In a previous post I wrote about my philosophy for teaching nature study to elementary-school kids, and promised to mention the book I'm going to use next year with Oscar. Here it is: Messing Around with Baking Chemistry by Bernie Zubrowski, from the Children's Museum Activity Book series. (Little, Brown, and Co., 1981; ISBN 0-316-98878-2)
Question: What makes things fizzy?
In this experiment, you will produce different combinations of mixtures that react to form fizzy solutions. You'll start with a baking soda/vinegar mixture and then move on to produce your own safe-to-drink, though not particularly tasty, lemon soda.
Science concept: Certain materials, when brought into contact with other materials, react in a way that forms bubbles. Acids and bases often combine to form carbon dioxide, which, as a gas, is what makes carbonated soda fizzy. You'll be experimenting with several common ingredients to determine which react in this way.