Question

a cake rises as it bakes because a chemical change causes ________to be produced

Answer 1

The answer i previously posted was dead wrong. Disregard it,
Here is a simple and easily comprehendable answer: http://www.thenakedscientists.com/HTML/content/latest-questions/question/1552/

Answer 2

For some reason I thought it had something to do with yeast ...*shrugs* thanks for the answer, @exuras

Answer 3

@kma230 That was my first conclussion and henceforth my first answer, so i did the exact same mistake.

Answer 4

Carbon dioxide gas bubbles produced by leavening agents such as yeast or baking powder causes a cake to rise.