The following video shows how yeast and sugar will produce carbon dioxide gas that makes the dough rise. The pink bowl contains yeast and sugar, the purple bowl contains just yeast and the green bowl contains just sugar.
Questions to think about:
- Why does the dough rise in the purple bowl?
- Why is there no rise in the green bowl?
- What is the name of the process by which carbon dioxide gas is produced?
- Can you write this process out as a word equation?
Mrs Tagore's Science Page 