California > New York (actually, idk, I'm just saying that to progress the thread).
@Schilcote:
Baking Powder = Baking Soda + solid powdered acid. To make baking soda bubble, you have to add liquid acid (vinegar, lemon juice, etc), but to make baking powder bubble, you just need to add water (as it dissolves the solid acid and become acidic itself).