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Should the periodic table be turned upside down?

Chemistry beakers

Isabel, Y10, explores the comprehensibility of Dmitri Mendeleev’s traditional periodic table and whether it would be more accessible for younger children and enhance learning methods if it were flipped around by 180˚.

The Periodic Table is an important symbol in Chemistry and since Dmitri Mendeleev’s discovery of the Periodic system in 1869, it has remained the same for 150 years; but could turning it 180˚ make important concepts easier to understand, especially in teaching younger children?

This year has been announced the Year of (Mendeleev’s) Periodic Table which has become the generic way of arranging the elements. However, some scientists like Martyn Poliakoff and his team have started to question the comprehensibility of it. After extensive research, they decided to flip the traditional arrangement upside down, so that the information is more understandable and intuitively ordered.

The research team argues that this presentation is more helpful and has many benefits. Firstly, when the table is flipped the properties of the elements such as atomic mass and proton number now increase from bottom to top therefore making more numerical sense. Secondly, it represents the Aufbau principal more accurately, which states that electrons fill up ‘shells’ from low to high energy. Finally, when young children are trying to learn from the table, the more relevant elements to them are located towards the bottom of the table, making its use quicker and more accessible. Therefore, in lessons, students will not have to look all the way to the top of the table to be able to find the right information.

Above: Inverted Periodic Table. Source: University of Nottingham
Above: Traditional Periodic Table

However, when I compared the two versions of the periodic table myself, I found that the traditional form of the table made more sense to me for many reasons. For example, in both situations I found my eyes drawn to the top row of elements, so it did not matter that the elements that I use the most were on the bottom row. However, this could be put down to a force of habit, so I also asked my 10-year-old brother to look at the two perspectives of the table and see where he looked. He immediately pointed to the top of both and when I asked him the reason he said that from top to bottom ‘is the way you read’ so the properties make more sense going down from top to bottom. He also seemed to prefer the traditional table, commenting that it was like a ‘pyramid’ in the way the numbers were arranged and was a much clearer way to display the elements.

Whilst some may argue that the arrangement of the table is more effective if it were upside down, for me the traditional version of the periodic table works just as well. Testing this principle to a larger group will allow different models to be tried to see if it makes understanding the periodic table easier for younger learners.

References:

Martyn Poliakoff et al, Nat. Chem., 2019, https://www.nature.com/articles/s41557-019-0253-6

 

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The Brain Chemistry of Eating Disorders

Jo, Year 13, explores what is happening chemically inside the brains of those suffering from eating disorders and shows how important this science is to understanding these mental health conditions.

The definition of an eating disorder is any range of psychological disorders characterised by abnormal or disturbed eating habits. Anorexia is defined as a lack or loss of appetite for food and an emotional disorder characterised by an obsessive desire to lose weight by refusing to eat. Bulimia is defined as an emotional disorder characterised by a distorted body image and an obsessive desire to lose weight, in which bouts of extreme overeating are followed by fasting, self-induced vomiting or purging. Anorexia and bulimia are often chronic and relapsing disorders and anorexia has the highest death rate of any psychiatric disorder. Individuals with anorexia and bulimia are consistently characterised by perfectionism, obsessive-compulsiveness, and dysphoric mood.

Dopamine and serotonin function are integral to both of these conditions; how does brain chemistry enable us to understand what causes anorexia and bulimia?

Dopamine

Dopamine is a compound present in the body as a neurotransmitter and is primarily responsible for pleasure and reward and in turn influences our motivation and attention. It has been implicated in the symptom pattern of individuals with anorexia, specifically related to the mechanisms of reinforcement and reward in engaging in anorexic behaviours, such as restricting food intake. Dysfunction of the dopamine system contributes to characteristic traits and behaviours of individuals with anorexia which includes compulsive exercise and pursuit of weight loss.

In people suffering from anorexia dopamine levels are stimulated by restricting to the point of starving. People feel ‘rewarded’ by severely reducing their calorie intake and in the early stages of anorexia the more dopamine that is released the more rewarded they feel and the more reinforced restricting behaviour becomes. Bulimia involves dopamine serving as the ‘reward’ and ‘feel good’ chemical released in the brain when overeating. Dopamine ‘rushes’ affect people with anorexia and bulimia, but for people with anorexia starving releases dopamine, whereas for people with bulimia binge eating releases dopamine.

Serotonin

Serotonin is responsible for feelings of happiness and calm – too much serotonin can produce anxiety, while too-little may result in feelings of sadness and depression. Evidence suggests that altered brain serotonin function contributes to dysregulation of appetite, mood, and impulse control in anorexia and bulimia. High levels of serotonin may result in heightened satiety, which means it is easier to feel full. Starvation and extreme weight loss decrease levels of serotonin in the brain. This results in temporary alleviation from negative feelings and emotional disturbance which reinforces anorexic symptoms.

Tryptophan is an essential amino acid found in the diet and is the precursor of serotonin, which means that it is the molecule required to make serotonin. Theoretically, binging behaviour is consistent with reduced serotonin function while anorexia is consistent with increased serotonin activity. So decreased tryptophan levels in the brain, and therefore decreased serotonin, increases bulimic urges.

Conclusions

Distorted body image is another key concept to understand when discussing eating disorders. The area of the brain known as the insula is important for appetite regulation and also interceptive awareness, which is the ability to perceive signals from the body like touch, pain, and hunger. Chemical dysfunction in the insula, a structure in the brain that integrates the mind and body, may lead to distorted body image, which is a key feature of anorexia. Some research suggests that some of the problems people with anorexia have regarding body image distortion can be related to alterations of interceptive awareness. This could explain why a person recovering from anorexia can draw a self-portrait of their body image that is typically 3x its actual size. Prolonged untreated symptoms appear to reinforce the chemical and structural abnormalities in the brains seen in those diagnosed with anorexia and bulimia.

Therefore, in order to not only understand and but also treat both anorexia and bulimia, it is central to look at the brain chemistry behind these disorders in order to better understand how to go about successfully treating them.

 

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Engineering – Take a closer look

Alex Farrer, one of our Scientists in Residence, looks at the value of science capital and the potential that this can have on future careers in the sciences.

Engineering 2018

2018 is the Year of Engineering – a government campaign to support the engineering profession in recruiting tomorrow’s engineers. Over the last 30 years efforts to attract girls and women into engineering have been unsuccessful. Currently less than 1 in 8 of the engineering workforce is female; boys are 3.5 times more likely to study A level Physics than girls; and boys are five times more likely to gain an engineering and technology degree (Engineering UK 2017).

Our STEAM focus at Wimbledon High provides insights into a variety of opportunities in engineering and in related areas such as design, sports, medicine and computer science. Through STEAM we strive to broaden what counts as science and help build the skills that future employers will value highly such as communication, problem solving and adaptability. We aim to encourage all pupils from Reception to Year 13 to think that STEAM is relevant and important to their lives, both now and in the future, and aim to build their science capital.

A national survey of young people aged between 11 and 15 found that 5% had a high level of science capital (ASPIRES projects).

Professor Louise Archer from UCL Institute of Education, directs the ASPIRES projects and has developed the concept of science capital which refers to someone’s science related qualifications, understanding, knowledge, interests, attitudes and contacts.

The Science Capital Teaching Approach aims to build on the existing science capital of pupils, encourage engagement with science and promote social justice.

If you have a high science capital you might:

  • watch scientific TV programmes
  • have science qualifications
  • enjoy reading popular science books
  • have friends and relatives that work in science and engineering professions
  • visit science museums and fairs
  • engage in science related hobbies or activities
  • talk about science and engineering news topics with people you know

The evidence from this research project shows that the more science capital a pupil has the more they will aspire to continue with sciences post-16 and see science and engineering as fulfilling roles.

Below are some suggestions that schools could consider to build the science capital of pupils and adults in their communities so that everyone sees science and engineering as something of value.

  1. Host a family STEAM challenge event. This will help to encourage science talk with family members and show that STEAM is for everyone in the school community.
  2. Encourage science and engineering activities to “pop up” in the playground. Pupils, parents or staff could run the activities and the high visibility will encourage all members of the school community to get involved.
  3. Celebrate interest in scientific TV programmes and films. For example show a screening of a film like Hidden Figures with scientists or historians on hand to answer any questions, or encourage staff and pupils to talk about the science on TV they have seen.
  4. Signpost STEAM books, magazines and events to staff and pupils. An example is Itch by Simon Mayo, which contains a great deal of chemistry, and there are also some excellent science magazines such as Whizz Pop Bang and BBC Focus that can be linked to lesson content.
  5. Think about ways to get families talking about STEAM homework that is set. Linking tasks to science or technology in the news will encourage talk as will setting tasks where help from adults is very much encouraged such as making a marble run, growing a mystery seed or taking a STEAM photograph.
  6. Find out the sorts of science interests, hobbies, and expertise pupils and their families have so that lessons and assemblies can be personalised. Setting a “Science and me” homework will heWHS Gymnasticlp to discover how many parents and pupils you have in your class with scientific interests and skills.
  7. Elicit and value the wider links that pupils have to science and engineering and draw upon them in lessons. For example using the experience of a gymnast in your class in a physics lesson will enable pupils to broaden what they thinks counts as science in their life.
  8.  Invite scientists and engineers that pupils will relate to into lessons and encourage them to talk about the skills and attributes they use. This could be a parent who uses STEAM skills in their job, a STEM Ambassador or someone who has relevant interest and knowledge. Even better if the scientist or engineer visits a lesson other than science! @STEMAmbassadors

Science lesson Wimbledon

If you are a primary teacher and would like to find out more about how you can build science capital in your school we will be hosting a Science Capital Workshop on February 7th 1.30-3.30pm. Please contact joanna.sandys@wim.gdst.net if you would like to come along.

If any parents with STEAM expertise would enjoy sharing some of their knowledge, skills and insights with our pupils please do let antonia.jolly@wim.gdst.net know and we will be in touch.

We look forward to enriching the science capital of our community in this exciting Year of Engineering as our STEAM journey continues.

Follow @STEAM_WHS on Twitter – #YoE

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O Chemistree, O Chemistree: The Wonder of Chemistry at Christmas

By Georgina Hagger, Year 12.

In this article I will endeavour to convince you of the magic of Chemistry, through Christmas related examples, and why we should all care a little bit more about not only the science itself but its contribution to our daily lives.

It’s the most wonderful time of the year, and whilst we all enjoy the lights, presents and the much-anticipated food, the reason behind all of these is forgotten. What makes your turkey go brown, what makes the smell of Christmas trees so enticing and what do your wrapping paper and Sellotape all have in common? To answer all these questions, we need one thing only: Chemistry. Chemistry is what makes this time of the year so enjoyable and yet it is overlooked, ignored and underrated.

When cooking many foods, a reaction called the Maillard Reaction is undergone: such is the case with the iconic Christmas Turkey. This is a chemical reaction between reducing sugars (for example glucose) and amino acids, and the different combinations of these two components is what makes the many different flavour compounds produced in this reaction. In turkey, some of these compounds are furans which produce the meaty, burnt flavours and also pyrazines for the cooked, roasted flavours. This reaction is what makes crisps go golden brown, along with giving some meat its brown colour, as melanoidins are formed which contribute to the brown colouration in cooking.

The smell of Christmas Trees, and pine trees more generally, is much-loved. This scent comes from three main compounds; the two types of pinene (alpha-pinene and beta-pinene) and bornyl acetate. It is this bornyl acetate that produces the pine smell, making it commonly used in fragrances and air conditioners for that fresh aroma. This smell originates from the just three elements that the compound is made from: carbon, hydrogen and oxygen.

When giving a gift at Christmas, or any other time of the year, the wrapping of the present is an important part. Whilst, wrapping paper and Sellotape do not immediately seem to be that similar, they are in fact both based on the same fundamental compound, the very same compound that gives plants their strength: cellulose. Whilst Sellotape needs an additional adhesive element to it, these two items are largely similar.

These ideas are all easy to understand, yet they are never talked about. Chemistry is simply defined as “the branch of science concerned with the substances of which matter is composed” and then how these substances react with each other. When the discipline is defined in such a way it is hard to see how this cannot be part of our everyday lives. Rosalind Franklin, the brilliant and unfortunately often forgotten chemist, once said:

“Science and everyday life cannot and should not be separated.”

However, we seem to have strayed from this, and now Chemistry is just for the people in white coats and goggles, whilst the vast majority of the others, according to a 2015 survey by the Royal Society of Chemistry, seem to only associate the subject with their school days and scientists. Yet we take selfies on our lithium powered smart phones, brush our teeth with our fluoride filled toothpastes and cure headaches with medicine without even knowing how any of this actually happens.

You may now ask, why do we need to know about Chemistry? And there are so many answers to that question; the emergence of disciplines like Green Chemistry to combat the disastrous effect we have on our planet and the shortage of engineers in this country alone, means more Chemists are needed now than ever before. As well as this, there is the simple answer of why should people not know, why should everyone not have the chance to understand the world around them? In recent weeks we have seen guides written by scientists, including chemists, to explain the use of scientific methods – such as DNA fingerprinting – to judges in order to aid better understanding of the chemistry that is used to prosecute and defend people in court. This is just one example of how chemistry is returning to the forefront of society and so needs to be understood.

By encouraging the sciences, and encouraging the explanation of the chemistry we all use; this makes one area of science so much more interesting and accessible to everyone. If everyone can hear about how this discipline is connected to their current situation through the engaging explanations of something like Christmas or cooking or electronics, then perhaps less people will feel marginally indifferent about Chemistry and more will feel interested and passionate about a subject that richly deserves and needs it.

So, as you pull a cracker this Christmas, become disgusted at the bitter taste of a brussels sprout, or watch the fireworks explode at New Year, remember to think about why and how these things happen and add a little bit of Chemistry induced magic to your life.

Follow @Chemistry_WHS on Twitter.

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Classic Chemistry Clips – The Beauty of the Practical

By Anthony Kane, Teacher of Chemistry.

Chemistry is, fundamentally, a very exciting and dynamic subject.

Part of the reason for this is the practical work we undertake – this takes two main forms, the class practical and the teacher demonstration.

When thinking about chemistry demonstrations, most students (past and present) will think of bangs, explosions and fire – all good things, but all over rather quickly. Some of you might remember, as I do, the disappointment when a teacher got you excited for a demonstration, only to watch it fizzle, sputter, and their subsequent and despondent “it wasn’t supposed to do that…

Imagine if we could replay, in slow motion, our favourite demos, to watch the magic of reality unfold frame by frame. Imagine always being able to see the demonstration clearly, regardless of where you were in the class. Imagine if we had a backup in case a demonstration, for whatever reason, went awry. Imagine if we were teaching a different topic entirely, and felt that now would be a wonderful time to illustrate our point with a display, but there was no time to throw it together. (Imagine if you wanted to show all your friends really cool science videos…)

These were the ideas that I had in mind when I started recording demonstrations during lessons at Wimbledon High School. Since then I have put together a catalogue of over twenty videos of common classroom demonstrations, and played them countless times. Using our Windows Surface Laptops, and connecting wirelessly to our SmartBoards, I am able to project what I am recording while it is being recorded.

The advantages are huge. Twenty students cannot all see one small beaker on a desk, but project it to the room and they can all get a perfect view. Sometimes the eye is not quick enough, or we blink, but with a video, we can go back and watch it again. We can slow it down, we can analyse frame by frame, and our learning is richer for it.

“Boom” goes the thermite.

Another aspect of the videos that I think particularly embodies the spirit of learning here at Wimbledon High is the sheer joy that students find in watching these demonstrations. “Ooh”s and “Ah”s are just as gratifying on recording as they are the first time you listen to them live in a lesson. One of our stated aims here at Wimbledon High is to nurture curiosity and a sense of wonder, and listening to some of the clips below, I hope you would agree that we are doing just that.

“Woah!”

“WOAAAAH!”

 

 

Where does this leave the future of chemical education? I think that the next logical step would be to record the method of class practicals – so that these videos can be distributed to students in advance of lessons and set as required viewing for the lesson. This would empower students to feel more confident with their equipment, have more time in the lesson to gather data, and to have more belief in their own abilities as scientists, encouraging their independence as learners. This would also prepare them well for scientific disciplines at university, which often require you to familiarise yourself with pre-lab exercises before entering a laboratory.

This is also a promising avenue for developing school partnerships. These videos are broadly applicable to many chemistry curricula, and we are fortunate at Wimbledon High to have excellent facilities and lab technicians. Sharing the fruits of our chemical labour is quick, easy, and importantly very beneficial to the education of others. I have already begun sharing my collection with another school and look forward to increasing their reach as time goes on.

Science is a practical discipline, and chemistry is a particularly visual subject. By offering students more opportunities to experience its beauty we open them up to a world of possibilities; an exciting pathway to deeper understanding of the universe, a subject both big and small, with deep history and philosophy, heroes and villains, and instil in them a lifelong appreciation for nature.