Re: Is baking bread, cakes, or pancakes a physical or chemical change?

There is definitely a chemical change taking place during baking, and that is the conversion of baking soda (sodium bicarbonate, NaHCO₃) to carbon dioxide (CO₂). This is what causes the cake to rise, as the carbon dioxide bubbles get trapped within the cake.

I can also see your point about a physical change, as the cake mix goes from being a gooey liquid to being solid. The cake mix is a mixture of all your ingredients (flour, egg, cocoa, sugar etc) in water. As the cake is baked, the water evaporates. The evaporation is a physical change.

So, in conclusion, you were right. The baking of a cake/bread/pancakes involves both physical AND chemical changes.

Jonathan Feldman
University of Technology, Sydney
dr_chemistry@mad.scientist.com