Question: can you use baking powder and baking soda?
Answer: If you have a baking recipe that calls for baking soda, and you only have baking powder, you may be able to substitute, but you will need 2 or 3 times as much baking powder for the same amount of baking soda to get the same amount of leavening power, and you may end up with something that's a little bitter tasting, ...