|MadSci Network: Chemistry|
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.
University of Technology, Sydney
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