The Mole January 2015

TheMoleIn this issue

... FOR ANYONE INSPIRED TO DIG DEEPER INTO CHEMISTRY

Registered Charity Number 207890

Imidacloprid The pesticide that might be buzzing away our bees

Avogadro's lab

Crystals, light and optical illusions in the sky

Chemistry is like... The Simpsons

What can the cartoon family tell us about chemistry?

DNA barcodes Tracking your food

PlusAdvice from Dr Careers and Dr ChemNet

ISSUE 01 | JANUARY 2015

Advances in science have improved lives in many ways. Medicines have increased life expectancy, we have been blessed with computers and televisions, and flight has opened up the world fortravel.

Cosmetics, the science of looking good, is no exception. In ancient times, women applied crushed bugs directly to their skin. Nowadays, there is a huge array of products that variously promise to abolish wrinkles, destroy dandruff and restore vibrancy to worn outhair.

Nail varnish has evolved, too. Good old nail polish, which chips easily and has to be constantly reapplied, has been superseded by durable varnishes such as Shellac, which can endure two weeks of hard knocks before they look worn. But just how do thesework?

The two styles of varnish are very different. Classic nail polish is essentially the same as paint. The three main

things needed to make it work are a pigment, which provides the colour, an adhesive, which sticks the pigment to whatever you are painting and a solvent, which keeps the paint in a liquid form until it has been applied to the surface, where it can dry out and solidify into a permanent finish. This is different from Shellac, which is an example of a light-cured gel varnish. This means that ultraviolet (UV) light is used to create a polymer on thefingernail.

Coating and curingLets start with what happens when you put on gel varnish nails. The first step is to prepare the fingernails so that they are ready to be coated. This means they should be cleaned, disinfected andbuffed.

Next the base coat is applied. This is painted on using a brush, just like normal nail polish. What happens next is the different part. The beauty technician will place the

TomHusband explains how varnishing your nails is more like making plastic thanpainting

Polished polymers

EditorKaren J Ogilvie

Deputy editorPaul MacLellan

Assistant editorDavid Sait

ChemNet contentFrancine Atkinson

Production Dale Dawson, Scott Ollington, Emma Sargent and Lizzy Brown

PublisherAdam Brownsell

The Mole is published six times a year by the Royal Society of Chemistry, Thomas Graham House, Cambridge, CB4 0WF.01223 420066; [email protected] www.rsc.org/TheMole

The Royal Society of Chemistry, 2015. ISSN: 2049-2634Copying is permitted within schools and colleges.

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Avogadro's

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Chemistry

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The monomers used in Shellac nails are methacrylates. The word acrylate describes many kinds of compounds, all of which derive from propenoic acid (commonly called acrylic acid. Methacrylates are acrylates with a methyl group on the second carbon atom. Further modifications can then produce derivatives like tetrahydrofurfuryl methacrylate and hydroxypropyl methacrylate (HPMA), both of which are ingredients inShellac.

Acrylic acid

General formula for methacrylateHydroxypropyl methacrylate (HPMA)

Methacrylic acid Tetrahydrofurfuryl methacrylate

Another chemical ingredient in Shellac is (1-hydroxycyclohexyl)(phenyl)methanone, which acts as a photoinitiator. Photoinitiators are chemicals that readily absorb UV light to become radicals. A carboncarbon bond is broken by the light and then each unpaired electron will pair up with a new electron.

Most of the time this new electron will be taken from the double bond in a methacrylate monomer molecule. One of the two doubly bonded carbons will form a new bond with the photoinitiator fragment, while the other carbon will be left with an unpaired electron. This radical may then attack another methacrylate monomer

nails under a UV lamp to cure the base coat, meaning that it turns from a liquid to asolid.

Now the main coat is applied. This will give the varnish its final colour. Just like the base coat, this is painted onto the nail and then cured under the UV lamp. The main coat is not applied all in one go, but in a series of thin layers, each of which has to be separately cured under the UVlamp.

After several applications of the main coat, a top coat is applied, which is usually the same substance as the base coat. A final exposure under the lamp completes the curing process. At this stage, the nails are wiped with a solvent, such as acetone, to remove any tacky residue. Finally, after being filed and dusted off, the nails areready.

Starting a chainreactionPlacing the nails under the UV lamp is a vital stage of the process. The UV radiation triggers a chemical reaction that causes a large number of small molecules, which we call monomers, to join together into long chains called polymers. You can think of the monomers as beads being strung together into a long necklace, which represents the polymer. In the case of nail varnish, this is an example of radical addition polymerisation the ultraviolet light creates radicals that join the monomerstogether.

Radicals are highly reactive chemical species with unpaired electrons. When a chemical bond absorbs UV radiation of the correct wavelength, a bond can undergo homolytic fission, meaning that the bonding pair of electrons is separated with one electron going to each of the bonded atoms. An unpaired electron will rapidly pair up with another electron, which is often snatched from another bond. This means that two more electrons are separated, one of which makes a bond with the first radical, and the second of which remains unpaired, creating a new radical. This is a great example of a chainreaction.

UV lamp cures Shellac nail varnish

The word shellac comes from the lac insect from south-east Asia. The first version of the varnish was made with a resin gathered from the femaleinsect.

According to the Online Etymology Dictionary, the word used to have two slang meanings. In the 1920s, to be shellacked meant either to be soundly beaten or to be blinddrunk!

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www.rsc.org/TheMole January 2015 | The Mole | 3

contain some kind of methacrylate. This means that all of the monomers and oligomers can join together by the same radical addition reaction that we saw for the methacrylatemonomers.

When the mixture is exposed to UV light, all of the different pieces link together. The longer oligomers will join up to make long chains, while the monomers create cross links that bind the chains together into a huge, interconnected network ofchains.

This cross-linking makes Shellac an example of a thermoset plastic, meaning that it cant be melted or dissolved. However, these polymers can absorb solvents, such as acetone, which can transform them back into a gel. This is how gel varnish isremoved.

Striking the balanceThere are two benefits to using this blend of monomers and oligomers. Firstly, it makes the reaction go faster. The longer the oligomer, the harder it is to turn it into a radical and react it with a neighbour. On the other hand, if the mixture was composed solely of monomers, more chemical bonds would have to be made. So if the varnish consisted solely of monomers, or oligomers, the gel would need to be cured for longer under the UV lamp. Also, oligomers are more viscous than monomers, meaning they flow more slowly. A varnish consisting only of monomers would be so runny that it would spill off the nail onto the surrounding skin, which we really dont want these compounds irritate the skin.

So why is the varnish applied in layers? UV radiation cannot penetrate very far into the gel, so it must be brushed on in thin layers to ensure that the mixture is completelypolymerised.

The ingredients we have seen are those involved in polymerisation but many more are added. There are emulsifiers that keep all the other ingredients in solution, cellulose acetate butyrate is used because its UV resistance maintains the nails glossy appearance, dyes provide colour and plasticisers keep the varnish flexible so it does notsnap.

As we have seen, the chemistry of Shellac varnish is very complex. Luckily, the complicated science is carried out in the lab, making life simple at the salon. Building on a long tradition of polymer research, cosmetic scientists have found another way to make life easier, with nails that keep their glossy appearance forlonger.

with the chain reaction repeating until a long polymer chain has beencreated.

Radical chain reactions are ended when two separate radicals collide. In this case, termination could occur when two growing chains of monomerscollide.

While this is a feasible mechanism for the polymerisation of a methacrylate, it is not a very accurate description of what happens when Shellac is applied. The methacrylates listed in the ingredients do polymerise, but not just with each other. In fact, they form a huge, criss-crossing network of polymer chains with another variety of compounds calledurethanes.

The chemical networkThere are two examples of urethanes in Shellac varnish. They are di-HEMA trimethylhexyl dicarbamate and bis-HEMA poly(1,4-butanediol)-22/IPDI copolymer. Notice that both names contain HEMA, which stands for hydroxyethyl methacrylate another methacrylate. Also notice the word copolymer in the second ingredient this is a polymer composed of two or more different monomers. The two polymers used in urethanes are alcohols, such as HEMA, and carbamates. These urethane ingredients can also be referred to as oligomers; they consist of three or four monomers that have already been joinedtogether.

Lets review the situation. Shellac varnish is a concoction of monomers and oligomers of varying length. The gel is essentially a mixture of polymers at different stages of development, rather like a forest in which young saplings grow alongside giant redwoods. If all of these trees were cut down, they could be used to make wooden beams of different lengths. These in turn could be assembled into a house, with the shorter beams being used to make window frames, medium-length beams to make doorways and the longest beams to make the frame of the house. Similarly, the Shellac ingredients join into one giantstructure.

In spite of their many differences, what all of these varnish ingredients have in common is that they each

Did you know?

Although gel-cured nail varnishes are great for keeping nails pretty, it's important to consider their impact on health. Acetone, used in application and removal of Shellac, and UV light are both harmful to skin. Because of this, in 2013, dermatologist Chris Adigun warned against applying Shellac too often.

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Monomers

Oligomers

Under UV light oligomers join into long chains and monomers provide cross links and make a network.

The monomers and urethane oligomersin Shellac varnish



Magnificent molecules

New pesticides based on spider venom are harmless to bees and could replace neonicotinoids: http://rsc.li/1ooOPtB

Agrochemical companies have therefore made

modified versions of nicotine that selectively affect

insects and are less toxic to mammals. The first of

these neonicotinoid insecticides, developed by Bayer

CropScience in the early 1990s, was imidacloprid,

which quickly became the most widely used

insecticide in theworld.

Imidacloprid is highly toxic to bees, both by contact

and ingestion. It is also a systemic insecticide, which

means it penetrates into the plant and circulates to all

parts, including pollen and nectar. This means that,

to protect bees from exposure, imidacloprid needs to

be applied to crops very carefully, so that any residue

that does end up in the pollen and nectar is below the

level that is harmful to bees, while still maintaining

sufficiently high concentrations in leaves and sap to kill

caterpillars and aphids, forexample.

Uncertain safetyBut exactly what level of residue is safe is a matter

of debate. From its own trials, Bayer CropScience

says that when imidacloprid is applied correctly, the

residue in pollen and nectar is usually below 5 parts

per billion well below what the company claims is

the safe level of 20 parts per billion. But independent

studies have found widely varying residue levels, with

some exceeding the 20 parts per billionthreshold.

In the face of conflicting evidence, in April 2013 the

European commission called a 2-year temporary halt

to the use of three neonicotinoids imidacloprid,

clothianidin and thiamethoxam on crops that attract

bees. In the meantime, farmers may end up resorting

to older, less effective pesticides, which could result in

more spraying, and have an even worse impact on the

bees, as well as other field dwellinganimals.

Either way, the saviour of the bees will be science.

Lets just hope it can be sorted out before it becomes

too late, both for the bees and the food that they

allow us toproduce.

Pesticides are an integral part of modern agriculture. Using chemicals to protect crops from weed competition, fungal infection and insect pests, combined with synthetic fertilisers from the HaberBosch process, led to the green revolution of the mid-20th century. Crop yields increased significantly, supporting growing populations with the same amount of land, and saving millions fromstarvation.

But pesticides are also controversial. By their nature, they are toxic to their target organisms, but they also need to be selective for that target. Ideally, they should cause no harm to the crop they are protecting and any other plants or animals they happen to come in contact with. All sorts of animals like mice, voles, frogs and earthworms can be at risk. But arguably, the most difficult animals to protect arebees.

Mysterious deathsHoneybees, bumblebees and various kinds of solitary wild bees are important pollinators for crops, especially fruit, nuts and vegetables. As a rough estimate, about a third of all the food we eat comes from bee-pollinated crops. And the bees aredying.

In recent years, beekeepers and entomologists have become increasingly worried about colony collapse disorder an alarming problem where hives of bees suddenly and mysteriously die out. Various factors are suspected to contribute to colony collapse, and high on the list is the use of pesticides. In the last few years, attention has focused on one particular class of insecticides theneonicotinoids.

A blessing and a curseNeonicotinoids, as the name suggests, are based on nicotine. The nicotine in plants like tobacco is a natural deterrent to caterpillars and other insects that might try to eat the plant. It works by binding to receptors in nerve cells that usually respond to the neurotransmitter acetylcholine. This disrupts signals in the nervous system, causing paralysis anddeath.

But nicotine itself is not very selective it is toxic to mammals and other animals as well as insects.

Phillip Broadwith explores a controversial compound that could be buzzing away our bees

Imidacloprid

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Imidacloprid is a controversial pesticide that might be harming bees

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January 2015 | The Mole | 5

Avogadro's lab

Parhelia are often accompanied by a halo of light around the sun

Sometimes they can be seen as part of a halo around thesun.

A famous example of the appearance of a parhelion was during the wars of the roses. Three suns were seen to be rising at dawn prior to Edward IVs victory at the battle of Mortimers Cross. This good omen led him to adopt the symbol of parhelia as his badge it can still be seen pictured on the sign of the Mortimers CrossInn.

Find out moreOur activity in this edition is to learn more about the effects of ice crystals in the atmosphere. The links below are a great place to start. The most commonly observed effects are parhelia but you might be able to find some examples of light pillars and sun haloes.

Ice crystal haloes http://bit.ly/1dOToh1

Sun dogs http://bit.ly/162XYGA

Sun dogs, mock suns or parhelia http://bit.ly/12DYGrK

The 22 halo http://bit.ly/12DYLf5

Most of the forms of ice that youre familiar with such as ice cubes, icicles or hailstones dont look very crystalline. These forms of solid water are in fact very ordered at the molecular level, but the way they form with lots of crystals building up at the same time can result in quite a lumpy and amorphousappearance.

Ice in the skyHowever, if ice crystallises slowly, a single crystal can form. Crystals like this are often produced in the atmosphere but can have many different shapes. Some make columns, some make plates and others form the familiar snowflake. What all of these have in common is that their shapes are based on hexagons. As a result, they have the same angles between their crystal faces and so they affect light in regular and predictableways.

Snowflakes, however, are a little different. Snowflakes form from microscopic water droplets. While these droplets are freezing, tiny variations in the temperature and humidity will cause different parts of the crystal to grow at different rates. The simple hexagon shape of the crystal therefore becomes decorated with patterned arms ofice.

Snowflakes have such intricate patterns and tiny crystal faces that all the light that falls on them is reflected, which is why snow is white instead of colourless like an icecube.

On the other hand, ice crystals that form hexagonal plates and columns are like jewels or prisms that light can travel through. These prisms can refract light so its path is changed and colours can be separated. Crystals that form hexagonal plates fall through the sky like leaves the plate is mostlyhorizontal.

Optical illusionsIt is ice crystals like these that cause interesting visual effects when they interact with light from the sun. Light pillars, sun haloes and even false suns can sometimes be observed on cold, cloudlessdays.

The most well-known of these effects are parhelia (also known as sun dogs, or false suns). A parhelion appears when plate-like ice crystals fall horizontally. Sunlight passing through the crystal is diffracted at an angle so that an observer will see two false suns either side of the real sun.

StephenAshworth explains how ice crystals can create optical illusions in thesky

Crystals and light

www.rsc.org/TheMole

SafetyTake care when observing the sky and never look directly at the sun with the naked eye, particularly with binoculars or a telescope! Be aware that although sun dogs may sometimes be hard to distinguish, they can be blindingly bright.

Sometimes they can be seen as part of a halo

A famous example of the appearance of a parhelion was during the wars of the roses. Three suns were seen to be rising at dawn prior to Edward IVs victory at the battle of Mortimers Cross. This good omen led him to

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No two snowflakes are the same because the crystal pattern of a snowflake is so dependent on tiny variations in the atmosphere and no two snowflakes take the same journey to the ground.

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DNA consists of two strands of sugarphosphate backbone held togetherby pairs of molecules calledbases


Cutting-edge chemistry

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A DNA barcode that can be added directly to food to enable it to be tracked and authenticated as it moves from farm to fork has been developed by scientists in Switzerland. The team showed that their system can track the milk used to make cheese or yogurt, and they say it could help authorities crack down on foodfraud.

DNA testing is already used to monitor food authenticity, explains RobertGrass from the Swiss Federal Institute of Technology in Zurich, whose team developed the DNA barcodes. Most techniques work with specific isotope patterns, which are characteristic for a given region, or natural DNA patterns, which are characteristic for a given species, he says. Our technology is different, as we deliberately add our label to the foodstuff. This allows us to discriminate products which are chemically identical, such as organic andnon-organic.

Adding and detecting DNATo make the barcodes, the team encapsulated short sequences of DNA, around 100 base pairs long, in silica particles (SPED) that protect the DNA when the food is processed. The DNA barcodes can be added to food at source and later detected in a sample using a technique called PCR. This technique amplifies the target sequence of DNA, so it can detect the barcode even at very low concentrations down to a few parts perbillion.

In a proof-of-concept study, Robert and his team added DNA labels to milk, and showed they could still be detected after it had been turned into cheese or yogurt. In principle our approach is possible with nearly all types of food, says Robert. We have also

been applying the approach to non-food products, including high grade polymers, glues and paints. He adds that the team are currently working on products that undergo more complex processing, such as tracing wheat that is turned into flour and then used to makebread.

Legal hurdlesIts a good piece of research, and an interesting application of the science, comments Duncan Campbell, a public analyst for West Yorkshire Analytical Services and past president of the Association of Public Analysts. But he warns there are various legal hurdles to overcome before the system could be applied to food sold forconsumption.

Before labelled products could be marketed there would have to be considerable changes to food additives legislation across the EU, he says. Even if the silica particles didnt have any DNA in them, silica is only permitted for use as an additive in certain foods and milk is not one ofthem.

He adds there is also a risk of members of the public objecting to the technology because of the addition of synthetic DNA to food. There is potential consumer opposition its got the makings of a tabloid scare story, hesays.

Robert agrees these issues could present difficulties in future. The main question at hand is if the risk of adding our technology to foodstuff can be balanced with the need for foodstuff traceability, he says. These are questions we cannot answer on our own they require an open discussion with the public and regulatory bodies.

EmmaStoye looks at an advance that could help keep your foodsafe

DNA barcodes used to trackfood

Stop press!An end to hors

e lasagnes?

Chemists in the UK have

developed a simple method

to distinguish horse meat

from beef using a benchtop

NMR machine.

http://rsc.li/1yzRndD

Base pair

Sugar phosphate backbone


January 2015 | The Mole | 7www.rsc.org/TheMole

practical approach. Previously theres been a lot of work that used aggressive etchants but this is a very attractive process where you end up with a clay-like paste that can be plastically formed in whatever shape you like, he says. Other supercapacitor materials like rutheniumoxide beat MXenes when it comes to energy storage; however, MXenes have an economic advantage. The elements we use are inexpensive. Unlike ruthenium oxides, the materials are available in large quantities and can be used on large scale, explainsYury.

His team is now working on MXenes other than titaniumcarbide, which is not necessarily the best performing one. The new method also allows us to make some MXenes we could not make before and it leads to different properties [in the known materials]. We have a large group of materials to explore, which is very exciting, Yury says.

A conductive clay made by US researchers might provide a novel way of storing energy that could, one day, surpass batteries. The team developed a cheaper, safer and simpler method to make supercapacitors, tripling the amount of electrical energy they can store.

Unlike batteries, which convert chemical energy into electrical, capacitors store energy as electrostatic potential similar to creating a static charge by rubbing a balloon on a jumper. Supercapacitors have a number of advantages over batteries in that they charge almost instantly, can release energy in large, quick bursts and are extremely durable. There are some applications where supercapacitors can already replace lithium ion batteries, for example in buses or cars, because of their fast charging time and good cyclability, explains YuryGogotsi from Drexel University in the US, who is part of the team that developed the new capacitorsynthesis.

MXeneIn 2011 Yury and colleagues discovered an entirely new family of two-dimensional supercapacitors, which they called, in homage to graphene, MXenes M being a transition metal and X carbon or nitrogen. The cheap material can store three times as much energy as standard carbon capacitors. However, MXene synthesis required hydrofluoric acid, which is highly toxic and corrosive.

Now, Yurys team have developed a simpler and safer protocol to make MXenes, using only dilute hydrochloric acid and lithiumfluoride. The team was surprised to find that when the known MXene titaniumcarbide was synthesised using this method it stored three times as much energy as the same material made by HF etching or six times as much as ordinary carbon capacitors. A somewhat unexpected result, admits Yury.

Play-Doh powerThe improved MXene was surprising in another way: it was soft like clay thanks to water in-between the materials sheets. The team could mould it into different shapes and roll it into thin sheets like biscuitdough.

Materials chemist MiloShaffer from Imperial College London, UK, likes Yurys

Katrina Kramer investigates a dough-like material with surprising energy-storing abilities

Conductive clay rolled out to store energy

practical approach. Previously theres been a lot of work

Find out more

Take a look at how MXene

is made and used with this

video from Drexel University:

http://rsc.li/1zZcKYj

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The improved supercapacitor recipe produces a soft clay that can be rolled out like biscuit dough


Dudley Herschbach, who won the Nobel prize for chemistry for his work in understanding the way molecules react, appeared on The Simpsons to present Professor Frink with his own Nobel prize.


Homer, Marge, Bart, Lisa and Maggie all have personal traits that combine to make each episode

Science writer SimonSingh has recently written about the maths in the TV show The Simpsons in his book The Simpsons and their mathematical secrets. For example, in the episode MoneyBart, Lisa is seen next to a book titled ei+1=0, a famous equation called Eulers identity. Simon talks about how many of the shows writers have mathsdegrees.

This might explain why the chemistry references in the show are neither as abundant or as accurate. In Bart the Genius, the Simpson son is seen preparing two chemicals. His teacher asks, You do know what happens when you mix acids and bases, dont you? Of course I do! replies Bart. As he mixes them together, a jet of green gunk erupts from the test tube and coats the room. This terrible misrepresentation of chemistry can be explained away as creative licence, but is it possible that the show could teach us something aboutchemistry?

There are roughly as many characters in The Simpsons as there are elements in the periodic table. According to the Chemical Abstracts Service registry, the 118 elements can be used to make more than 90 million unique organic and inorganic chemicals. Similarly, the one hundred or so permanent cast members of The Simpsons have been combined in different ways throughout the shows history to produce more nearly 600episodes.

Compounds of charactersThe Simpsons episodes are shaped by their composition, for example episodes with a high Lisa content explore moral themes. This is like the way that characteristics of a compound are influenced by the elements it contains. Large compounds rich in carbon generally make good fuels, such as carbohydrates and fats. Halogen-containing compounds are frequently used for hygienic purposes, such as sodium hypochlorite (NaClO) inbleach.

This is not the only interpretation possible for the airtime of different characters. Elements vary in abundance. The five most abundant elements in the Milky Way galaxy are hydrogen, helium, oxygen, carbon and neon. There is three times as much hydrogen as the rest of the top 10 put together. If Homer is the Simpsons character with the most air time, then he must represent hydrogen. His family members Marge, Bart and Lisa would be the next most abundant: helium, oxygen and carbon. Meanwhile, the characters that we enjoy only fleeting glimpses of, such as Bumblebee Man who only features for a few seconds in the episode 22 short films about Springfield, might represent an element like astatine, of which only about enough to fill a teaspoon currently exists onEarth.

The importance of being HomerElements also vary in their frequency of use. Millions of tonnes of iron, aluminium and copper are used each year to build things like buildings, cars, aircrafts and electrical circuitry. Carbon and hydrogen are also used heavily as they form the backbone of the polymers that are used to make plastics. Each member of the Simpson family could represent one of these useful elements, as they are such a key feature of theshow.

ChiefWiggum and MrBurns, supporting characters that often play a key role in the plot of an episode, might represent an element like gallium. This metal is used in many transistors, the electronic component that made the development of computers possible. Despite the importance of gallium, only about 273 tonnes were produced worldwide in 2012, compared to 16,800,000 tonnes ofcopper.

Finally, those rarely-appearing characters, such as the inept salesman Gill, might represent those elements for which no use has yet been found. Thanks to its 8.1-hour half-life, no use for astatine has been found outside ofresearch.

The Simpsons provides an interesting way to view chemistry. What the two things have in common is that a small number of building blocks can produce a dizzying array of different combinations. And what keeps us watching the many permutations of The Simpsons? The chemistry between the characters. What do you think?

The worlds favourite animated family gives us an interesting way to view chemistry. TomHusband explains

The Simpsons

Chemistry is like

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Andy has a soft spot for rubrene, the dye in yellow glowsticks

Dec 2013presentCompound Interest website

2013presentChemistry teacher at Bournemouth School, UK

20122013 PGCE in teaching chemistry, University of Bath, UK

20072011 BSc in chemistry, University of Bath, UK

2007A-levels in chemistry, physics and English

A few of his friends from his teaching course asked for

copies of the posters. Thinking the easiest option would

be to make a website where anyone could download

them, Andy uploaded his first infographics to the web

under the name CompoundInterest.

From there it bloomed, and got a little bit

out ofcontrol.

Today the site contains hundreds of

infographics about the elements and

the chemistry of everyday objects.

Andys infographics have been

featured on sites like Lifehacker and

the Guardian, and have even made their

way onto national television in theUS.

The interest in Andys designs has been so

widespread that later this year hell be publishing

The curious chemistry of food and drink, his firstbook.

Going undercoverDespite the success of his side-project, Andys students

are mostly unaware of his alter ego. A few of them have

found the site. I did tell a few of them about it as well,

some of the kids who are really interested in chemistry,

he says. In particular, if theres something they ask I can

say well, actually, Ive done something onthat...

Andy even plans to sneak a copy of his book into the

school library, just to see if anyone findsit.

I asked Andy if, after all the research hes done, he has

a favourite molecule. In terms of appearance, the glow

stick compounds look good, he says. Theres one

called rubrene, the dye in yellow glow sticks, that has a

very nice symmetricalstructure.

In terms of molecules that are just generally interesting,

I find molecules that are poisonous fascinating. But I

havent done many graphics on them,yet.

Andy keeps a list of ideas for new infographic designs

to hand so that he can jot down ideas whenever he

thinks of them. Sometimes the difficult part is finding

information on the chemistry. Im still working really

hard on finding some papers about wet dog smell. It

seems nobody has done a research paper onthat.

After finishing a degree in chemistry, AndyBrunning didnt know what he wanted to do. Eventually deciding on a career in teaching, he started to make posters about chemistry to brighten up his classroom.A year later, his chemistry infographics (images representing data) have been shared across the internet he even has a book comingout.

Andy studied chemistry at the University of Bath. When Id finished my degree I still wasnt entirely sure what I wanted to do. At that stage I applied for a few jobs in industry, but didnt really get anywhere with that, hesays.

Finding a pathAs a stop-gap, I ended up working for the student support services at the university. Andy attended lectures and took notes for other students who, for whatever reason, couldnt take notes for themselves. He also occasionally worked more closely with some of thestudents.

While I was doing that, I started to consider teaching and eventually decided to apply for the PGCE (teacher training) course atBath.

At the time I wasnt 100% sure that it was something I would enjoy or not, but I thought Id give it a go, Andy explains. It turned out be something that I really enjoydoing!

Its Andys curiosity for learning new chemistry alongside his students that drives his enthusiasm for teaching. Thats the part I really enjoy, the fact that I still feel like Im learning stuff as well as the students Im teaching. He adds, the challenging part is helping them to understand it when its something that doesnt click straightaway.

InfographicsWhen Andy started at his school in Bournemouth, UK, he inherited an old classroom lab that needed a bit of colour. It didnt have anything up on the walls, so I really wanted to get something interesting up there. His solution, despite having no previous experience in graphic design, was to make a few chemistry-inspired posters of his own. Really, the site came as a result ofthat.

PaulMacLellan talks to the teacher whose chemistry posters went viral and landed him a bookdeal

Teacher and infographicdesigner

Andy Brunning

Andy keeps a list of ideas for new infographic designs

January 2015 | The Mole

Take a look!

Check out Andys chemistry

infographics at Compound

Interest explorations of

everyday chemical compound

s

www.compoundchem.com

under the name

From there it bloomed, and got a little bit

out ofcontrol.

Today the site contains hundreds of

infographics about the elements and

the chemistry of everyday objects.

Andys infographics have been

featured on sites like

the Guardian

way onto national television in theUS.

The interest in Andys designs has been so

widespread that later this year hell be publishing

year later, his chemistry infographics (images representing data) have been shared

As a stop-gap, I ended up working for the student support services at the university.

A

NN

A V

IDO

S



ChemNet

| January 2015

Find out more

ChemNet is a free network fo

r

chemistry students, and we're

here to help you.

Come and visit us at

http://chemnet.rsc.org

Chemistry of drumming28 January 14:0015:00Longlevens, GloucesterExplore the science behind drumming, discuss the chemistry that underpins this physical art form and how drumming may be the secret to a healthy body and mind.

http://rsc.li/drumming

When chemistry and art collide

5 February 10:0013:30Piccadilly, LondonFind out how gravity, pendulums and paint can create unusual works of art. Come and see how chemistry and art collide in this hands-on workshop that is more than your average art lesson.

http://rsc.li/chemistry-art

How much gold is there in my jewellery?

10 February 10:3012:30Goldsmiths Hall, London Learn about cutting-edge techniques being developed to determine the purity of non-precious metals. Come and find out about a different side to chemical analysis.

http://rsc.li/gold

From toilet to Thames18 March 10:0014:30Kingston upon ThamesCome and see how the UKs largest water and sewerage company takes our waste water and cleans it before returning it to the Thames.http://rsc.li/toilet-to-thames

AaronKeogh, a PhD student at Trinity College, challenged the students with common misconceptions about scientists. Theres a perception that being a scientist is a lonely job, with lots of time spent alone in the lab. The reality, Aaron pointed out, is that scientists work in teams where communication and people skills are crucial for success. His face lit up when talking about the team he is part of, explaining to the students not only the need to clearly communicate findings to the whole group, but also the peer support and social network theyprovide.

Interested? Undecided?Like many of the other speakers, AineWhelans interest in chemistry was nurtured by her school teacher, but for a while she had no specific career plans or ideas. Eventually she built a career as a forensicscientist.

In her talk she described the role that problem solving plays in her job and the variety in her work from analysing samples from crime scenes to being an expert witness in court. I have really enjoyed the different experiences that have come my way so far as a result of studying chemistry. A career in chemistry has allowed me to travel and work in different countries and with lots of different people, from the police to marine biologists to semiconductorengineers.

At the end of a busy day we had three take home messages: you dont have to know exactly what you want to do in the future; scientists dont work alone or just in labs; and there are many careers from which you can choose! See where a future in chemistry can take you at www.rsc.org/careers/future.

What will you decide to be?

Science Week is Irelands huge annual celebration of science. Its a jam packed week of interesting and accessible events for children and adults and happens every November all across the country. To celebrate Irish Science Week the Royal Society of Chemistry and Trinity College Dublin brought together young scientists and successful Irish chemists to showcase the variety of careers a chemistry qualification can leadto.

Three hundred 16 and 17-year-old students from more than 15 schools across Dublin and further afield attended the event, which was supported by local high-tech employers such as Hewlett Packard, Henkel and the Irish National Forensic Science Laboratories. In addition, there were undergraduate students from Trinity College talking about the choices that are available for studying chemistry, such as taking science or chemistry in first year at Trinity and what it means to do aPhD.

Each speaker talked about their personal journey to their current role, describing their background and showing that not everyone knows exactly what they want to do at the start of theircareer!

Printers and perceptionsAndrewKavanagh from Hewlett Packard showed the variety of work that they are involved in, such as software, servers, computing and cloud storage. Its not just printers you know! Talking about his journey through a degree and a PhD, he advised students that he never had a specific career in mind, and that was fine. Now as chemical engineer at a world leading technology company he uses chemistry on a daily basis. Afterwards, Andrew said I hope I gave the students the idea that a career in chemistry can be diverse, exciting andrewarding.

Francine Atkinson takes a look at how a career in chemistry can take you from computers to crime scenes

Careers in chemistryDates for your diary

IA

IN W

HIT

E

IA

IN W

HIT

E



Our team of professional careers advisors are on hand to answer your questions about chemistry careers, option choices at 14 and 16, and university or vocational routes. They are ready to provide advice and help you make confident choices about your future.

http://rsc.li/1ur6cxJ

Dr Careers

is here to help Are you thinking of a

career in chemistry, or even in the wider field of science or engineering? You already know that work experience is a good idea everyone

tells you that.

But what if you cant find work experience in

a lab? Maybe your school is

offering you work experience in an office, shop or car showroom. How could that be any use for your future science or engineeringcareer?

Surprisingly, it can! Its definitely not a complete waste of a week or two of your life. You can make itrelevant.

Transferable skillsEvery employer wants to see transferable skills. These are skills like dealing with customers, working in a

team, solving problems, determination or not getting upset when things go wrong. You need these skills in anyworkplace.

The important thing is to be able to explain how you used those skills and how they relate to what you want to do in the future. Lets have ago:

Interviewer: Have you done any workexperience?

You: Yes, I spent two weeks in anoffice

OK, thats true. But what about going on tosay,

... and they were stocktaking, so we were extra busy. I could see how I was helping the team get through the extra work by turning up on time and followinginstructions.

Then you could go on toadd,

I know that chemists work in teams with different skills and responsibilities to complete aproject.

Now youve shown you know how chemists work and that you have the rightskills.

Goodluck!

Work experience is itrelevant?

DrCareers

Substances that have covalent bonding

tend to have much lower melting points than those with ionic or metallic bonding.

For example, calcium sulfide (with ionic bonding) has a melting point of 2525C and

calcium metal melts at 842C, but

covalently bonded sulfur melts

at just113C.

Does this mean that covalent bonding is the weak and weedy cousin of ionic and metallicbonding?

Absolutely not! The difference is not the strength of the bonding, but rather in their structures. Most covalent substances form small molecules. The strongly bonded molecules in a covalent compound are only weakly attracted to each other. When some heat energy is applied, these molecules can easily gain enough energy to start slipping past each other, so the substance quickly turns to a liquid. No covalent bonds have to bebroken.

In contrast, ionic compounds form giant lattice structures where the ionic bonding goes on and on in three dimensions. Metallic substances also form giant lattice structures. So to melt a metallic or ionic substance you need to actually break these bonds. This is why melting points in these substances are muchhigher.

If youve seen Finding Nemo, youll remember the sharks phrase, Fish are friends, not food. For chemists it should be, covalent bonds are strong, notweak.

Covalent bonds are strong, notweak!

DrChemNet

Absolutely not! The difference is not the strength of the

substances form small molecules. The strongly bonded substances form small molecules. The strongly bonded

applied, these molecules can easily gain enough energy applied, these molecules can easily gain enough energy

Chemistry helpStuck on a tric

ky topic at

school?

Dont forget you can post you

r

problems to DrChemNet:

http://rsc.li/1wmzpg8


Puzzles50 of vouchers to be won

AMPHIPHILICANTIBACTERIALATOMSBILAYERSBIOCHEMICALBONDSCELLCHEMICAL CHANGESCIRCLECONVOLUTED SHAPECURVESDICHROICDOMAINS

ELECTRONFLOWGOLDLIPIDLIPID MOLECULESMETALNANONANOSCALE CHANNELSNANOWORLDOPAQUEPHOSPHOLIPIDPORESRANDOM

REGULARSALTSCATTERSILVERSIMPLE TECHNIQUESPONGYSOLUTESSTRUCTURESWATERWAVELENGTHX RAYSZOOM

C S E L U C E L O M D I P I L L N

G O L D N S X E R E V L I S A A W

C D N M A E R U E L C R I C N O A

H I A V N T A Q Z O O M I O L I V

E P M D O U Y A C A R M S F L R E

M I P O R L S P T R E C S O E N L

I L H M A O U O E H A E B T C A E

C O I A L S M T C L V O T T I N N

A H P I U S A O E R N A L L O O G

L P H N G W I C U D C A M I R W T

C S I S E B H C S S S S E P H O H

H O L C R A N D O M O H T I C R Y

A H I P N O R T C E L E A D I L G

N P C N S R E Y A L I B L P D D N

G S E R O P S T R U C T U R E S O

E L L A I R E T C A B I T N A E P

S E U Q I N H C E T E L P M I S S

WordsearchFind the 38 words/expressions associated with membranes and nanotechnology hidden in this grid (contributed by Bert Neary). Words read in any direction, but are always in a straight line. Some letters may be used more than once. When you have found all the words, use the remaining letters to make a 10-letter word. Find out more about membranes twisted secret in The Mole, November 2013 (http://rsc.li/TM0613).

November wordsearch solution and winnerThe winner was Anja Armstrong from Grandtully. The 11-letter word was CONSISTENCY.

Submit your answers online athttp://bit.ly/TM115ans

by Monday 2 FebruaryA correct answer for each puzzle, chosen at

random, will win a 25 Amazon voucher.

Chemical acrostic

November acrostic solution and winner

The winner was Laura Capstickfrom Didcot

November acrostic solution and winner

The winner was Laura Capstickfrom Didcot

G A L L I U M

E R B I U M

C A R B O N

B R O M I N E

L E A D

A R G O N

I N D I U M

H E L I U M

C A D M I U M

All the answers are d-block metals

1 Only element in the d-block that is liquid at room temperature.

2 Metal used to manufacture corrosion resistant steel.

3 Most abundant d-block metal.

4 This metal is a different colour to all the other d-block metals.

5 A d-block metal that's not a transition metal.

6 Metal that forms ions with different colours in several oxidation states.

7 Metal used to catalyse reactions in both the chemical industry and automobiles.

Complete the grid (contributed by Simon Cotton) by answering the seven clues to find the answer in the shaded box. This will spell out the name of one of the family of six platinum metals.

Another clue For clue three: this element is

essential for human life. The human

body contains around 4 g, mostly

in the haemoglobin in red blood

cells. Haemoglobin carries oxygen

from our lungs around the body.

IST

OC

K

1

2

3

4

5

6

7

0115TM - Puzzle page.indd 12 12/18/2014 2:22:22 PM

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