This was published in Education in Chemistry in March 2010 http://www.rsc.org/Education/EiC/issues/2010Mar/Endpoint.asp)
Friends of mine who teach biology, economics, or history have often expressed envy at the wonderful toys we chemists have to play with. How easy it must be, they say, to excite others about chemistry, to bring it alive in front of an audience, and to be able to provoke gasps of surprise and astonishment.
I saw my first demo lecture when I was 18 and was instantly hooked. I can remember it as if it were yesterday – it was Jearl Walker, the American physicist who for many years edited the Amateur Scientist column of Scientific American. He “drank” liquid nitrogen. He placed a finger in molten lead. And then he walked across a tray of hot coals. That apparent paradox we know as the Leidenfrost effect would be forever imprinted in my mind.
Since that day I have seen scores of demo lectures by lecturers of all ages and nationalities. Each time I have felt that same tingle before the start. It is chemistry in the flesh – matter being transformed before one’s eyes. The demonstrator is on a tightrope much like a circus acrobat, or an opera singer reaching for that high C. And the audience knows – perhaps secretly hopes – that things could go wrong. Indeed, Prof David Phillips of Imperial once said to me that it was important to have at least one failure in every lecture. Why? Because that way the audience would know it wasn’t television.
Seeing a classic demo performed – bubbles floating on a lake of CO2, a luminescent oscillator, the colours of a chiral material between polaroids, delayed hydrogen bangs – is like hearing a favourite aria or soliloquy. This is the stuff that brings chemistry alive, that brings home the reality, the concreteness of the profound abstractions that we take for granted. And no video, no recording, no animation can ever match the astonishing dynamic range of the phenomena one can show – smells, sounds, tastes, thumps, and flashes. Where else would one get such sensory stimulation?
And yet…… How is that many lectures, including my own, have left a faint sense of unease? For all the drama, the sturm und drang, the chemical histrionics, the laughter, the screaming, these shows sometimes left me wanting more. There seemed something missing. I just couldn’t put my finger on it. It was after giving a lecture that I’d archly named “Odeurs et Lumieres” – the title a homage to the great John Salthouse – that an elderly colleague of mine came up to me and told me how much he had enjoyed it. But then he added “But there wasn’t much of a theme”. I was crushed.
But as I thought about it I realized that he had unwittingly uncovered the key to my disquiet. There was no theme. Like so many other lectures I had given or seen before, I had chosen a title that was nothing more than an opportunity to throw together a number of chemical spectaculars, to wow the audience with some astonishing chemical tricks, guaranteed to give a result. And as I thought about it further, I asked myself what was the point? Was I just providing edutainment? Was this nothing more than chemical porn? I began to think about the titles of demo lectures I’d given or seen. The titles were often generic. “The Joy of Chemistry”, “Flash, Crackle and Pop”, “Kaboom” “The Elements” – you know the kind. They presented a series of demos, each explained in a superficial way, the chemical equivalent of those videos “Great Goals from the World Cup”.
Can it be that in spite of the incredibly panoply of phenomena we can show off, that we chemists still come across much like the proverbial alchemists of old – flashy showmen in white coats. Are we, through the talks that we give, sometimes failing to expose the difficult intellectual sinews of our subject?
I believe that we need to tell bigger, more ambitious illustrated stories that tie basic chemistry with big real world issues. We should be telling extended tales about how simple chemistry and chemical kinetics underpin pattern formation in the world around us, from the spots on leopards to the stripes on bees. We need to show trace gases in the atmosphere really can have an impact in our lives much as William Tyndall did in the 1860’s, shining infrared light through a lens made of ice and setting fire to a sheet of paper. And then using CO2 to block it. We need to tell the stories of ceramics from the earliest pots and tiles, to the magical whiter than white titanium dioxide that can be used to harvest solar energy. In doing so we will finally use the fantastic toys that we have at our disposal as a means to draw audiences into the thought processes of chemistry we will take them deep into our subject and really show just how profoundly chemistry is woven into the fabric of our lives and culture. Only then, perhaps, will we be able to shed that perjorative suffix that blights the proud name of Chem-ist.