Why Study Chemistry ?

 

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So I always knew it would happen, in the darkest days of the academic year the enthusiasm for blogging would wane. But as always social media through up a nugget to get me thinking again. This time it was a link to an Irish Times article about choosing the right degree course at university.

http://www.irishtimes.com/student-hub/course-decision-cannot-be-taken-lightly-1.2508463

In school I have recently been tidying up our careers notice board and I had contacted some past pupils doing science based courses and got them to write a piece on how studying chemistry helped them. In NI, as we are a small economy, there are only limited science career pathways for young people who want to build their lives here but what stands out from their pieces is their enthusiasm for their subject / chosen career. And that’s what the piece in the Irish Times highlighted – pick a subject or career that you have a passion for not just one that you think will serve you well.

So what jobs do people with chemistry degrees and PhDs end up in – if I look at the class of ( ok I’ll not reveal it but let’s just say we were all looking forward to that great millennium party!) my classmates have ended up in both the public and private sectors. Within the public sector there are teachers (both at secondary and tertiary level) and those in areas such as the Environment agency and Invest NI. In the private sector many got jobs in Ireland’s growing scientific sector, in particular Almac, Norbrook, Randox, Pfizer and BMS to name a few. I know some of the people who read this blog are friends and in particular those who I studied with so I’ll leave the floor open to you – would you advise your younger self to study a science based degree ?

On This Day …….

What’s in water ? Well everyone knows it’s a compound containing hydrogen and oxygen. But of course that was not always the case, in fact water was considered one of the four elements in ancient Greek philosophy. So how did we come to realise that water was a compound and not an element, and how did we learn what it was composed off ? On the RSC ‘On This Day in Chemistry’ website  it reports today that on 15 January 1784, the scientist Henry Cavendish announced the composition of water to the Royal Society.  He presented the results of experiments where he had burned dephlogisticated air (oxygen) and inflammable air ( hydrogen) together observing a dew had formed on the apparatus. The inflammable air was produced by reacting acid with a metal which of course is how we produce hydrogen in our practical classes today. With further experiments he discovered that twice as much hydrogen is required than oxygen.

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Cavendish was not alone on working on experiments to produce water, Joseph Priestley had also observed water in experiments (using ordinary air instead of oxygen) and Antonine Lavoisier also claimed to have discovered water. James Watt was Cavendish’s most serious contender for the discovery. Watt, a Scottish engineer, had a passion for steam engines and in his investigations to make them more efficient he also claimed to have discovered the composition of water. Cavendish was seen as a chemist whereas Watt was considered more of an inventor so two camps formed with their supporters and the ‘Water Controversy’ began. Interestingly,  the debate centred around the fact that Watt had established the concept of water as a compound before Cavendish produced the experimental data. Cavendish, who was always slow to publish due to his crippling shyness, eventually won the battle as later studies of his notebooks attributed the discovery to him.

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Henry Cavendish Portrait

Cavendish was a complex individual who had great problems with social interaction which some now believe may have been autism. As with scientists of his time Cavendish worked in other fields such as electricity, the density of the Earth and even thermodynamics (James Watt also patented an idea that could be seen as the fore runner to the photocopier and also coined the term ‘horsepower’). At that time there was not the clear division between physics and chemistry that is seen today – a relative later donated funds for the Cavendish laboratories at Cambridge university. These are found in the Physics department and are probably one of the most famous sets of labs in the world producing a host of Nobel prize winners including Thompson, Rutherford, Watson and Crick to name a few. Because Cavendish was concerned with science for understanding not for profit at the time he was considered a ‘gentleman of science’ and I think that is a fitting tribute

 

Waiting for a Bus !

It’s a bit like buses, you wait for ages then four come by at once. Of course the big news story this week is the positive identification of four new elements 113, 115, 117 and 118. (For those of you a long time out of the classroom this number is the atomic number which is the number of protons found in the nucleus). The actual names for these elements are up for discussion with debates over whether they should be after people, countries, minerals or places to name a few suggestions. There have been lots of articles about these elements, a great graphic by compound interest and an excellent blog post by Dr Eric Scerri.

http://blog.oup.com/2016/01/four-new-super-heavy-chemical-elements/

It popped up as a question on the BBC quiz show Pointless and I even spotted a petition on Twitter to name element 117 octarine in honour of Terry Practchett. Oh and my favourite -naming one after Lemmy, the bassist of the heavy metal band Motörhead.

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But what I want to talk about is the island of stability. In nuclear physics, the island of stability is the prediction that a set of heavy isotopes with a near magic number of protons and neutrons will temporarily reverse the trend of decreasing stability in elements heavier than uranium. Now magic is not something that you usually hear scientists talk about but it refers to the numbers of protons and neutrons that give stable atoms. It goes against everything we’ve been taught in that as nuclei get bigger they get more unstable, and that any element greater than uranium in the Periodic Table does not occur naturally. So where do we find this island and why an island ? If you look at the graphic above which is the relationship between nucleons and stability and use a bit of blue shading it becomes clearer. The island of stability is a region of the periodic table where elements’ half-lives increase after a large group of elements with very short decay times. This is were we find the super heavy elements who have atomic numbers greater than or equal to 112. The discovery of element 114 back in 1998 was the beginning of the this quest for the island of stability. And why are some of these super heavy elements stable – I think I’ll leave that to the nuclear physicists to explain.

Making these super heavy elements is no mean feat and there are only certain places in the world with the capabilities to do so including the RIKEN Institute in Japan, Joint Institute for Nuclear Research in Russia, and Lawrence Livermore and Oak Ridge national laboratories in the U.S. These elements have been reported in the literature for quite a while now with first experiments on 113 and 115 starting in 2003. To create these elements researchers smash smaller elements together. For instance, to make element 117, calcium nuclei (20 protons) were smashed into a target of berkelium (97 protons). Interestingly they never actually recorded the new element itself but evidence of its decay products. Why bother spending so much time making these elements that really do not have any everyday uses – it’s that old science chestnut, we add to the bank of scientific knowledge and we learn a bit more about atomic structure. As some may have longer half lives we may be actually able to do experiments with them and one day who knows where that could lead !

Fancy a job on the International Space Station ?

One of last years most fascinating tv programmes was the Horizon special on the ESA astronaut Tim Peake. Even though chemistry is my thing space continues to fascinate and inspire me. Whether it’s the Mars rover or the disappearance of the ESA Beagle I always try and mention newsworthy space stories in a lesson. There is an excellent YouTube clip from NASA about the scientific machinery on board Curiosity, including a mass spectrometer, and I find it an excellent introduction to Mass spectroscopy at AS level. Recently I blogged about growing crystals and believe it or not this is one of the tasks of an astronaut during their time on the International Space Station.

Growing crystals in microgravity has long been a focus of space science. I can remember the Saturday night clearly in 2003 when news broke that the space shuttle Columbia had exploded on its re-entry into Earth’s atmosphere. At the time I was completing my teacher training and also working part time as an editorial assistant for the American Chemical Society journal ‘Crystal Growth and Design’ (working for a peer reviewed journal is totally a post all on its own). So as the news filtered through and I began to understand what Columbia’s scientific mission had been about, the enormity of the tragedy resonated with me. The Columbia Space shuttle was on a mission to complete lots of science in microgravity. This included growing crystals, combustion studies and the development of stronger, more resilient metals and alloys. The Columbia space shuttle was essentially a science lab in space and the seven brave astronauts were trail blazers for the scientific community.

 

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So why grow crystals in space? Space grown crystals are of greater purity than those grown on Earth and have more highly ordered structures which significantly improves their X-ray analysis. There has been a focus on growing protein crystals in space. Protein structural information plays a key role in understanding biological interactions. Scientists discover new drugs now by understanding the orientation and connectivity of the atoms within a molecule and how this drives its interaction with atoms in another molecule (for example an enzyme that might be able to be ‘switched off’). This allows for the development of new pharmaceutical treatments for both chronic and acute illnesses such as lymphoma , psoriasis, rheumatoid arthritis, AIDS and influenza to name but a few. The International Space Station provides an opportunity to have a complete crystallographic capability which was previously not possible with the space shuttles.  The role of the astronaut is changing – the Space agencies need astronauts who understand the science. There are amazing opportunities for our next generation of scientists to be groundbreaking – not on Earth but in Space – helping to cure the illnesses that blight us humans.

 

p.s. Here is a good activity for growing crystals from NASA

http://www.nasa.gov/pdf/675572main_Science%20Activity-SOS.pdf