The Year of Revolution

Classic Kit has turned into something of an obsession – this is shown by the fact that this month is the 75th column in the series. Looking back at the early ones, I wish I could rewrite them and correct some of the omissions. This month gives me the opportunity to do just that as I finally decided to write about Robert Kirchoff and his spectroscope. It’s an opportunity to do slightly more justice to Robert Bunsen, whom I rather demeaned when I wrote, rather lazily in retrospect, about the Bunsen burner.

What I failed to do was to draw proper attention to Bunsen’s incredible contributions to chemistry, from his battery to his role in the development of spectroscopy and in the characterization of the rare earth elements (which you can find in my Terra Rara lecture from the Royal Institution).

[Picture of a prism spectroscope]

The “old fashioned” spectroscope that our undergraduates use in the physical chemistry laboratory. The cover over the prism has been removed to show it in its full glory.

We have an old but solid spectroscope in our teaching lab – slit, prism, collimator lens etc that our students use. Although some look at it and think “relic” and ask why on earth we use something so old fashioned, the point is that it’s not a black box, unlike a typical UV/Vis spectrometer. You can see all the bits and follow the path of the light as it travels through the device and you get to actually see for yourself that the sodium D line is a doublet.

The device was not completely Kirchoff’s, of course, similar devices had been built before him. I’ve had to condense that part of the story down to just a list of names. But what is important is that it was Kirchoff, with the aid of Bunsen, who joined the dots and realized the true importance and utility of the device. In doing so, the two of them changed our world.

I give you Kirchoff’s spectroscope.

[I should mention that we also have an undergraduate experiment in which students construct a spectroscope from a cardboard box and a diffraction grating, using a helium spectrum to calibrate their scale and then use the device to measure Ryderberg’s constant for hydrogen. It’s a lovely, simple experiment and again it’s a way of deconstructing scientific ideas by getting students to use almost improvised methods.]

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Anschütz’s manometer

Several years ago Alfred Bader, the founder of the Aldrich Chemical Company, who is also known for his interest in Dutch painting introduced me to the name of Richard Anschütz, a late 19th century organic chemist who was August Kékulé’s protégé and eventually succeeded him as Professor of Chemistry in Bonn.

Bader, then well into his 1970’s would visit chemistry departments and gave talks about the untold story of four coordinate carbon and the structure of benzene. The villain in the story was Kékulé, by all accounts an insecure egomaniac who may, perhaps, have got some of his best ideas from others. Bader’s disdain for Kekulé was palpable and infectious.

A hero in the tale was Richard Anschütz who spent many years trying to piece together the stories of Archibald Scott Couper and Johann Josef Loschmidt. Anschütz gathered much of the evidence that they had both preceded Kékulé in their proposals, but never got the credit they deserved.

So this month’s Classic Kit is a tribute both to Anschütz – whose little book “Die Destillation unter vermindertem Druck in Laboratorium” I have drawn on previously (see Claisen’s Flask and Perkin’s Triangle) – and to Alfred Bader, a great benefactor of British chemistry teaching. He is now too elderly and frail to travel any more, and who will probably never read this. He is widely remembered across the UK.

Anyway, here is Anschütz’s manometer. If you’re a chemist, you’ve used it.

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Cheltenham Science Festival 2013 – Programme now out

The programme for Cheltenham SciFest is out at last and it looks absolutely fantastic with, as usual, a mix of provocative, wacky, thought-provoking, and downright silly events to tickle the minds of old and young.

Check out the “What’s On List” for the events which you can start booking from 22 April (unless you’re a member in which case you already know about it). In addition the BBC will bringing their own parallel sessions to their own tent – we won’t know their programme for a while yet.

Why should you visit the CSF? Because I think it’s the Ngorongoro Crater of science festivals: although the terrain is very varied, the action is all focused in a relatively small area, so you don’t have to cross town to go from one thing to another. And the relaxed atmosphere means you have a good chance of seeing, if not chatting with one of the Big Five if you hang around in the Gardens in the afternoon.

C’mon down.

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Strange Ice

My long-delayed new talk “Strange Ice” is coming up next week.

Though you will find it in every refrigerator in the world, ice is a materials so strange that it breaks almost every rule in our textbooks. Yet its very familiarity makes us take it and its properties completely for granted. The centenary of X-ray diffraction, gives the opportunity to take stock of its properties, how it compares with other ices, and the way in which water ice may be the canary that warns of a future much less certain than we imagine.

The lecture is free and open to the public under the auspices of our Department’s Chemical and Physical Society. It’ll be in the UCL Chemistry Auditorium, WC1H 0AJ. If you can’t make it there are other opportunities to see it again in Cambridge, London, Edinburgh and Cheltenham in the coming months.

[Poster for Strange Ice]

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Fleur de Geek

People are starting to notice the rather ludicrous shirts some of us are wearing. I blame Mark Mio and Jim Al-Khalili for this. What really amused me last summer was to go to a big family lunch in Italy and to have series of relatives come up to me, stare and my shirt and then say “Che British”. High praise indeed. Anyway, there’s a nice comment on this trend over at Julie Gould’s blog about what I’ve called Fleur de Geek.

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Are the gloves coming off?

It’s now about almost three weeks since I started asking questions about gloves (if you haven’t seen the other posts they are here and here). Departmental policy, with approval from the UCL Safety Office, is that gloves should only be worn if there is a recognized need, to be determined on a case-by-case basis and that the routine wearing of gloves is to be discouraged.

So I went into our teaching labs today to see what was going on and to talk to the students. Slightly to my surprise, multiple boxes of disposable gloves had been issued, and perhaps as a result, over half of the students in the lab were wearing them. Here are two photographs of students who were making organic-soluble nickel complexes.

The hands of two undergraduates half way through a lab class in our Department. The question I put to them was: “Would your hands have this much stuff on them if you weren’t wearing gloves?”

 

 

I talked to them, and each one suggested that they probably wouldn’t have spilled as much had they been not been wearing gloves.  I also noticed that half of the students I spoke to (three out of six) used their gloves to adjust their hair while we talked. Another wiped his faces on the sleeve of his lab coat. None of them were aware of it until I pointed it out to them.

You might argue that this is a training issue and that we should spend more time spotting when students have dirty gloves and when they scratch or run their gloves through their hair. I would argue that these students need to take more responsibility for their own safety.

We have now received several hundred pairs of reusable Anson Sol-Vex nitrile gloves (shop around as prices vary wildly). For some reason they haven’t been issued to students in our teaching labs. We’ll see what happens over the next few days.

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More on gloves in the lab

[A picture of children doing experiments in the lab]

Children mixing citric acid and bicarbonate at a Salters Festival in a few years ago. Do the children need to be wearing gloves in this situation?

A few days I wrote about my worries about students wearing disposable gloves in the lab. I started discussing it with colleagues in the department, including several who sit on our safety committee. One of the comments that came out of these discussions was the number of incidents we’ve had over the past few years involving students transferring chemicals from their gloves to their face, neck, and elsewhere. In fact, if you stand and watch students in the lab – as I had occasion to this week – you see them contantly adjusting their safety specs and scratching their neck, nose, ears at regular intervals. All wearing gloves, of course. And because they are wearing the gloves, they are blissfully unaware that there might be anything on the outside of the glove.

The students, secondary school students,  who were dissolving zinc in quite dilute HCl were, of course all wearing disposable gloves. It’s true that they had to boil the solution to driness, but it’s hard to imagine anyone getting hurt doing that, especially as the procedure was carried out in a fumehood. Nevertheless they were instructed to wear gloves in addition to safety glasses and lab coat. I stood around and watched. The students didn’t have much to do while the solutions boiled and they stood and chatted. Their hands went up and down, touching, fiddling with mobile phones, onto benches and, inevitably, onto their faces.

When I question them, the students  were horrified at the suggestion that maybe they should take their gloves off. Until, that is, we talked about it, and during the coversation I’d drawn attention to the fact that each one of them had touched their chin, cheeks, neck etc. with the gloves. Not to mention their phones, their pens, their notebooks.

But in a way, with an aqueous solution, you know that the gloves are an actual barrier. But we don’t do that much aqueous chemistry. We use solvents. You should try this a simple experiment: squirt some solvents – acetone or dichloromethane, say – into some nitrile or latex gloves and then wait to see how you soon you could smell the solvent. When I did it last week, the answer was “instantly”. In other words the gloves (and you only have to do is look up the manufacturers’ specifications to see that this is the case) provide no protection at all. Indeed what they do is trap the solvent between the glove and you, giving your fingers a little more quality time to interact. Your hands being damp, you aren’t even aware that it’s happening.

In the labs our students get solvents on their gloves all the time, especially when washing up.  It’s clearly nonsense. By providing gloves we are actually lulling our students into a false sense of security. They get stuff on their gloves and even if they’re aware of it, they just assume that because they have gloves on “it’s OK”. Risk compensation works in mysterious ways.

It’s very different if you don’t wear gloves. Today a colleague and I spent some time electrolyzing first molten potassium hydroxide (KOH), and then potassium carbonate at red heat (if you’re interested, it’s something to do with Brian “Delia” Cox). The spray from the bubbles generated in the electrolysis was intense and after a while everything was coated in a thick layer of KOH. We fiddled a little with the electrodes knowing full well that we had some ferociously caustic material a few centimeters from our hands.  And while doing so, I got some KOH on my skin. It stings. It feels soapy. But the sink is there, right behind you. You rinse. It’s sorted.

Now I’m not saying that one shouldn’t wear gloves under any circumstance. Far from it. Clearly there are issues of scale and of context. But what I am saying is that for the vast majority of procedures like the ones we conduct in our teaching labs, gloves may look smart but they have precisely the opposite effect to what we intend.

It’s wrong, it’s wasteful, and it’s expensive. And we have plenty of, for the most part, fairly minor incidents to deal with that probably would not happen if our students didn’t wear them.

So the plan is to go even further and actively discourage students from wearing gloves as a matter of routine in our labs. Why? Because, completely contrary to “common sense”, we believe they’ll be safer and actually work better in the lab.

Will it catch on? I wonder. It’s not going to be easy.

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