It has been a busy summer. I had better come back to the blog. I have been asked to contribute (amongst other contributions) to a Royal Society of Chemistry  book on Creative Chemistry. I jotted down some thoughts and sent them back. It has been edited well but I thought it might be useful to add more here.

In school staff rooms the “Arts Teachers” claim (in a friendly way I find) that their subjects are more "Creative" because you need to express yourselves with originality. In science, they say, answers are just right and wrong. (I wish they were sometimes.) I understand what they mean but even the great painters, authors, poets, actors etc, have “stood on the shoulders of giants”, just as Isaac Newton, Albert Einstein etc have done.
Creativity is how you use techniques and discoveries made in previous generations, either in painting, poetry to explore and explain ones innermost feelings or in chemistry and electrical engineering to solve new problems. In science education, teachers need to be creative to allow students to understand the world around them, especially connections between various fields of science and engineering (and also economics). I have always stressed that teachrs should create their own schemes of work and not rely on course books. Every school, every class is different.

Where practical chemistry work is possible in schools (such as the UK, students are often using the same procedures as their parents and possibly, even their grandparents did in school chemstry. Even if the presentation of lessons vary as in flipped, controlled investigation, sage on the stage, guide on the side etc, when it comes to procedure, methods hardly ever change.
Some of our standard practical procedures are up to 140 years old, can be found in old text books and are repeated in updated editions. Authors may be working from home with no access to the lab and in any case, practical procedure research can be very time consuming.
Continual repetition of these procedures takes no account of the changes in curriculum, examination specifications, education management, new equipment and materials, changes in safety legislation, environmental concerns, practical activities in university chemical education and information from research in chemistry education.

These were developed in the USA to address green and waste issues and in South Africa to spread practical work, via UNESCO, to countries with limited resources. The kit was given to all UK schools by the RSC in 1999 along with a practical book. There were a few pockets of interest, but not many. It looked alien to eyes of many teachers at that time.

Many teachers and academics think that CLEAPSS in the UK (http://science.cleapss.org.uk/ ) is just a safety police; we go around saying "don't do that!”. However, safety  is only part of the remit. CLEAPSS development work centres on enabling teachers and technicians to deliver enjoyable, interesting activities which are safe (and legal) to perform. The Practical Procedures (PPdocs) are on the website for subscribers. These are also presented to teachers and technicians via courses run in England, Wales and Northern Ireland with SSERC doing much the same in Scotland. The revision of a procedure or new experiment should,

• address activities that have caused safety issues such as toxic gas release, burns, explosions, etc,
• reduce the cost of expensive equipment by an alternative design or modern materials,

• address issues raised by UK safety legislation, usually designed for industrial purposes, but legally applying to school practical work,
• speed up practical work so that classroom management is more efficient,
• be directed to clarify an aspect of chemistry which causes confusion in students  (misconceptions) and
• try to reduce time and effort in preparation and waste procedures.

To do this, one needs to be “creative”. However, there are objections by teachers (not so much by technicians) to any new procedures whether the adjustments are normal scale or microscale such as;

• they would hamper students in answering questions exam questions based on older methods,
• they are not the exam-"required" method, even though the new method is more efficeint and more successful; also there is no requirement to do the published method, practical skills are required, and
  
• statements about microscale procedures such as “it is not proper chemistry”, “how can you do quantitative work”, “we have the proper equipment, why change?”, “it is for poorer countries” and “how can you demonstrate microscale chemistry?”
  

With stricter implementation of safety legislation and more cases of civil action by the parents of injured students and some teachers and technicians too, some employers wanted to ban certain chemicals and procedures. CLEAPSS do not want to ban, but enable safer procedures.
The developed microscale experiments have been presented in CLEAPSS safety talks, workshops and at ASE conferences. Visitors to CLEAPSS are shown the techniques in our laboratory. With interest finally shown from our examination boards, the techniques have become more popular.
The enthusiasts then began to report unexpected benefits.

1. Lab room management was less stressful..
2. Students were more focussed and not side-tracked by other student groups.
3. Mistakes were quickly and safely corrected.
4. The practical sessions were completed in the time available..
5. The results were visually pleasing, could be photographed and inserted into the lab book for future reference.
6. The use of webcams, visualizers and USB microscope allow dramatic demonstrations.
7. There was a reduction in the overload of the short-term working memory and so students were not asking “what do I do next?”
8. The practical work could be focussed on addressing known misconceptions and difficult areas in chemical education.
9. Completely new and interesting experiments could be developed

Sudden inspirations and “eureka” moments do happen when an idea comes together but there are many failures along the way. I have over sixty years of experience in school practical work (man and boy). I started looking for alternative procedures as early as 1993 for CLEAPSS and it was not for another 10 years that I realised I was creating something new and accessible. All the time I was building on the work from other sources such as  Nuffield Chemistry, Education in Chemistry, Journal of Chemical Education and School Science Review (Association of Science Education) and various sources on the web with the Bruce Mattson Microscale Gas Chemistry really acting as a catalyst.  Also from from like-minded people in other countries such as the USA, Germany, China, Japan, South Africa, Thailand and Malaysia who meet every two years.
There is added creativity in adjusting or modifying what occurs in these countries to the chemistry required in the England GCSE and A level. SSERC (in Scotland) have also developed microscale techniques alongside those from CLEAPSS. Here are some examples.

This is only made possible by using plastic folders or  laminated worksheets. The idea came from the RSC book on microscale chemistry but they used Overhead Transparency Sheets. The advantage with folders and lamination is that instructions can be asily seen and followed.
A puddle of water is about 1.5cm diameter. The volume of liquid is less than 0.8cm³. The picture shows the the colours of buffers with different indicators and then combining the indicators to prepare a Universal Indicator
Displacement and precipitation reactions can be investigated. Basically, the test tube is replaced by  the puddle.
Solutions can be used but it is a better teaching point to push the solid directly or introduced it on the end of damp pointed sticks,letting the solid dissolve and the solvated ions diffuse. See video below.
This resulted in a paper (and front cover) of the the May 2019 edtion of the Journal of Chemical Education.
(Bob Worley, Eric M. Villa, Jess M. Gunn & Bruce Mattson* J. Chem. Educ. 2019, 96, 5, 951-954)

Chemicals contain small invisible particles in random motion. We can see the results of any interaction between these particles in chemical reactions by changes of colour, solids appearing, changes in temperature etc. Diffusion can only be explained by particle theory but is introduced very early in the UK curriculum but then hardly reappears. In fact, some modern syllabuses do not mention “diffusion” at all. I can see that it is implied in other specifications. Possibly, diffusion appears so obvious to teachers/examiners that we miss it out. Yet research shows it is a very difficult concept for students to understand..

Based on original ideas in China and the RSC book, the use of small Petri dishes (never previously used in chemistry and quite alien to teachers with a traditional outlook) allowed the use of puddles with diffusion. The normal scale electrolysis of copper and sodium chlroide had exposed students to chlorine and they had been taken to hospital with breathing difficulties. Microelectrolysis of 0.5M copper chloride solution only produces around 6 cm³ of chlorine gas and yet, this is enough to carry out reactions on damp blue litmus and “puddles” of 0.1M potassium iodide solution and 0.5M potassium bromide solution. Finding more robust electrodes of 2mm medium wall carbon–fibre rods improved the procedure.

I then generated gases in Petri dishes chemically and produced amazing diffusion halos as in the example below with ammonia molecules in the Petri dish diffusing into a puddle of 0.1M hydrochloric acid with Universal Indicator. This is followed by hydroxide ions diffusing though the liquid, neutralizing the acid. These prcedures only take a few minutes.
So it has been quite a year with the chemcial halo poster winning the RSC Twitter Poster Competition for Further Education. AS you can see in  the poster, other halos are avialable.

My efforts in creativity pale into insignificance when compared to that of John Bradley in inventing the Radmaste kits, promoted by UNESCO. Yes, they have been used worldwide but they have come up against the same barrier as microsale in the UK, Traditiionally trained curriculum advisers and exam setters do not accept the changes. The initial enthusiastic users of the kits come up against lack of finance in maintainance of the kits and continued professional development..

I sometimes wonder about this although I am assured by many that it is a part of chemcial education research. However, barriers are put in the way of presenters when trying to present these procedures at important international meetings.

• The venue is not a University but a hotel (Hotel safety officer objects!).
• The venue is not in the chemistry department of the University. (University safety officer objects)
• The chemistry department is a some distance from the venue.
• Safety is run on Hazard Assessment as opposed to Risk Assessment. (Chemistry safety oficer does not understand microscale techniques)
• A University risk assessment proforma, designed for research is not applicable to this type of chemistry.
• Sorry to say but many of those who lead chemical education research from various countries are visible by their absence from practical workshops, by not taking part and not even visiting them.
  
• How can you see microscale? Well most venues have excellent IT facilities such as visualizers and split screens upon which the experiments can be displayed. So lecture demonstrations are possible.
  
• Journals demand evidence of the effectiveness of the work on students as well as a direct technical account of a new procedure. I can see that this is jumping through hoops in many cases. I prefer to let teachers see the results on Twitter and You tube. It is more immediate and effective than writing in a peer-reviewed journal, which teachers cannot easily access anyway.  When teachers see these experiments or used them in workshops, light bulbs come on in their minds.

Now when that happens, the teachers become creative. Creativity should be catching because I hope they are going to stand on my shoulders.

I have been very lucky. I have always found these halos visually exhilarating so I produced a poster about them for the 2019 Royal Society of Chemistry Twitter Poster competition in teh Chemcial Education Category .Then this came through the emails.
We are delighted to let you know that you have been awarded  Further Education prize in #RSCEdu for your poster entitled; "Chemical halos - the beauty of chemistry"
The subject chairs thought your poster really stood out and contained some fantastic science – congratulations!

Catching the students’ imagination through practical work is one reason teachers do it. Going that extra mile/metre and using the evidence before your eyes to delve into the inner workings of chemical processes in another matter. It requires both teacher and students to work with very tiny particles which you cannot see. However, you can see the effects they are having during chemical reactions. Letting the particles work for you though microchemistry techniques can be far more rewarding than just a "magical "event. I can still remember being excited (and I was in my 60s at the time ―sad, I know) in seeing the first alkali/acid halo.
Here is parade of halos for you.

The effect works because gases evaporate from solution (ammonia) or are evolved via a chemical reaction (sulfur, nitrogen or carbon dioxide). The gas particles (molecules) move through all the oxygen and nitrogen molecules in air within the Petri dish and finally enter the puddle.


Diffusion of gas molecules
We need have to get this into perspective. The molecules at 1atm and 300K are moving on average at speeds of 500metres per second (over 1100 miles per hour). There will be 1,000,000,000 to 10,000,000,000 collisions per second.
Stop a moment and let those figures sink in. That velocity is as fast as a bullet from a rifle, double the speed of an airliner). It would take you between 30 and 300 years to count that number of collisions at the rate of one a second.
The first diagram below represents ammonia diffusing; the first is a simplistic view of brown ammonia molecules diffusing from the container of ammonia solution to the puddle; this is typical of what you might find in a text book. The second diagram puts in 80 nitrogen molecules and 20 oxygen molecules. However this not a true reflection of the situation. I would have to draw 100 versions of the third diagram to ensure that an ammonia molecule is present as shown in the last diagram.
Stop a moment and let those figures sink in.
As well as the invisibility of the particles to our eyes, the students and teachers are dealing with enormous numbers of molecules of oxygen and nitrogen that the ammonia has to diffuse through.

Ammonia reaches the puddle of water
The ammonia molecules have been buffeted by air molecules and moved to the out parts of the puddle where they encounter water molecules. The NH₃ molecules become incorporated because there is intermolecular attraction between a water and ammonia molecules (see diagram on the right). This is electrostatic attraction. It arises because the molecular array has reduced its potential energy via this attraction. We give all sorts of names to these electrostatic attractions but they exist between particles from the structure to the atom to the extremely week induced dipole effects between inert gas molecules.

So how do the numbers add up here? You can detect the odour of ammonia at 1 ppm, that is, one part in a million. The picture on the left below shows one green ammonia molecule with 1000 molecules of water. I would have had to draw 1000 versions of the diagram below right to find that diagram on the left with the "green" ammonia molecule.
Stop a moment and let those figures sink in. ​
Ammonia in water is quite lonely. Many of our diagrams in textbooks give the wrong impression.

Ammonia is alkaline in water
Ammonia in water is weakly alkaline because not all molecules react with water to form ammonium and hydroxide ions. However, I am interested in the hydroxide ions because they are the ions that will ultimately react with the indicator molecule and change the colour on the outer reached on the puddle. On average, there is one hydroxide ion for every 240 ammonia molecules entering the water.
So, I would have to draw the water diagram 240 000 times to find 240 molecules of ammonia in which ONE will have dissociated ammonium and hydroxide ions
Stop a moment and let those figures sink in. ​
The presence of ammonium and hydroxide ions are even more remote. I admit I have not addressed the dynamic nature of this relationship between water and ammonia.

 Hydrochloric acid is a strong acid in solution
The puddle consist of 1 drop of water, one drop of Universal Indicator and 1 drop of 0.1M hydrochloric acid. The acid is effectively 0.03M. The diagrams below each contain 1000 molecules of water and that is about the right number (1800) to surround one yellow chloride ion and black hydrogen (or hydronium ion) which are both found on the left hand side.
Stop a moment and let those figures sink in. ​

 The Movement of Ions in Water
The majority of positive and negative ions, with their closely associated water molecules, which surround (solvate) the ion, move through water molecules, rather like the way you exit a football match.  Here are measured values (μ/10⁻⁸m²s⁻¹V⁻¹)

But for the hydroxide and hydrogen ions the rate is 20.6 and 36.2 μ/10⁻⁸m²s⁻¹V⁻¹ respectively. This is much quicker than expected. These tow ions do not diffuse but move via transport precesses.

The Movement of Hydroxide Ions in Water
As the OH- shunts to a water molecule that water molecule ejects another hydroxide ion and so on.  The negative charge is moving though the solvent water molecules, not the hydroxide ion itself. You can see this on https://gph.is/g/ZrPj8jE. Again this is far more involved than what you see here.I am limited by time and just the sheer complxity of making computer models.

The Movement of Hydogen Ions in Water
The hydrogen ion is a proton and there is evidence of clusters of water molecules with them. The simplest cluster (H₃O⁺) is shown between the square brackets. If a water molecule has enough energy to hit a cluster in the right position, it forms a cluster itself and the positive charge moves though the solvent water molecules. Effectively it is "hole" that is moving through the water.
The Reaction

The billions of particles in puddle are in constant movement and colliding. At some point, the hydroxide negative ion with its extra electron will encounter "a hole" and the charge neutralised. There is a sudden drop in potential energy manifested in the heat of reaction which increases the temperature of the puddle and some of it is distributed amongst all the micro-energy states of water (movement, rotation and vibration). This is an increase in entropy.

The approximate relative number of particles in the puddle can be seen on the left. You see just how "lonely" many of our chemicals are in our watery solutions.
Much of the research education is dealing with how we understand the nature and interactions of particles in chemical reactions. This is because equations in examinations rely on this understanding. And if you get the equations right, more marks are obtained in examinations.

So not only does the school student (and teacher) have to imagine in the view of chemistry, particles so small they cannot be individually weighed or seen directly, the student (and teacher) also have to cope with phenomenally large numbers. It is said there are 1,000,000,000,000,000,000,000 stars in the observable universe (1 x 10²¹) but in 18 ml of water there are 6 x 10²³ molecules. This uber-macroscopic number of interacting particles is as much an issue with the understanding of chemistry as the sub-microscopic nature of the particles. This needs a HUGE imagination!

Visualising particles in aqueuos solutions via computer is also is very difficult.
The nearest I have come to is Roy Tasker's work on http://www.visichem.thelearningfederation.edu.au/topic09.html.

Mounting the barrier of understanding between the macro event in a chemistry event and the interpretation at the nano level is one the most difficult achievements for both the student and the teacher..

Where does the chemistry teacher start with chemistry? The typical traditional start in  UK schools was with the destructive nature of the Bunsen burner with safety to introduce practical work and then onto elements, mixtures and compounds (which is quite a difficult concept) with separation techniques.

Chemistry is holistic with each concept affecting another. Quite honestly, you can start anywhere but there is that  understanding barrier in the way. Perhaps, like Alex Johnstone in 1966, and Peter Atkins with his 9 “big ideas” you should start as early as possible with the idea that matter is made up of very small particles and what you see at the macro level is a consequence of what is happening at the nano-level. These particles are too small to see directly so you have to use your thoughts, dreams, diagrams  etc to concoct visions of what is happening. I see many books/courses which start with "small particles" but the idea is not maintained through the ensuing pages. Both of Johnstone's text books (Chemistry Takes Shape Vol 1-5 in in1966 and Chemistry Takes Shape in 1980) maintained this commitment to the first big idea of Peter Atkins all the way through. Once a teacher starts with this difficult concept, reinforcement of the idea must be maintained. if you wish to read more about big idas see the article by Vincent Talanquer.· .

One year in 1980s, I was given £200 to my department by a satisfied parent. I could have taken the staff out to a local restaurant but instead, I bought a class set of Molymod® models (http://www.molymod.com/). Finding that the students just want to construct a dog or just connect anything to anything (that is fun, but not chemistry), I had to restrict the handing out to a few atoms and bonds at a time in deep sided trays. (But I still got questions like "Does this one exist, Sir? Sometimes there was quite a good aside, eg cyclopropane!!!)

On my visit to the ICCE2018 meeting I came across the superb VISCHEM computer models (http://vischem.com.au/) produced by the Roy Tasker group. Two videos caught my eye immediately because they are a part of my microscale workshops. The precipitation video (http://www.scootle.edu.au/ec/pin/HVFJXB?userid=71715 and scroll to "precipitation of an ionic salt") showed the silver chloride precipitate forming a line (picture below) and I thought that is just like one of my diffusing precipitate videos.












The Vis-Chem video of the macro event at the beginning of the video shows the  traditional test tube reaction. The colourless solutions have been already prepared and then mixed with a white precipitate forming.
Now watch the microscale version. Here is the line of silver and chloride ions coming together to form a precipitate. This microscale version though shows the addition of the solids to the puddle and  in the space of just over a minute, the whole macro process that the Vis-Chem video describes (and more because this procedure shows the dissolving process) takes place in front of the student in under 2 minutes.

The microscale puddle video shows what happens when silver nitrate and sodium chloride particles are dissolved in water how the ions are solvated by water (see below), breaking up the solid crystal lattice, how the ions move by diffusion using kinetic energy, and ultimately, how the silver chloride forms as a solid.

The second video concerned the displacement reaction between silver nitrate and copper metal (http://www.scootle.edu.au/ec/pin/HVFJXB?userid=71715 and scroll to Redox reactions). The macro experiment in the film shows the action of a colourless solution to copper foil. Silver is formed on the copper and drops off.

Now look at the microscale version under a USB microscope. The silver crystals (like fir trees) can be seen growing outwards.

We are witnessing evidence for the movement of electrons within metals. Why is this important? Because the mechanism happens in other situations

• All displacement reactions, where a more reactive metal displaces a less active metal ion from the  solution.

The rusting process where there are positive and negative sites on the surface of the metal and rusting accelerated by copper (see photo right) and slowed with zinc and magnesium. You can see more here and scroll down
Aishling Flaherty of Limerick University presented a plenary address on 1st year University students find "curly arrow" explanation of organic chemistry reactions difficult. ‘Twas ever thus. I did it in 1964 and it was tricky to many then. But chemistry then was taught as physical, organic and inorganic with distinct rivalries. Is it still?
Unless the Big Idea of electron movement (with electrons falling into a hole or even a depression “a partial hole”) is used in both inorganic and organic chemistry, we shall still be struggling with the understanding of these concepts. VisChem also looks at some simple organic reactions.
When the questions are asked how and why does this happen, then the Big Ideas of entropy increase and conservation of energy come into being, with the proviso that there may be a kinetic barrier. The molecular shape and intermolecular forces between molecules, especially in water at school level, are crucial in the mechanisms in which electron pairs are attracted to electron deficient (holes) species. There is periodicity because I can carry out these reactions with compounds of elements in the same groups. And it all happens because matter is made up of very tiny particles. It is all very holistic.
Appendix
Looking for connections in inorganic chemistry reactions and indeed, between different branches of chemistry, is a form of “chunking”, a process (see diagram below) in which “individual pieces of information are bound together into a meaningful whole” (Wikipedia). Instead of learning loads of separate facts, you apply basic ideas from which you can ascertain an answer to an exam question. Would it were so simple!
Exams are so important that students are scared of being wrong and teachers are worried for their jobs because they may be blamed for exam failures. It is safer to students to have many “fact cards” to learn by heart.
Application of present knowledge to new situations really throws students, A recent UK examination question about boiled carrots caused consternation because “we had not studied carrots” but they had studied osmosis in potatoes! And osmosis all about matter consisting of very tiny particles, invisible to the naked eye, the first of P W Atkins big ideas.