Twitter drew my attention this afternoon to a series of videos produced by the Royal Society designed to give teachers in schools some additional resources to encourage their pupils to do science experiments. They star the ubiquitous Professor Brian Cox, and they cover a wide range of science. You can see the whole playlist on Youtube here (although it is unfortunately back-to-front):
Although I ended up doing primarily theoretical work in my scientific career, there’s no question that ‘hands-on’ experiments played a big part in the development of my understanding of, especially, physics and chemistry. I remember vividly when I was about 12 years old doing a simple series of experiments in which we weighed out samples of chemical material of various types, then burned it somehow (usually over a bunsen burner) and weighed what was left. Commonsense based on experience with burning stuff like wood and paper is that the process reduces the amount of material so I expected the mass remaining at the end to be less than the initial mass. The first stuff that I did was a few grains of calcium. I couldn’t believe it when the residue turned out to weigh more than the stuff I started with. I was sure I was wrong and got quite upset for failing such an elementary practical exercise, but the same thing happened every time whatever the material.
Of course, the explanation is that the process going on was oxidation, and the calcium was actually combining with oxygen from the air to form an oxide. It did look as if some kind of destruction had happened, but the oxygen taken from the atmosphere had bonded to the calcium atoms and this increased the mass of the residue.
The teacher could have talked about this and explained it, but it wouldn’t have had anything like the impact on my understanding of discovering it for myself.
That’s a personal story of course, but I think it’s probably a widespread educational experience. These days few students seem to have the chance to do their own experience, either because of shortage of facilities or the dreaded ‘Health and Safety’ so I think any effort to encourage more teachers to allow their students to do more experiments is thoroughly worthwhile!Follow @telescoper