Acid or no acid, that is the question

Baking soda or baking powder?  What's the difference??  Surely more than the color and shape of the box. 

Here's what I found out:

• Pure sodium bicarbonate
• Used as a leveling ingredient agent.  When it is mixed with a liquid and an acidic ingredient, the chemical reaction magic begins to happen. The result of this magic produces an expansion of  bubbles of carbon dioxide that expand under oven temperature, causing baked goods to rise.
• Acidic ingredients include, vinegar, lemon juice, buttermilk, sour cream, chocolate, and honey
• The chemical reaction begins to work immediately upon mixing, so get that dessert in the oven quick or it won't rise properly.
• Has a bitter taste unless countered with a the acid of another acidic ingredient.
• Commonly found in cookie recipes.

• Contains sodium bicarbonate, but also has an acidic ingredient (cream of tarter) and also a drying agent (usually starch.)
• Single acting baking powder is activated by moisture, so the recipe must be cooked soon after mixing.
• Double acting baking powder react in two phases, so can stand for a bit before baking.
• Often used in cakes and breads.

Substitutes:

• You can substitute baking powder for baking soda (you will need 3parts baking powder for every 1part soda, but it more than likely will affect the taste) but you cannot substitute baking soda for baking powder.
• Make your own baking powder: for every tsp of baking powder = mix 1/4tso baking soda, 1/2tsp cream of tarter, and 1/4tsp cornstarch.
• Recipes that call for both baking soda and powder, will also have the acidic ingredient to get the baking soda rockin'

Interesting Facts:

• Once you add enough Baking Soda to neutralize the acid of a batter, any extra that is added will work to aid in browning.  This is why a cookie recipe will call for baking soda when there is no acidic ingredient.
• Has your baking soda and powder been in your cabinet a bit too long?  Because they rely on a chemical reaction to work and chemical break down over time, heres a way to test them and make sure they haven't lost their mojo:
• Baking soda: 1/4t + 2t white vinegar should cause immediate foaming
• Baking powder: 1t + 1/2c of hot water should cause immediate foaming
• If they don't get all foamy like, replace those puppies!