical chemistry at Sheffi eld University, led to a solution that exploits the glamorous world of fashion with the equally creative world of chemistry.

Twenty years ago Helen Storey was designing clothes for Cher and Madonna, but is now more interested in fi nding solutions to problems such as plastics pollution and world water shortages. Recently she was working with a packaging company, trying to come up with some radical ideas for plastic packaging that would address plastics waste. ‘Why can’t a plastic bottle know when its contents have disappeared and signal the time for the bottle to disappear?’, she asked herself.

Later, listening to the radio 4 programme, Material World, she heard Tony Ryan talking about smart polymers, so she contacted him to fi nd out whether he could shed any light on the problem. He invited her to the department of chemistry at Sheffi eld and an alliance formed that, with funding from the Engineering and Physical Sciences Research Council’s (EPSRC) public engagement of science programme, has recently culminated in Wonderland. The exhibition of dissolvable textiles has an underlying message on sustainable materials, and has seen the chemist and the fashion designer go on to develop a water purifi cation system for people in the developing world.

� is year saw the launch of a fashion show with a diff erence. Wonderland, which opened at the London School of Fashion in January for two weeks, exhibited beautiful dresses that disappeared in a giant bowl of water before the public’s eyes, setting off underwater fi reworks as they dissolved. Does such imagery merely refl ect a division between the worlds of art and science, or is there another more poignant message?

Plastics – going out of fashion

ISSUE MAY

BA

RRY

EVA

NS/

UN

IVER

SITY

OF

SHEF

FIEL

D

You may copy this issue for use within schools

InfoChem_May.indd 2 14/04/2008 11:30:25

Plastics at an exhibition…

Ryan told Infochem, ‘We are both keen to get people to think about the way they use materials and to use them more responsibly. But rather than preach about it, we realised we could reach a wider group of people by using fashion and glamour’.

B Ryan knew of a polymer that was dry to touch, making it suitable to work up into dresses, and would dissolve in water. ‘Helen would be able to make beautiful gowns in which we could embed all sorts of chemistry, and they would obey the second law of thermodynamics and dissolve’. This polymer, he explained, is used to form the clear pouches that hold laundry and dishwashing liquids, and dissolves in water. Detergents comprise salts which are attracted to water more than the polymer is – the water in the liquid detergent is bound so strongly by the salt ions that only when the polymer is in large amounts of water, as is the case in a washing machine or dishwasher, will it dissolve.

The polymer is polyvinyl alcohol (PVA), but because the monomer, vinyl alcohol (ethenol, CH2=CH(OH)), doesn’t exist on its own (it coexists in equilibrium with its isomeric ketone, CH3CHO), PVA is made by polymerising vinyl acetate (ethenyl ethanoate), followed by a saponifi cation reaction. The latter step cleaves the ester, via hydrolysis, to form the alcohol. The result is a copolymer of vinyl alcohol and vinyl acetate, the relative amounts of which can be varied by controlling the saponifi cation reaction. The more acetate, the less soluble in water is the copolymer; the more alcohol, the more soluble in water is the copolymer. The temperature at which the copolymer dissolves can thus be controlled by changing the relative amounts of acetate and alcohol.

So the polymer, explained Ryan, could be used to make a bottle that when empty could be fi lled with boiling water, which would dissolve the polymer and on cooling would

C

designers with ‘underwater fi reworks’, which could be incorporated in the buttons. Small pouches, made of the same copolymer are fi lled with equal amounts of bicarbonate of soda (sodium hydrogen carbonate) and sodium citrate (the sodium salt of citric acid, 2-hydroxypropane-1,2,3-tricarboxylic acid), and a solid dye. As water leaks into the pouch, the bicarbonate of soda and sodium citrate react, producing carbon dioxide gas, which fi res the dye into solution, producing coloured streamers in the water as it sinks. A giant magnifying glass bowl to hold the water adds to the eff ect. Ryan comments, ‘People will ask, “why are you destroying those beautiful gowns?” and we will say: “to make you think about how you are slowly destroying the planet by throwing away materials”. And because we want them to think in new ways about materials, plants are seen growing from the gooey gel that the dresses have changed into’.

Storey designed the dresses and her team made up the garments using lasers to cut the ‘fabric’ and specially designed heat sealers – essentially a wheel on the end of a soldering iron – to bond seams together. Intricate patterns, similar in appearance to lace, could be cut out using the lasers.

T -Tony Ryan is well known in the chemistry community for his work on polymers. The focus of his recent research has been in the development of nanoscale (10–9 m), synthetic muscle, which has the potential to be used as molecular motors for the electronics industry, in robotics for example. For this he uses a polymer with ionic side groups, the ionic

form a gel if a crosslinking molecule, such as borax (disodium tetraborate(III)-10-water), was added. If the cap of the bottle were designed like a pepper pot and contained fl owering or herb seeds and rooting compound, then where once you had a plastic bottle which you would have thrown away, you could have fl owers or herbs growing instead.

To add to the artistic eff ect of the dissolving dresses at the exhibition, Ryan provided the

ALE

X M

AG

UIR

E

3You may copy this issue for use within schools

designers with ‘underwater fi reworks’, which

D� igner plastics…

InfoChem_May.indd 3 14/04/2008 11:31:03

4

nature of which can be switched ‘on’ or ‘off ’ by changing the pH of its environment.

In its ionic state, at pH 4–6 (in a weak acid), the polymer attracts water and swells up, and in its non-ionic state (at low pH) the polymer loses water and collapses. ‘By separating the weakly and strongly acidic solutions with a membrane (thus creating an osmotic pressure between the two solutions) we can change the pH of the environment of the polymer’, explains Ryan, ‘and get the synthetic muscle to change shape and thus do work’.

While talking to the artists about his work, Ryan tells them how, in a similar system, the osmotic pressure between two liquids can be exploited to provide clean drinking water for soldiers in Iraq and Afghanistan. ‘The soldiers have a bag made of regenerated cellulose (the

membrane) containing salts and sugar’, he says. ‘When they come across a stream or a pool of dirty water, the soldiers fi ll up their bags, and the osmotic pressure created by the salt/sugar solution pulls clean water through the membrane. Intrigued, the artists ask, ‘could you use the same materials that you use for your synthetic muscles in a water purifi cation system?.’

In collaboration with the artists, Ryan and his team at Sheffi eld have developed a water purifi cation ‘pillow’ based on ‘synthetic muscle’, that could be used by the military and people in developing countries. In dirty, contaminated water, the polymer electrolyte absorbs pure water across a membrane and swells up. To release the water, simply apply a pressure that is bigger than the osmotic

pressure and the water comes out – take the membrane away and squeeze the gel. The portable system has been awarded a patent and Ryan is currently seeking venture capital to develop the prototype for the market.

The Wonderland exhibition will be in Sheffi eld in a city-wide event at Meadowhall, the University of Sheffi eld, the Botanical Gardens, and the Millennium Galleries between 18 June and 13 July; and in Belfast at the Ormeau Baths Gallery, 7 October to 9 November.Kathryn Roberts

Seams ea� …

“… … .”ISSUE MAY

ALE

X M

AG

UIR

E

Why do you say that?We eat, smell and taste molecules.

Don’t we eat food to give us energy?That is an important function of food, but it also supplies protein to provide us with amino acids. Our bodies use these to make other proteins.

What are amino acids and proteins?Most amino acids, such as alanine (1), contain just carbon, hydrogen, oxygen and nitrogen atoms. They have an amine (–NH2) and a carboxylic acid (–CO2H) group, hence the name amino acid. An amino acid can join – at either end – with another amino acid to form a dipeptide (2), linked by a peptide bond. This bond is formed by a condensation reaction involving the removal of a H2O molecule. Because amino acids can react at either end, they can form long chain molecules. A molecule with

lots of peptide bonds is called a polypeptide. If the molecular weight of a polypeptide is more than 6000, it is known as a protein. There are 20 diff erent amino acids that are used in diff erent combinations to make the proteins in our bodies. The body is unable to make 10 of these amino acids, which means we have to get them through our diet.

What happens to protein we eat?Our bodies take in food proteins, break them down into their amino acid constituents and then reassemble them in diff erent sequences and combinations to make diff erent proteins.

Why does food have a taste and smell?Life would be boring otherwise. Food is more attractive because of molecules which impart fl avour and odour. These traits also give us clues about what we are eating, eg heptan-2-one (3) is

a characteristic fl avour compound of blue cheese. When food goes bad, proteins break down into smaller molecules with higher vapour pressures, which we detect as a smell. These act as a warning. For example, when fi sh protein is attacked by enzymes and bacteria the noxious chemical trimethylamine (4) is formed which we recognise as the odour of rotting fi sh. ■

Simon Cotton, chemistry teacher at Uppingham School, looks at the molecules in our lives. In this issue: Food is chemistry

that’s chemistry!

You may copy this issue for use within schools

(1) Alanine

C C

H O

OH

CH3

H2N

(2) Dipeptide

C C

H O

N

CH3

H2N C

H H

CH3

C

O

OH

Peptide bond

H3C CH3

O

(3) Heptan-2-one

NH3C CH3

CH3

(4) Trimethylamine

InfoChem_May.indd 4 14/04/2008 11:31:27

5

Ice cold in Alex is a classic black and white fi lm starring Sylvia Syms, John Mills and Anthony Quayle. In 1942 in the Libyan war zone, the three fi nd themselves crossing a mined desert in an army ambulance trying to get back to the safety of Alexandria. Nearing the end of their journey they are forced to attempt to drive up a massive sand dune to escape the desert. Realising that the engine will simply burn out in the intense heat, they do a clever thing. They remove the spark plugs from the engine so that the pistons no longer limit the motion of the engine, put the engine in lowest gear and use the crank handle to crank the ambulance up the dune. After several tries they succeed, allowing them to drive back to Alex. There is a classic scene towards the end of the fi lm where they toast their safe arrival, downing several glasses of beer – hence ‘Ice cold in Alex’! But can it be done?

In our Hollywood science TV series Robert Llewellyn and I cranked a car up a steep hill to test this stunt. The ambulance would have

been much heavier but it would have had a greater gear ratio and so we felt confi dent that they could have done it – providing the slope of the dune was not too great.

So how steep is a sand dune? You might think that a sand dune could be any steepness, from almost fl at to a vertical cliff but this is not so. It’s true that sandstone or chalk can produce near vertical cliff s as you can see in quarries or on the south coast such as Beachy Head and the White cliff s of Dover. But this is because they are solid; sand is more fl uid.

An experimentTry this experiment. Take a salt cellar and pour salt onto a fl at table top. A little mound of salt will build-up and it looks like it will grow ever steeper to make a pile. All of a sudden you notice that the grains slip and the pile loses height to form a mound with a larger area base. As you continue to add more salt the mound grows higher and steeper but at a maximum angle we see our ‘salt dune’ slips.

What is true of our salt crystal model is also

true for many diff erent types of small particles, including sand. Our model gives us some insight into the maximum steepness of a sand dune – about 30–40 degrees.

Since we know that there is a maximum angle beyond which the grains can’t go it means we can be much more confi dent that our heroes could have cranked the ambulance up the sand dune. It would have been a lot of hard work though!

(If you want to fi nd out more about the science of fl owing particles go to http://www.seed.slb.com/en/scictr/lab/heleshaw/index.htm.)

Dr Jonathan Hare, The CSC, Chemistry Department, University of Sussex, Brighton BN1 9ET (www.creative-science.org.uk/TV.html).

Jonathan Hare asks…SAND DUNES: can you crank an ambulance up a sand dune?

Earth – our world in motionhttp://www.amnh.org/ology/earth/This website, from the American Museum of Natural History, is packed with fascinating facts about

the structure of the Earth, covering rocks, volcanoes, earthquakes, and plate tectonics. It has good animations and illustrations, and is interactive. There are also interviews with Earth scientists and many experiments for you to try at home.

Plate tectonicshttp://www.ucmp.berkeley.edu/geology/tectonics.htlmThis website describes how the theories of the development of the Earth evolved – its mountain ranges, the causes of volcanoes and

earthquakes. The mechanisms that cause the plates of the crust to move are described in detail, and there are clear animations showing you how we believe the surface of the Earth has changed over the past 750 million years.

Emma Woodley, RSC assistant education manager, takes a look at some websites of interest to students

webwatch

ASS

OCI

ATED

BRI

TISH

/TH

E KO

BA

L CO

LLEC

TIO

N

Bright spark has the answer

You may copy this issue for use within schools

InfoChem_May.indd 5 14/04/2008 11:31:50

H3C CH2

CH3

H3C CH3

CH3

H3CCH2 H3C

CH3H3C CH2

CH3

CH3

H3CCH2 H2C CH2

CH2

CH3 H3CCH3

H3C

CH3

H3CCH3

CH3

(a) (b) (c)

(d) (e) (f)

(g) (h) (i)

(j)

(k) (l)

(m) (n)(o)

(p) (q)

Use the letters a–q to answer the questions (apart from question 1).

1. Name each compound. Which compound(s) are: 2. Alkanes? 3. Alkenes? 4. Arenes? 5. Cyclic hydrocarbons? Which compound(s): 6. Decolourise bromine water in the dark? 7. Only react with Cl2 in the dark in the presence of

a Lewis acid such as AlCl3? 8. Undergo addition with HBr? 9. Can be oxidised to benzoic acid on boiling

with KMnO4 solution? 10. Undergo side chain substitution with Cl2

in the presence of uv light? 11. Do not occur in Nature but are made by cracking? 12. Can be catalytically hydrated to make alcohols? 13. Undergo electrophilic substitution to make

a nitro compound? 14. Are three isomers? 15. Are two more pairs of isomers? 16. Add HCl to form a tertiary halide? 17. Add HCl to form a secondary halide? 18. Add HCl to form a primary halide? 19. Exist as geometric isomers? 20. Have a chiral carbon? 21. Result from an elimination reaction of

2-chlorobutane? 22. Can be made by an isomerisation reaction of E? 23. Could be made industrially by reforming

reactions of O? 24. Are planar? 25. Can be polymerised to make polystyrene? 26. Are used to make ethylbenzene

industrially? 27. Only have bond angles at carbon ca 109½°? 28. Only have bond angles at carbon ca 120°? 29. Have bond angles at carbon both ca 109½°

and ca 120°?

If you are studying AS/A2 chemistry, have a go at Infochem’s latest quiz and maybe your revision might pay for some new DVDs, CDs, books or computer games. The questions, contributed by chemistry teacher Simon Cotton of Uppingham School, are based on organic chemistry covered in the current A-level speci� cations.

6

SEND YOU ANSWERS TO: The Editor, Education in Chemistry, the Royal Society of

Chemistry, Burlington House, Piccadilly, London W1J 0BA (e-

mail: eic@rsc.org), to arrive no later than Friday 6 June.

First entry out of the editor’s hat with correct answers

to all 29 questions will receive a £50 HMV token.

ISSUE MAY

latest quiz and maybe your revision might pay for some £50 OF HMV TOKENS TO BE WON!

If you are studying AS/A2 chemistry, have a go at Infochem’s latest quiz and maybe your revision might pay for some latest quiz and maybe your revision might pay for some £50 OF HMV TOKENS TO BE WON!£50 OF HMV TOKENS TO BE WON!£50 OF HMV TOKENS TO BE WON!ORGANIC PRIZE QUIZ

You may copy this issue for use within schools

InfoChem_May.indd 6 14/04/2008 11:32:14

H3C CH2

CH3

H3C CH3

CH3

H3CCH2 H3C

CH3H3C CH2

CH3

CH3

H3CCH2 H2C CH2

CH2

CH3 H3CCH3

H3C

CH3

H3CCH3

CH3

(a) (b) (c)

(d) (e) (f)

(g) (h) (i)

(j)

(k) (l)

(m) (n)(o)

(p) (q)

7

ACCOUNTANT:David Henderson

A …

David is in the fi nal year of a three-year contract with BDO Stoy Hayward to qualify as an accountant. He talks to James Berressem about his typical day.

BDO Stoy Hayward is the UK member fi rm of accountancy network BDO International. Based in London, David joined the fi rm on its graduate training programme (GTP) in 2005 along with some 40 other graduates. He is currently a senior on the GTP, studying towards an ACA accountancy qualifi cation and works in the audit and business assurance department. As part of his contract, David shares his time between work and periods of up to three weeks’ paid study/exam leave at a fi nancial training college. At the end of this year, after 450 days’ work experience and, importantly, nine exams passed, he will qualify as a chartered accountant.

A Audit and assurance services off ered by accountancy fi rms provide an independent opinion on information published by client companies. A fi nancial audit aims to ensure that the fi nancial statements released by a company are accurate, prepared correctly, and provide a fair representation of the organisation’s position and performance to interested parties, eg shareholders.

David specialises in audits for businesses in the property and professional services sectors – his clients range from large, listed property companies with over £2 billion assets to growing architect fi rms with turnovers of £1–6 million. Each audit lasts on average

three weeks and involves obtaining an in-depth under-standing of the client’s operations, the industry in which the company operates and the commercial and fi nancial issues it faces.

For most of the project David spends each day visiting the client’s premises with his audit team, which comprises a junior and a semi-senior (roles he has progressed through while on the GTP). The team collect evidence to support their assessment of the company’s fi nancial statements. As the senior on the audit team David meets with the client’s managing or fi nancial directors – his experience in industry has helped prepare him for dealing with such high-level staff .

David is responsible for organising and monitoring the audit team’s work. He delegates many of the repetitive tasks involved in auditing, such as checking invoices and bank statements, to his junior while his semi-senior colleague might work on the audit of stock/work in progress, which can be governed by complex accounting standards. This frees up his time to discuss with the client the business strategy and advise on how to manage potential risks. However, on the rare occasion, some jobs can involve completing the accounts for the clients, which requires David to use accounting skills such as double entry book-keeping.

Back at BDO’s offi ce David fi nalises the audit fi le, chasing up the client for outstanding documents and explanations. When all the required evidence has been analysed and signed off , David compiles a report detailing the fi ndings of the audit. A BDO partner reviews this at a fi nal meeting with the client’s managing director to discuss any issues prior to signing off the accounts.

Q Although the pressure to pass exams makes this qualifying period stressful, David enjoys the varied nature of his work and the challenges this brings – he is constantly working with new people in diff erent environments during audits. The ACA qualifi cation will give him a good grounding in business knowledge, which David hopes will unlock many new career opportunities. ■

PATHWAY TO SUCCESS

2005–pr� ent, qualifying accountant, BDO St� Hayward, London

2004–05, analytical r� earcher, Health and Beauty Care R&D, Pro er & Gamble, Egham2000–04, BSc chemist ry with year in industry (2.i), University � N� ingham

1998–2000, chemist ry, physics and maths A-levels, Lymm High School, Cheshire

●

●

●

●

David Henderson

£50 OF HMV TOKENS TO BE WON!

You may copy this issue for use within schools

InfoChem_May.indd 7 14/04/2008 11:32:43

ISSUE MAY

£50 OF HMV TOKENS TO BE WON!£50 OF HMV TOKENS TO BE WON!

March PRIZE WORDSEARCH No. 38 winnerThe winner was Paige Johnson of Biddulph High School, Biddulph, Stoke-on-Trent The seven-letter word was DEGRADE.

Find the element no. 2 solutions and winnerThe winner was Fatima Khalil of Claremont High School, Harrow.

1 10

2

3

4

5

6

7 7

8

9

c a l c i u m u r a n i u m g o l d z i n c c o p p e r s o d i u m t i n c h r o m i u m l i t h i u m

FUTOSHIKI CHEMICAL ELEMENTS No. 1Contributed by education consultant John Payne, this is Benchtalk’s chemical take on the Japanese number puzzle Futoshiki. Students are invited to solve the puzzle by completing the grid using the symbols of the Group 18 elements helium, neon, argon, krypton and xenon.

The objective is the same as for numbers in Futoshiki: each of the fi ve elements must appear only once in each row and each column. The ‘greater than’ or ‘less than’ signs between some of the squares indicate where an element must have an atomic number larger or smaller than its neighbour.

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 Friday 6 June. First out of the editor’s hat to have correctly completed the grid will receive a £30 HMV token.

8

Students are invited to fi nd the 34 words/expressions associated with spices 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 fi ve-letter word. Please send your answers to the Editor at the usual address to arrive no later than Friday 6 June. First correct answer out of the editor’s hat will receive a £20 HMV token.

PRIZE WORDSEARCH No. 39

ALKYLAMIDE FAMILY

ALDEHYDESAROMABAY LEAVESBLACK PEPPERSBUDS OF CLOVESCELLCHILLI PEPPERSCINNAMALDEHYDE

CINNAMONCLOVESCOOKCORIANDERCROCETINDIETEATENZYMESGINGERGINGEROL

HOTHYDROCARBON CHAIN

INDIAN LONG PEPPERS

NUTMEGPELLITORINEPICROCROCINPIPERINEPIPERLONGUMINE

SAFRANALSAFFRONSEED SPICESTHERMAL STIMULUS

TURMERICZEAXANTHIN

A T H E R M A L S T I M U L U S I

L C P S E V O L C F O S D U B N N

K I I T U R M E R I C O O K D S I

Y N P E C O R I A N D E R I E C A

L N E N I R E G N I G C A V E H H

A A R I N S A F F R O N O L G I C

M M L R N P R H O T L L L U I L N

I A O O A I O C R O C E T I N L O

D L N T M C M E N Z Y M E S G I B

E D G I O E A G E M T U N R E P R

F E U L N S P I P E R I N E R E A

A H M L Z E A X A N T H I N O P C

M Y I E P B A Y L E A V E S L P O

I D N P S A F R A N A L E A T E R

L E E E R S E D Y H E D L A E R D

Y R E N I C O R C O R C I P I S Y

S D B L A C K P E P P E R S D Y H

Kr Xe

Ar

Download a pdf of this issue at: www.rsc.org/EiC

InfoChem_May.indd 8 14/04/2008 13:08:55