Bob Worley (ably assisted by Emma, Magda and Kay) has been organising a semi-regular get together of those interested in practical work over the last few years. There is a good mix of teacher/lecturers/technicians and others to make the conversations fruitful and wide ranging. Sadly I missed the Tuesday afternoon session (and the meal…) but Wednesday was jam packed.
Kay Stephenson lead off with a brief summary of the issues with nickel chemistry, and the importance of reading the documents CLEAPSS have available on this. While the general guidance is against using nickel salts, special risk assessments are available once you’ve had a conversation with an adviser, and low concentration solutions in small volume pose low risks. We carried out a simple ligand exchange practical that takes only a couple of minutes to carry out, but opens up many avenues of discussion.
Nickel salts reacting with 1,2-diaminoethane is different proportions.
Catherine Witter (AQA) and Andy Brunning (OCR) then gave presentations on the current state of practical endorsement at A level and the first series of the new GCSE sciences. It was good to hear that the vast majority of students are achieving the practical endorsement, confirming again that this style of assessment is helping to raise the competence of a wide range of students in practical skills.
We then set up our iron(II)/silver(I) equilibriums to be assessed by thiocyanate titration later on. This is a microscale reaction, that allows you to get at the Kc relatively quickly and easily (especially if you code up the calculations in Excel). We used Bob’s version which is a gravimetric titration – a volumetric one is from RSC is here. I also did a quick Google on this – its a venerable reaction!
Niki Kaiser and I then had a double act on memory, cognitive load and practical work – my slides are here. Niki gave a well polished overview of the basic architecture of memory, including working and long term memory, and what it means to remember and learn. I then briefly summarised my ideas around integrated instructions and some of the data I have collected from my classes. The other delegates then had a chance to look through my AQA Required Practicals Integrated Instructions and provide some feedback. It was gratifying to get some positive feedback and ideas.
The afternoon kicked off with Matt Endean (deputy director of CLEAPSS) discussing some recent safety issues that have affected practical chemistry. The notorious affair of 2,4-DNP makes an interesting case study in how vital technicians are in our schools, and the unintended consequences of tight budgets and reduced technician time in schools. Thankfully bomb squads are no longer necessary, and specialist contractors are available should such as situation happen in the future. If in doubt – contact CLEAPSS!
Chris Lloyd from SSERC then talked us through practical work in Scotland. I must say, it does sound like quite a well throught through system – subject specialists only from third year onwards, a requirement for teachers to complete a certain amount of relevant CPD every year, funding for SSERC, students completing research projects which are externally marked. Quite a different regime.
John Baum from University of Lancaster then took us through some fascinating gold nanochemistry, including simple but brilliantly effective reactions of gold nano-particles with sodium chloride, melamine and partitioning effects. Red gold, blue gold, and gold gold were all observed!
Finally, a microscale tour-de-force from Bob and we got to be hands on. Simple dehydration of propan-2-ol on a microscale, making good use of three way valves and syringes. And the final wonder – the absolute joy from Bob of the hydrogenation of some just synthesised propene by passing the gases over palladium on carbon, with the resultant clear reduction in gas volume. Brilliant.
As always, CLEAPSS provided an excellent venue, and the day was a true reflection of what high quality CPD can be. I learnt plenty, and got to share some of my ideas with other people who were interested. If you get the chance in the future, I thoroughly recommend it.