I have been asked to make a stage presentation on chemistry at my daughter’s elementary school for the school’s annual science fair. Fortunately, I am not shy on stage, so that is not much of an issue, but I have no experience making a show of chemistry publicly. The PTSA President-elect, who happens to be a good friend, suggested I make a large volume of hydrogen and blow it up. That is all well and good. However, I am open to suggestions for possible demonstrations. There will likely be several hundred parents and children, so some interactivity would be fun.

I considered filling balloons with oxygen and hydrogen, enough to represent giant model atoms in the shape of a water molecule, then using a giant model of a 9v battery to separate the atomic bond.

I also am thinking about building a primitive fire-extinguisher from a 2L cola bottle, water, vinegar and sodium bicarbonate. Like a large version of the experiment in the Golden Book of Chemistry Experiments. The point being chemistry is used to make useful things.

Overall, I want to impart that science and chemistry, is fun, practical and good for society.

Suggestions welcome!