Experimenting in a pandemic

If you think back to chemistry lessons at school, what do you remember most clearly? It will very often be practicals, experiments or demonstrations. My own favourite chemistry lesson was the first that I can remember: the famous demonstration of the reaction of alkali metals with water, and thence the Group 1 reactivity series. Even in the 1970s, no-one was mad enough to let a class of 11-year-olds loose with such reagents. It was demonstrated by the teacher –although not, as far as I can remember, from behind a plastic screen – and the resulting explosions and brightly coloured flames were a delight. This demo is still done in classrooms today, and if pupils want to know what happens to rubidium and caesium at the bottom of the periodic table, YouTube offers plenty of videos.

There is still a ‘wow’ factor in practical chemistry. Many secondary chemistry teachers report that their younger pupils, in particular, look forward to practical lessons enthusiastically, and suggest that chemistry without the practical element would be a rather dry, factual subject. And experiments, even when demonstrated, have a very useful pedagogical function. Many chemistry students will agree to this comment from a current year 9 student (13–14 years old): ‘[This distillation] was a teacher demo, but it was more interesting and easier to understand after we had seen it done.’