Anoushka, New Zealand asked:
What makes a cake rise?
When making a cake you use baking powder or bicarbonate of soda, (or use self-raising flour, which already contains baking powder). Bicarbonate of soda contains carbon dioxide, which can be released as a gas by reacting it with acid or by heating. As the carbon dioxide is much bigger as a gas than it was in the bicarbonate of soda, it expands, makes bubbles in the cake mix and so makes the cake rise.